excursion guide

EXCURSIONSIGC 2020 DELHI

Geological Survey of IndiaMinistry of Mines

Government of IndiaIGC

DELHI 2020

Contents

1 Jammu and

Kashmir Ladakh 1b 4 Days 3 Nights 4

1c 4 Days 3 Nights 5

Glacial-Deglacial Archives, Ladakh 1d 4 Days 3 Nights 7

2 Himachal The Thrust Sequence of NW Himalaya 2a 4 Days 3 Nights 9

Intensified Monsoon phases in Satluj Valley 2c 4 Days 3 Nights 12

3 Uttarakhand Thrust Tectonics in Central Himalaya 3a 5 Days 4 Nights 14

3b 5 Days 4 Nights 15

Late Quaternary Aggradation –Degradation of Alaknanda River 3c 4 Days 3 Nights 17

4 Haryana Holocene Climate and Harappan Civilization 4 3 Days 2 Nights 19

5 Uttar Pradesh Geodiversity of Ganga Dispersal System 5 3 Days 2 Nights 21

6 Rajasthan Paleoproterozoic Lead-Zinc sulfide metallogenesis in

Aravalli-Delhi Orogenic Belt 6b 4 Days 3 Nights 24

6c 4 Days 3 Nights 25

Malani Volcanic Province- Hot Spot Triggered Felsic Volcanism 6d 4 Days 3 Nights 29

Thar Desert and its Evolution 6e 4 Days 3 Nights 31

6f 3 Days 2 Nights 31

7 Gujarat Stratigraphic Architecture of Rift to Passive Margin Evolution

in Kutch Basin

Surat - Diamond Cutting and Polishing Hub 7b 2 Days 1 Night 35

8 Madhya Archaean Craton and Mineralization 8a 4 Days 3 Nights 37

8b 3 Days 2 Nights 38

Sausar Mobile Belt of Central Indian Tectonic Zone 8c 4 Days 3 Nights 40

Precambrian Paleobiology - A Window for the Microbial Earth 8d 4 Days 3 Nights 42

Panna Diamond Belt- A Historical Diamond Mining Center 8e 4 Days 3 Nights 44

The Indus Suture Zone of the Himalayan Collision Belt, 1a 4 Days 3 Nights 3

Pradesh 2b 4 Days 3 Nights 10

6a 2 Days 1 Night 23

7a 4 Days 3 Nights 33

Pradesh

9 Maharashtra The Deccan Volcanic Province 9a 5 Days 4 Nights 46

The Western Ghats 9b 4 Days 3 Nights 50

Sr.

No. No.

State Excursion Theme Trip Plan Duration Page

No.

Excursion Destinations

2

Synoptic Geology

The Ladakh and Karakorum Terranes expose the rocks of north Indian Continental margin, the Indus and Shyok suture and the

southern part of the Eurasian plate. The Indus Suture marks the line of collision dated at early Eocene. To the south of the Indus

suture is the Tethyan Lower Mesozoic carbonates deposited in the Neotethyan shelf zone. To the west the Spongtang Ophiolite

represents the remains of the post collision obduction of the ophiolite on to the Indian shelf. Eclogite indicative of high-pressure

metamorphism in the suture zone are exposed in SE part of the area near Tso Morari.

The rocks of the Indus Suture Zone are represented by slope sediments of Lamayuru Formation containing Permian and

Triassic Olistoliths; thinly bedded flysch sediments of Nidam Formation; the late Jurassic to Cretaceous arc sequence of

volcanics and radiolarian chert of Dras Formation; the Shergol Ophiolite Complex in the NW and Nidar Ophiolite Complex in the

SE and post collisional intermontane continental deposit (Indus Formation and Kargil Formation). The northward drift of the

Indian plate resulted in development of the Ladakh volcanic arc with intrusion of voluminous Ladakh granodiorite (110 - 40 Ma)

and extrusion of Dras and Khardung volcanics preserved in the southern and northern margin of the arc.

The Ladakh Terrane is juxtaposed with the Karakorum Terrane along the Shyok Suture Zone comprising dismembered units of

ultramafics, gabbro, basalt and sediments including molasse. The Karakorum Terrane representing the southern margin of

Eurasia exposes the Karakorum Plutonic Complex and marble - metapelite - amphibolite rocks of the Pengong Metamorphic

Complex.

The Shyok Suture Zone is disrupted by the 700 km long NE - SW

trending Karakorum fault. The fault bifurcates at Sati and is

exposed as the northern Pangong and the southern Tangtse

strand. The Pangong Range has formed due to transpressive

dextral strike-slip movement along this fault with estimated

displacement ranging from 40 to 400 km.

The Pangong range exposes calc-silicate, migmatised diorite (107

to 82 Ma) and amphibolite intruded by 15 to 22 Ma two mica +

garnet monzogranite.

The Pengong Tso

1. Jammu & Kashmir:The Indus Suture Zone ofthe Himalayan Collision Belt, Ladakh

The Diskit Gompa

Overview

Ladakh, a mountainous cold desert in the state of Jammu and Kashmir, is situated at the western end of the

Tibetan Plateau. The present rugged topography with altitudes ranging from 3000 to 8000 m is the result of

upliftment of the entire region due to the collision of India with Eurasia and concomitant denudation by ice,

wind and rivers. The people of this region are hardy, high spirited and maintain their cultural traditions.

Ladakh is famous for numerous lakes, monasteries, palaces and some of the highest motorable passes in

the world.

IGC

DELHI 2020

3

Trip Plan No. 1a: 4 Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Vruins visit to Hemis Gompa, Semo Gompa, Shey,

Arrival Leh by air Thicksey, Sindhu Darshan, Spituk etc.

Shopping for souvenirs and curios at Leh

Day 2 Leh-Lamayuru- Study outcrops of Ladakh Granitoid Visit to Alchi Gompa, Lamayuru Gompa and Mulbek.

Mulbek-Kargil Complex, Indus Group and Sangeluma Rock carving of Maitreva Buddha at Mulbekh

Group including Dras Volcanic Formation.

Excellent palaeo-lake deposits at

Spituk and Lamayuru

Day 3 Kargil-Batalik- Study outcrops of Ladakh Granitoid Visit to Dah-Hanu settlements of Drokpa,

Hanuthang-Leh Complex, Indus Group and Dras Likir Gompa, Pathar Sahib Gurudwara

Volcanic Formation

Day 4 Departure Leh Arrival

New Delhi by air

Section Highlights Tourism Offered

View of Lamayuru Gompa Rock cut Buddha at Mulbek

4

Trip Plan No. 1b: 4 Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Visit to , Shey, Thicksey, Sindhu Darshan,

Spituk Hemis Gompa etc.

Sightseeing and shopping for souvenirs

and curios at Leh

Day 2 Leh-Chang La (pass) Study rocks of Ladakh Granitoid Complex

(LGC); dismembered ophiolite lenses at

Tsoltak; intermediate-basic volcanics and

sediments of Shyok Group;

Day 3 Darbuk-Pangong Tso High grade rocks of Pangong Metamorphic Visit to Pangong Tso (Lake Pangong)

Complex and Karakoram meta-sedimentaries

(Lukung Formation). Pillow basalt at Chusul


New Delhi by air

Arrival Leh by air

-Darbuk

-Chusul-Leh


Pengong Injection Complex near Tangtse.Marble – amphibolite – metapelite sequence, on way to Pengong Tso.

IGC

DELHI 2020

5

Trip Plan No. 1c: 4 Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Sightseeing and shopping for souvenirs

Arrival Leh by air

Day 2 Leh-Diskit Ladakh Granitoid Complex; Karakoram Khardung La one of the highest

metasediments and Karakoram Granitoids

Day 3 Diskit-Leh Acid-intermediate volcanics (Khardung Sightseeing along Nubra and Shyok

volcanics); recent river sand dunes at

Hunder

and curios at Leh. Visit to, Shey,

Thicksey, Sindhu Darshan, Spituk Hemis

Gompa etc

(Nubra valley) motorable roads in the world, sightseeing

along Nubra River, Panamik, Diskit

Gompa

Rivers; Hunder is known for Bactrian

camels


New Delhi by air


Bactrian camels of HunderSand dunes at Hunder

6

Synoptic Quaternary Geology

The Indus River System is climate sensitive and has experienced changes due to fluctuations in SouthAsian Monsoon. Loose to

semi-consolidated alluvial, glacial, fluvio-glacial, lacustrine and debris deposits are scattered in Indus, its tributaries and on the

mountain slopes. Quaternary sediments occur as terraces along

the Indus River, moraines in the main river valley and low order

drainages, alluvial fans at the confluence with main river, lake

deposits as patches on the banks of Indus River and debris

deposits on the hill slopes.At most of the places, two or more types

of deposits occur together in inter-layered and inter-fingered

pattern. Lateral, median and terminal moraines are preserved on

northern and southern slopes of Ladakh Range (along Leh-

Khargung-Khalsar road) at Darbuk, Chushul and Nyoma areas,

connected with roads.

1. Jammu & Kashmir:Glaciation - Deglaciation Archives, Ladakh

Terraces of Indus river near LehMoraine heaps near Baralacha la

Glacial carved valley near Leh

Shey Monastery, Leh

Overview

Jammu and Kashmir is one of the important tourist states of India in western Himalaya with scenic valleys,

glaciated peaks, meandering rivers and blue lakes. It comprises three regions namely Jammu, Kashmir and

Ladakh. Some of the lofty mountain ranges of the region include Pir Panjal, Zhankar, Ladakh and Karakoram.

Ladakh, also known as the roof of world, is a high altitude, cold - arid region with spectacular landscape

composed by glacial, alluvial and aeolian landforms. Bare valleys ornamented with moraines and glaciers

provide a unique architecture experience of natural beauty. The rock surfaces, bereft of vegetation, exhibit the

geological features like a textbook. The high mountain ranges have the highest motorable pass of the world

Khardung La - at 5870 m. The Indus River valley shows a parallel network of tributaries like Shyok, Nubra,

Tangste and Hanle, imparting pristine beauty to the landscape.

IGC

DELHI 2020

7

Trip Plan No. 1d: 4 Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Acclimatization and local tourism Leh Palace, Shey, Thicksey and Hemis

Day 2 Leh-Nimoo- Fluvial-glacial-deposits. Alluvial fans and Alchi Gompa, Lamayuru Gompa and

moraines, Lamayuru Lake deposit

Day 3 Leh-Khardung- Glacial morphology. Lateral and median Khardung la (Highest motarable road in

Karoo-Leh

Arrival Leh by air Gompa. Shanti Stupa

Lamayuru-Leh Mulbek temple

moraines in Leh-Khardung valleys. world (5400m)

Terraces of Indus


New Delhi by air


Lake deposit of Lamayuru is one of the best in the world. The laminated clay deposit is an example of

in a cold phase in the region. The Pangong Tso (Pangong Lake) is the largest saline lake of world whose

expansion and contraction during Holocene are exhibited as terraces, water marks and exposed lake floor sediments. The

bouldary fluvial terraces near Darbuk are one of the rare archives of a catastrophic glacial melting. The proposed excursion is

designed to show a comprehensive history of warm and cold periods in Ladakh region and their litho-geomorphic manifestations

.

>80 m thick bowl shaped

slow deposition

Patches of lacustrine clays

along Indus River.

Glacial melt lake deposits, Leh. Lateral moraines on Phyang Plain.

8

Snow clad peaks of Himachal Pradesh

Synoptic Geology

The E-W trending arcuate Himalayan Orogen is subdivided into four stratigraphic entities disposed parallel to its longitudinal

axis. From south to north the stratigraphic divisions are (1) The Paleogene and Neogene sequences, (2) the Proterozoic Lesser

Himalayan sequence, (3) the Proterozoic to Ordovician Greater Himalayan Crystalline Complex and (4) the Proterozoic to

Eocene Tethyan Himalayan sequences.

The oldest units of the Tethyan Himalayan sequence are the Proterozoic to Middle Cambrian sediments of the Haimanta Group

overlain by Lower Ordovician to Devonian shelf sequence along a plane of regional unconformity. The rocks range in age from

1840 to 40 Ma.

The Greater Himalayan Crystalline Complex (GHCC) bound between the Main Central Thrust (MCT) in the south and South

Tibetan Detachment (STD) in the north is represented by inversely metamorphosed high grade rocks with ages ranging from

?1800 to 13 Ma. The MCT in Himachal Pradesh defines broad zone of shearing involving the top levels of Lesser Himalayan

sequence and the lower levels of GHCC besides different thrust sheets within it such as Kulu Thrust, Jutogh Thrust and Vaikrita

Thrust. Towards the southeast the rocks of the Kulu Group,

are thrust over the Lesser Himalayan sequence. The Jutogh Thrust Sheet

(JTS) metamorphosed from biotite to sillimanite grade occurs as a klipp in the Shimla area and as a half-klippé in the Chour

area. The JTS rides over the rocks of the Kulu Group along the Jutogh

Thrust and is ridden over by the rocks of the Vaikrita Group along the

Vaikrita Thrust.

The Vaikrita Thrust Sheet (VTS) is characterized by granitic intrusives

of Lower Paleozoic age. The rocks of the Lesser Himalayan sequence

are exposed between the Main Boundary Thrust (MBT) and the Kulu

Thrust. Towards southeast the rocks of Shali Group are overlain by the

Shimla Group and the sedimentary sequences of Blani, Infra-Krol and

Krols. The rocks of Sundernagar Group are thrusted over the

Paleogene sequence and represented by Sirmur Group divisible into

shale, nummulitic limestone bearing Subathu Formation, red to purple

represented by calcareous rocks of the Shali Group and the

quartzite, volcanics and slates of Sundernagar Group,

é

2. Himachal Pradesh:The Thrust Sequence of NW Himalaya

Kinnaur apples

Overview

Himachal Pradesh, a state in northern India, is known for its natural beauty. The state is the third fast growing

economy in India. Almost the entire state is mountainous with elevations ranging from 300 to 7000 meters

above mean sea level. Major rivers flowing in the state include Chenab, Ravi, Beas, Sutlej and Yamuna.

Climate varies from hot sub-humid tropical in the south to Alpine and glacial in the north and cold desert in

areas like Lahaul and Spiti. The state is known for its handicraft which include shawls, carpets, wood work

and printing.

IGC

DELHI 2020

9


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Sight seeing at Shimla

Arrival Shimla by air

Day 2 Shimla-Rekong Pio Study of Greater Himalayan Sequences of Sight seeing at Rekong Pio

Shimla Klippe; rocks of Proterozoic Rampur

Group (quartzite and metavolcanics)

exposed in Kulu-Rampur-Larji window;

inverse metamorphic sequence of the

over-thrusted rocks

Day 3 Rekong Pio-Shimla Study of South Tibetan Detachment Surface

and the Lower Paleozoic Kinner-Kailash

granite

Day 4 Departure Shimla

Arrival New Delhi by air


shale and micaceous sandstone of Dagshai Formation, massive sandstone and grey to red shale dominated Kasauli Formation

along the MBT. The Paleogene sequence is thrust over the clastic fluvial sequence of Neogene Siwalik Group along the

Palampur Thrust.

Rotation of feldspar porphyroclasts inLower Palaeozoic Kinner Kailash granite

Sinistral sense of shear in the rocksof Central Crystallines, Rekong Pio

10


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure Delhi Sight seeing at Chandigarh and

Arrival Chandigarh

by air

Day 2 Chandigarh-Shimla Himalayan Frontal Fault at Panchkula; Sight seeing at Shimla

Nahan Thrust at Kalka; Main Boundary

Thrust between Kasauli and Blani/Krol

Formations at Anjhi; Chail Thrust

Day 3 Shimla-Kumarhatti- Study of Main Boundary Fault at Kumarhatti

Chandigarh

Day 4 Departure Chandigarh

Arrival Delhi by air

Pinjor Gardens

between Siwalik and Subathu;

Nahan Thrust at Nahan


Pinjor Gardens

IGC

DELHI 2020

11

Image of a part of Satluj valley


From its origin in arid zone, the Satluj River passes though humid zone between Karcham and Rampur, semi-arid zone between

Rampur and Luhree and again humid zone between Sundernagar and Ropar. Upstream of Rampur, the river has steep walled,

V-shaped narrow valley while in downstream it shows wide, meandering form.

Quaternary sediments of alluvial, fluvial, debris flow and lacustrine origins occur along the Satluj and its major tributaries in the

form of terraces, hill slope debris and alluvial fans. The river shows both degradational and aggradational habits. The excursion

will show the climatic sensitive sectors where >80 m thick pile of sedimentary deposits show variations in paleo-climatic

conditions.

2. Himachal Pradesh:Intensified Monsoon Phases in Satluj Valley

Satluj valley architecture near Nogli, Himachal Pradesh Fluvial deposit 200m

above river bed, Himachal Pradesh

Overview

Satluj, a perennial river of Indus System originates from Rakshas Tal and Mansarovar Lake in Tibet at an

elevation of 4572 m. After traversing about 320 km through the Higher, Lesser and Outer Himalayan belts In

Himachal Pradesh, it debouches on the alluvial plain near Ropar in Punjab. Spiti and Baspa Rivers are its

major tributaries.

12


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Delhi-Chandigarh- Siwalik sections near Kalka Pinjor gardens, Shimla

Shimla by rail/road

Day 2 Shimla-Rampur- Alluvial fans, debris and terrace deposits of Baspa Valley

Satluj along Rampur-Tapri-Karcham.

Lacustrine sequence near Sangla

Day 3 Rampur-Luhree- Gravelly and sandy terrace sections. Satluj Valley

Rampur

Day 4 Rampur-Chandigarh- Landscape along Shimla-Solan highway

Delhi by Road/Rail

Sangla-Rampur

Meandering and straight river morphology


Sandy terrace of Satluj near Dattnagar, Himachal PradeshGravelly terrace at Luhri, Himachal Pradesh

IGC

DELHI 2020

13

Bells toll at Chitai temple, near Almora.

Synoptic Geology

The foreland sediments of the IndoGangetic Plains are overthrust by the Neogene Siwalik Group of rocks along the Main Frontal

Thrust. The Siwalik Group is in turn overthrust by the Lesser Himalayan rocks along the Main Boundary Fault. In the outer zone

of the Lesser Himalaya, the Nagthat Formation is overlain by the synformally disposed Mussoorie Group comprising Blaini

Formation, Krol Formation and Tal Formation. Towards the inner zone of Lesser Himalaya the dominant unit is the Garhwal

Group which is subdivided into the granite-gneiss and mica-schist dominatedAgastmuni Formation; metavolcanic and quartzite

dominated Uttarkashi Formation; dolomite with minor phyllite and quartzite bearing Tejam Formation and quartzite-slate-

phyllite dominated Berinag Formation. The rocks of Garhwal Group are tectonically overlain by the rocks of Central Crystalline

Group along the Main Central Thrust (MCT). The MCT is defined by a broad zone constrained by Munsiari thrust (MCT 1) at the

bottom and Vaikrita thrust (MCT 2) at the top. The rocks between these thrust sheets are predominantly chlorite- and garnet-

bearing schist, quartzite with minor granite gneiss belonging to the Helang Formation and streaky biotite gneiss, quartzite, schist

and amphibolite of Bhilangana Formation. The Central Crystalline Group in this area is represented by psammitic gneiss and

schist of Pandukeshwar Formation and garnet, staurolite, kyanite bearing schists, sillimanite bearing migmatites of Badrinath

Formation. Amphibolites and undeformed younger Tertiary granites are the intrusive phases. Overthrust rocks from the Central

Crystallines are present as klippé within the Lesser Himalayan Belt.

3. Uttarakhand:Thrust Tectonics in Central Himalaya

Folded quartzite near Takula, Almora DistrictWild flowers in bloom

Overview

Uttarakhand is a hilly state in the northern part of India. It is commonly referred as ‘Dev bhumi’ (land of gods)

due to presence of numerous temples in the state. The northern part of the state is covered by high mountains

and large glaciers. Nanda Devi (7816 m), the second highest mountain in India is located in Uttarakhand. The

dense forest covering most of the state supports a high floral and faunal diversity. Many national parks and wild

life sanctuaries are present including Nanda Devi National Park and Valley of Flowers National Park, both

being UNESCO World Heritage Sites. The Jim Corbett National Park is a famous and the oldest tiger reserve

forest present in the Tarai region of Uttarakhand.

14


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Sight seeing at Rishikesh

Arrival Rishikesh

by bus

Day 2 Rishikesh-Srinagar Blaini Diamictite near Shivpuri; Tal Group and

Garhwal Nappe near Bayasi; Precambrian-

Cambrian boundary near Kauriyala; rocks of

Chandpur phyllite and Jaunsar Group of

Lesser Himalayas and North Almora Thrust

at Kirtinagar

Day 3 Srinagar-Joshimath Observing old workings for base metals; Rudraprayag and Joshimath are scenic

stromatolite at Rudraprayag, exposures of

Garhwal metavolcanics and MCT (Munsiari

Thrust) at Helang

Day 4 Joshimath-Hardwar Exposures of Higher Himalayan Sight seeing at Hardwar

Crystallines at Joshimath

Day 5 Departure Hardwar

Arrival New Delhi

Travel by road


Migmatite of Central CrystallinesShearing in chlorite schist of Helang Formation

IGC

DELHI 2020

15


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure Delhi Arrival Sightseeing at Bhimtal

Bhimtal Travel by road

Day 2 Bhimtal-Nainital Himalayan Frontal Fault at Kathgodam/ Sightseeing at Nainital

Haldwani; Main Boundary Thrust at Jeolikot;

rocks of Krol Group at Nainital; Krol Thrust

at Bhumiadhar

Day 3 Nainital-Kausani Ramgarh Thrust south of Gagar; Ramgarh Sightseeing at Kausani

Group and South Almora Thrust south of

Bhatelia, rocks of crystalline nappes of

Lesser Himalaya (Almora Nappe) and North

Almora Thrust at Someshwar/ Manan

Day 4 Kausani-Sattal Sightseeing at Sattal (Seven Lakes)

Day 5 Departure Sattal

Arrival Delhi

Travel by road


Kyanite schist of Almora crystallinesNorth Almora Thrust near Someshwar

16


Uttarakhand, in the western Himalayas, exhibits important geological sequences and thrust sheets. From north to south, the

fossiliferous sedimentary and meta-sedimentary rocks of Tethyan sequence lie north of South Tibetan Detachment (STD), the

medium to high grade metamorphic rocks of Higher Himalayan Crystalline (HHC) occur between STD and Main Central Thrust

(MCT) while the sedimentary and low grade rocks of lesser Himalaya occur between MCT and MBT. The southernmost ranges

are constituted by Neogene rocks of Siwalik Group which are thrusted over the alluvium along Himalayan Frontal Fault (HFT).

The Quaternary deposits are scattered as moraines and glacio-fluvial deposits in the higher reaches. These sediments also

occur as terraces and lacustrine deposits along the rivers in the middle and lower reaches and as alluvial fans, debri deposits

along the valleys. This field excursion would depict the diversity in terms of river morphology, sedimentary architecture and

processes in the cliff sections of terraces in mountain region. The focus will be on the study of fluvial sedimentary packages that

illustrate the response of the Ganga system to late Quaternary climate changes.

Alaknanda River with unpaired terracesConfluence of Bhagirathi and Alaknanda rivers at Devprayag

Badrinath Shrine

3. Uttarakhand:Late Quaternary Aggradation –Degradationof Alaknanda River

Overview

Uttarakhand comprising of Garhwal and Kumaon regions is largely a mountainous state in northern India. It is

known for places of spiritual importance and beautiful landscape. Traditionally known as the Land of Gods,

the state houses many glaciers including Gangotri and Yamunotri from where the rivers Ganga and Yamuna

originate. The Ganga River System is among the largest in the world. Originating in Garhwal Himalayas and

formed by the confluence of Bhagirathi and Alaknanda rivers, the Ganga travels about 2599 km through the

Himalaya and plains to finally join the Bay of Bengal. Uttarakhand offers excellent sporting opportunities like

river rafting, skiing and mountaineering.

IGC

DELHI 2020

17


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure Delhi: Arrival Rishikesh is the spiritual towns of

Rishikesh by road

Day 2 Rishikesh - Nandprayag Gravel dominated > 80 m high aggradational Scenic confluence of Alaknanda and

terrace sections at Ratura and Gauchar

marking the response of high monsoonal

rains during 52-32 ka interglacial MIS 3

Day 3 Nandprayag – Hardwar Terrace sections near Srinagar. Meandering The holy city of Hardwar offers a unique

Rampur

Day 4 Departure Hardwar

Arrival Delhi by road

mythological and religious importance.

Has sacred bathing ghats and river

bank temples

Bhaghirathi rivers at Devprayag

and straight incised morhology of spiritual experience. The evening prayer

Alaknanda River at the bank of the Ganga River is an event

to watch


Alluvial cut terrace (80 m high) of Alaknanda River

18

Gita updesh - Kurukshetra

Synoptic Geology

The NW-SE trending ridges of Delhi Supergroup in southern part and EW ranges of Siwalik belt in northern part constitute the

hardrock terrain covering 5 percent area of Haryana. The remaining 95 percent area is covered by loose to semi-consolidated

Quaternary sediments on gently slopping plains. The Quaternary sediments comprise a northerly thickening (> 400m thick)

column of alluvial, lacustrine and aeolian deposits calcretised at various levels. The aeolian deposits are common along the

western border as extension of Thar desert.

The sand dunes and sheets of stabilized and active nature are of aeolian origin at various phases. A number of disjointed

impressions of palaeodrainage are scattered all over the alluvial and aeolian plains. Among them, a segment of Vedic Sarswati

River near Fatehabad is the most prominent. Relicts of Harappan culture and civilization are also scattered

in northern and northwestern parts. The Quaternary deposits and archeological mounds of the state are

important archives of palaeohydrological, desertification processes. The excursion will show the

fluvio-aeolain transitions, Holocene limestone, sulphate bearing lake deposits and Harappan mounds.

along the

palaeochannels

palaeoclimatic conditions and

4. Haryana:Holocene Climate and Harappan Civilization

Stabilised Sand dune, FatehabadAerial view of palaeochannel of Saraswati

Overview

Haryana is a small state in northern India spreading over 44,212 sq km area. About 65 percent of its

population is engaged in agriculture. All villages stand connected with metalled roads. There is a network of

44 Tourist Complexes in the state.A large part of the state witnesses a semi-arid climate and lies in the Indus

plains near the northeastern border of Thar desert. Haryana finds mention in the great epic of Mahabharata.

Kurukshetra is the place of the epic battle between the Kauravas and the Pandavas.

IGC

DELHI 2020

19

Trip Plan No. 4: 3 Days 2 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure Delhi Alluvial–aeolian transition at Rohtak,

Arrival Hissar by road

Day 2 Hissar-Fatehabad- Cliff section of Ghagghar River, Gujri Mahal, Agricultural farms

Hissar by road

Day 3 Hissar- Delhi by road

Holocene carbonate lake deposits of Riwasa

and and sulphate lake deposit at Saherwa

Palaeochannel of Saraswati River(?),

Fatehabad


Section of Rakhigarhi cultural mound

A Harappan mound near FatehabadLimestone bearing lake deposit, Riwasa

20

Taj Mahal during night, Agra


Uttar Pradesh, located mainly in the Ganga plains, has a foreland with the Himalayas in its north. The Ganga, an axial river

originating in the Himalaya, is joined by several tributaries including Yamuna, Ramganga, Ghaghra and Gandak before draining

through Bihar and West Bengal into the Bay of Bengal.

Several kilometre thick column of sediments along the Ganga plains comprise mainly gravels in the north and sand-silt-clay in

the south. This field excursion along a part of the Ganga River is aimed to understand the geodiversity of this large river system in

terms of morphology, processes and sedimentation patterns in the middle reaches. The focus will be on the study of fluvial

sedimentary packages of cliff sections in the southern Ganga plains that illustrate the response of this system to late Quaternary

climate change.

5. Uttar Pradesh:Geodiversity of Ganga Dispersal System

Imambara, LucknowChaukhandi Stupa

Overview

Uttar Pradesh covering 2,36,286 sq km area is known for its heritage, etiquette, culture and bounties of

nature. It is considered to be the land of ancient cities and also the seat of Buddhism. Some of the greatest

monuments dot the state. It is the most populated state of India accounting for 16.4 per cent of the country’s

total population. It is the second largest state-economy in India. Two sacred rivers Ganga and Yamuna flow

through the state and form a perennial source of water.

IGC

DELHI 2020

21

Trip Plan No. 5 3 Days 2 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure Delhi

Arrival Kanpur

Day 2 Kanpur- Delhi by train Palaeobank cliff section near Narela and Red Fort, Kutub Minar, Lotus temple

Day 3 Delhi–Garh Mukteswar- Cliff sections of palaeobank, terraces and Holy ghats of Ganga and temples

morphology of Ganga river near

Garh Mukteshwar

Cliff section of the Ganga River near Kanpur

by train (Bithur section)

Yamuna banks in Delhi

Delhi by road


Cliff section of the Ganga River near Kanpur (Bithur section)

22

Hawa Mahal, Jaipur

Synoptic Geology

Rajasthan forms the north-western part of the Indian Shield and exposes a variety of rock sequences ranging in age from

Archaean to Quaternary. The cratonic nucleus in the western Indian Shield occupies large tracts in south and east Rajasthan

and is classified as Bhilwara Supergroup. It is bound on the west and southwest by Proterozoic mobile belt comprising

supracrustal sequences of Aravalli and Delhi Supergroups. An arcuate belt of low grade volcano-sedimentary rocks and

platformal sediments of the Vindhayan Group demarcate the eastern boundary of this craton.

Quaternary formations in Rajasthan state occur in the form of assorted sediments of aeolian, fluvial and lacustrine origin in the

Thar Desert in the western part. Rajasthan occupies leading position in the mineral map of India with almost one fifth of the total

working mines of the country. Ore deposits of metallic minerals for zinc, lead, copper and tungsten occur in Rajasthan besides

significant reserves of building stones, industrial minerals and semi precious gemstones.

Pb-Zn ore deposits occur in

d i f f e r e n t h o r i z o n s i n

Rajasthan. The deposits of

R a m p u r a - A g u c h a a n d

Bethumbi-Dariba-Rajpura

belong to the Archaean to

Lower Proterozoic Bhilwara

Supergroup, those of Zawar

are associated with the

Lower Proterozoic Aravalli

Supergroup and Kayar-

Ghugra with the Lower to

Upper Proterozoic Delhi

Supergroup.

6. Rajasthan: PalaeoproterozoicLead-Zinc Sulfide Metallogenesis inAravalli-Delhi Orogenic Belt

Overview

Rajasthan is the largest state of India occupying nearly 11 percent of the total Indian territory. The

northwestern part of the state is occupied by the Thar Desert that covers almost 32 percent of the total area.

TheAravalli Hill Range divides the state into two unequal parts and forms a prominent physiographic feature.

IGC

DELHI 2020

23

Geological map of Khetri Belt

Trip Plan No. 6a: Days 1 Nights

Starts: New Delhi

Finishes: New Delhi

2

Trip Description

Day 1 Delhi-Khetri- Jaipur. See the copper mineralization in tightly folded Pink city Jaipur is well known for palaces,

forts and the artifacts of traditional

Rajasthani culture

Day 2 Departure Jaipur Arrival

New Delhi by air

by road Proterozoic metasediments and operating

underground copper mines. Visit would reflect

upon the surface signature of the ore body

while covering the nature, controls and origin

of mineralization


Related Information

Khetri Copper belt, Jhunjhunu District

Khetri copper belt extends over a strike length of 80 km from

Singhania in the north to Raghunathgarh in the south.As many

as 45 deposits and prospects have been explored in and

around this belt

The mineralized zones are generally marked by gossan, old

workings, mine dumps and iron staining. The copper

mineralization,

is found in the metapelite and

metapsammite of the Proterozoic Delhi Supergroup.

Mineralization in the southern part of the belt is mostly along

shear and breccia zones.

manifested by disseminations of chalcopyrite,

pyrrhotite and pyrite,

24


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Sambhar is a large inland saline lake The salt production in operation.

up in the surrounding hills of Aravalli sanctuary

with a circumference of about 100 km

Day 2 Ajmer to Bhilwara via

Day 3 Bhilwara to Agucha This open cast multimetal mine provides Udaipur is known as City of Lakes

opportunity to study rich stratabound ore

mineralization, its structural control and

effects of metamorphism

Day 4 Departure Udaipur

Arrival New Delhi

by air

nestled

Arrival Jaipur by air Range Bird

Jaipur-Ajmer via Pushkar Lake and nearby religious

Sambhar Lake places

Geophysical exploration led to the Bhilwara is an old tribal town having a

Kayar Zn-Pb prospect identification of this zinc-lead deposit that thriving textile industry now. It is a big

extends for over one kilometre and is hosted centre for mining of industrial minerals

predominantly by the metapelites of the and manufacturing of refractories

Proterozoic Delhi Supergroup

Zn-Pb deposit and

halt at Udaipur


IGC

DELHI 2020

25

Trip Plan No. 6c: Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

4

Trip Description

Day 1 Departure New Delhi

Arrival Udaipur by air

Udaipur-Zawar-

Udaipur

Day 2 Udaipur-Rajpura-

Dariba-Chittaurgarh-

Bhilwara

Day 3 Bhilwara-Rampura

Agucha-Ajmer

mineralization, its structural control and

effects of metamorphism

Day 4 Departure Ajmer Arrival

New Delhi by train/road

Ancient Pb-Zn mining and smelting activity Known as City of Lakes, the historic city

in the region where dolomite hosted ore from of Udaipur is famous for the aesthetic

the Proterozoic metasedimentary water bodies and the palaces

lithopackage is being mined

A prominent gossan over a sulphide rich The historic city of Chittaurgarh is famous

zinc-lead ore, the origin and the controls of for its fort, and other palaces

mineralization

This opencast multi-metal mine provides Bhilwara has a thriving textile

opportunity to study rich stratabound ore and mining industry


26

Related Information

Agucha Zinc-Lead Deposit, Bhilwara District

The mineral deposit is located near Agucha (25 49’N:74 44’E) in Bhilwara district, and is being worked as an opencast mine.

Surface manifestation of this deposit is a weak gossan.

The Zn-Pb mineralization in Agucha occurs within high-grade metapelitic rocks that are associated with amphibolite and calc

silicate rocks. This deposit is stratabound and of SEDEX type. The mineralization consists of sphalerite, pyrite, pyrrhotite,

galena, and traces of chalcopyrite, arsenopyrite and sulphosalts. The ore is recrystallised and laminated owing to its proximity to

a ductile shear zone.

o o

o o o o

Bethumbi-Rajpura-Dariba Lead-Zinc Belt, Rajsamand District

This N-S to NE-SW trend belt extends for about 17 km forming a sickle shaped structure with convexity towards west. Major

prospects occur between Surawas (25 05’N:74 14’E) in north to Dariba (24 57’N:74 07’46”E) in south within a tight,

overturned synform that truncates against a ENE-WSW fault at Surawas.

A diagnostic gossan is developed over a part of the ore deposit. The main Pb-Zn sulphide ore bearing horizons are confined to

mica schist, metachert, with lenses of dolomitic marble and carbonaceous schist overlying the Archaean basement. Sphalerite,

galena, chalcopyrite and pyrite form the main sulphide ore minerals. It is considered to be a SEDEX type of deposit.

Geological map of Agucha Belt

IGC

DELHI 2020

27

Zawar Lead - Zinc Belt, Udaipur District

Zawar (24°17’N:73°41’E) lead-zinc belt is located about 40 km south of Udaipur city in the state of Rajasthan and extends for

about 20 km. The area around Zawar village was an important site for lead-zinc--silver mining in ancient India and continues to

be so even now.

The rock sequence exposed in the Zawar belongs to the Lower Proterozoic Aravalli Supergroup. It includes thickly bedded

polymictic conglomerate and grits; quartzite, greywacke, dolomite and its variants; phyllites and slates with minor interbands of

quartzite and dolomite. Presence of primary and well-preserved multi-deformational structures in the area makes it important for

understanding the controls of mineralization.

The Pb-Zn mineralization in Zawar area is stratabound and confined to dolomite and its variants. Sphalerite and galena are the

main ore minerals for zinc and lead and also produce subordinate cadmium and silver. Studies show that the Zn-Pb metals

present in the host dolomite and associated carbonaceous phyllite formed proto-ore that was later remobilized in dilational or

extensional fractures developed during deformation of the Zawar rocks. Dewatering of basinal fluids was probably responsible

for remobilization of ore and formation of Pb-Zn deposits.

Geological map of Zawar area

28

Jodhpur Fort

Synoptic Geology

Volcanism initiated as basaltic eruption with occasional andesite or trachybasalts followed by voluminous outpouring of

peralkaline and peraluminous rhyolite, basalt, dacite and trachyte flows and terminated with the outburst of ash flow deposits.

The other rock types associated with rhyolite are trachyte, dacite, pithstone, welded tuff, lithic and crystal ash, ignimbrite,

obsidian, pyroclastic slates, agglomerate, volcanic breccia and volcanic conglomerate. Majority of the acid volcanics are high

potassic and few are calc-alkaline or low potassic in composition. Essentially eruptions were under terrestrial conditions through

fissures, shield volcanoes and central cones. The “hot spot” triggered volcanism in an extensional tectonic regime of continental

crust had initial basaltic magma generated at greater depth. This magma while migrating upwards supplied additional heat for

the partial melting of lower sialic crust resulting in the generation of felsic magma. The crustal extension has helped in the upward

advancement of the felsic magma.

6. Rajasthan:Malani Volcanic Province Hot SpotTriggered Felsic Volcanism

–

Geological map of Malani Volcnaic Province

Overview

The Neoproterozoic Malani bimodal volcanics constitute the largest suite of anorogenic acid volcanics in

India that has an aerial spread of over 3100 km2 in the state of Rajasthan. The 745 ± 10 Ma old volcanism

succeeded the granitic activity ofAbu Pluton and ceased before the onset of Marwar sedimentation.

IGC

DELHI 2020

29

Trip Plan No. 6d: Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

4

Trip Description


Arrival Jodhpur by air

Jodhpur-Mandore-

Jodhpur

Day 2 Jodhpur-Kankani-

Kailana-Jodhpur

Porphyritic rhyolite overlain by

Neoproterozoic continental sediments of

trans Vindhyan rocks (Marwar Supergroup)

Day 3 Jodhpur-Korna-Mandli-

Jodhpur

joints

Day 4 Departure Jodhpur


Complete ignimbrite sequence represented Jodhpur fort and palaces

by layered tuff, welded tuff, lithic and vitric

tuff, ash beds and glass shards.

These are overlain by thin flows of rhyolite

Mesoproterozoic Delhi Supergroup

overlain by Malani Rhyolite and ash beds.

Central and fissure eruptions. Malani fossil

cone, agglomerate, perlitic tuff and columnar


30

Synoptic Geology

Quaternary deposits of variable thickness occur all through the Thar Desert. These sediments of aeolian, fluvial and lacustrine

nature form undulating plains between the hill ranges occupied by the hard rocks. The aeolian deposits formed over 200 ka ago

display various types of sand dunes with calcrete of pedogenic and non-pedogenic origins. Alluvial deposits are abundant in

northern part of the desert and along the ephemeral river courses in the western part. The lake sediments spanning the past 40

ka, consist of evaporite and silt-clay and occur as lenses in the abandoned and ephemeral lakes. Archaeological evidence of

human interaction with the desert is present at several places.

6. Rajasthan:Thar Desert and its Evolution

Sambhar lake is Asia’s largest saline lakeSand dune field near Jaisalmer

Overview

Thar Desert in western India covers around 2,59,000 sq km in the states of Rajasthan, Gujarat, Haryana and

Punjab. It is characterized by hot and dry climate, aeolian landforms, salt marshes and saline lakes. The

rainfall is meager and distributed erratically. The mean temperature varies between 24 - 26 C in summer to

4 -10 C in winter. The Thar is one of the most populous and fertile deserts of the world. The main occupation

of the people is agriculture and animal husbandry. Acolorful culture prevails in the desert. The people have a

great passion for folk music, dance and poetry. Jaisalmer, Bikaner and Jodhpur are main cities located in the

heart of the Thar Desert

o o

o o

IGC

DELHI 2020

31

Trip Plan No. 6e : Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

4

Trip Description

Day 1 Departure Delhi. Arrival

Jodhpur by air

Mehrangarh Fort, Umed Place Museum

and

Day 2 Jodhpur-Jaisalmer Piedmont sections of aeolian and colluvial

units. Parabolic dunes. Fluvial gravels bed

in arid setting

Day 3 Jaisalmer-Kuldhara-

Jaisalmer

active dune field of Sam deposited around

14 ka

Day 4 Jaisalmer-Jodhpur by

Road. Jodhpur-Delhi

by air

Jodhpur, the “Sun City”, sits atop the red

sandstone of Cambrian age. Features

Balsamand Lake

Abandoned village Kuldhara on the bank of Traditional desert life style, stone carved

Sam- ephemeral river. Spectacular, unvegetated, forts and havelis. Sunset view at Sam


Trip Plan No. 6f: Days 2 Nights

Starts: New Delhi

Finishes: New Delhi

3

Trip Description

Day 1 Delhi-Jaipur by road Visit to Asia’s largest saline lake “Sambhar

Llake”

Day 2 Jaipur-Pushkar Dune, fluvial and lacustrine sequences near

Budha Pushkar

Day 3 Jaipur-Chandwaji-New

Delhi by road

alluvial and aeolian deposits

Pink City Jaipur, palaces, observatory

Holy Pushkar Lake, palaces and other

places of tourist interest like forts in

Jaipur

Visit to 74-16 ka old dunes around Amarsar.

Chandwaji River sections for colluvial,


32

Narayan Sarovar

Synoptic Geology

The Kutch region comprising the Mainland, Coastal plains and the Rann areas, exposes Mesozoic and Tertiary sedimentary

sequences. It also exposes alkali effusive volcanic sequences in Anjar and Bhachau areas. The volcanic and associated

sedimentary rocks atAnjar show high concentration of REE.

The Mesozoic rocks occur as intertrappeans within the Deccan Traps at several places in Kutch peninsula. These

intertrappeans have yielded fossils of plants, bivalves and fish. The dinosaurian remains (egg clusters and bones) are also

reported fromAnjar and Fatehgarh.

The Tertiary rocks are mainly exposed all along the western, southern and southeastern parts of Kutch, extending from Lakhpat

in the west to as far as Wandh in the east. The oldest Tertiary rocks directly overlying the Deccan Traps belong to the

Palaeocene age. Lignite is associated with the Early Tertiary rocks. Eocene variegated clay, shale and limestone yield abundant

foraminifers.

7. Gujarat:Stratigraphic Architecture of Rift toPassive Margin Evolution in Kutch Basin

Dinosaur egg remains at RahioliVertically layered gabbro dyke intruding the coarse gabbro, Nirwandh plug

Overview

The geology of Gujarat demonstrates a classic sequence of marine Mesozoic-Tertiary sediments, the

eruptive Deccan Trap basalts along with the oldest Precambrian metamorphics and youngest Quaternary

sediments. The Deccan Volcanics and its intrusive variants, forming a major volcanic episode commencing

from the Cretaceous and terminating in the Eocene, separate the Mesozoic and Tertiary rocks.

A younger intrusive phase, confined to the Mainland areas is represented by alkali basalt plugs, is often

associated with pyroclastics and alkali lava flows (basanite and peridotite). These also predate the main

Deccan Trap activity and some of these plugs contain mantle xenoliths of spinel lherzolite and dunite.

IGC

DELHI 2020

33

The Oligocene is represented by the sandy limestone, coralline limestone, glauconitic clay, marl and siltstone whereas

the Oligocene to Lower Miocene has yielded a rich assemblage of mammalian and other vertebrate fossil fragments. The

Lower to Middle Miocene sediments comprise green siltstone, fossiliferous and gypseous marlite and are overlain by

Pliocene sandstone – siltstone – clay yielding avian egg shells.


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi.

Arrival Bhuj by air

Bhuj-Anjar

Day 2 Bhuj-Matanomadh-

Narayan Sarovar

lignite

Day 3 Bhuj-Nakhtrana Study of alkaline plugs of mainland Kutch Haji Pir (famous Dargah)

Day 4 Departure Bhuj Arrival

New Delhi by air

K-T boundary with special emphasis on ash Mandvi Beach in Gulf of Kutch and

bed containing iridium. Mandvi Palace

Study of dinosaur fossils at Anjar

Eocene to Cenozoic carbonate rocks Lakhpat Fort and Narayan Sarovar

including Nummulitic limestone. Eocene (westernmost point of India)


34

Location of Surat in Gujarat

Industry in Nutshell

Surat (21.17°N: 72.83°E), a historical port on the west coast of India, is the second largest and one of the fastest growing cities of

Gujarat. From a humble beginning, the diamond industry in Surat went on to become one of the largest centres of c & p of rough

diamonds (< 5 cents > 5 carats) in the world today. Varacha Road, a street in Surat is the main hub of diamond c & p industries.

The diamond producing countries send their rough diamonds after sorting according to size, shape, colour and quality for cutting

and polishing to India through the network like DTC with the Kimberly Process Certificate, certifying that they are from conflict-

free sources. Out of about 8,000 diamond cutting and polishing units in the country, employing between 800,000 to 1,000,000

workers, Surat alone has more than 3,000 diamond c & p units, that employ more than 400,000 workers.

The saying goes that eleven out of twelve diamonds set in jewellery in the world are cut & polished in India. Traditionally the 'hira

karigars' (diamond artisans) shape the rough diamonds using 'ghantis' (polishing wheels). Of late large factories have come up

using modern machinery.

7. Gujarat:Surat – Diamond Cutting and Polishing Hub

Diamond market in SuratThe cut and polished diamonds

Overview

This visit will expose the participants to the methods of cutting and polishing (c & p) of diamonds, mainly the

small ones, by traditional and sophisticated processes. The methods include cutting, bruting (rough shape-

table, bottom and top), polishing, checking and assorting of diamonds.

IGC

DELHI 2020

35


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Visit to IDI, Surat Local sight seeing

Surat by air

Day 2 Visit to cutting and Visit to Diamond C & P units Local marketing

polishing units

Departure Surat

New Delhi by air

Arrival

Arrival


Boat RaceCity of Surat

36

Interbanded barite – flourite, Pakhal Group.

Synoptic Geology

The Precambrian crust of Central India with Bundelkhand Craton (BKC) in the north and Bastar Craton (BC) in the south was

accreted along a ENE-WSW trending Proterozoic Central Indian Tectonic Zone (CITZ), spread over the states of Madhya

Pradesh and Maharashtra.

Tonalite-Trondhjemite-Granodiorite (TTG) basement suite of 3.3Ga with abundant metasedimentary enclaves dated between

2.5-2.6 Ga constitute the prominent rock type of the Bastar craton reflecting a major interval of crustal accretion in this region.

The Bastar craton is divided into eastern and western parts with Dongargarh granite as the dividing line. It is also characterized

by development of major linear structural trends, which include the N-S trending Kotri, NW-SE trending Ghot-Chamorsi, NNW-

SSE trending Thanewasna - North Godavari and ENE-WSW trending Gadchiroli lineaments. These lineaments have subjected

the craton to varying degrees of shearing and host the copper and barite mineralization of IOCG type at Thanewasna.

8. Madhya Pradesh and MaharashtraArchaean Craton and Mineralization

:

Layered anorthosite -gabbro, GondpipriThe Archaean Amgaon Gneiss,Gondia

Overview

The Central Indian Shield is a mosaic of northern and southern crustal provinces separated by the Central

Indian Tectonic Zone (CITZ). Bastar craton with an Archaean nuclei is a part of the southern province. It is

bound by two mobile belts in the northwest and southeast besides Proterozoic rifts of the Mahanadi to the

northeast and the Godavari to the southwest. The Bastar craton is a major metallogenic province with

deposits of copper, iron and manganese.

IGC

DELHI 2020

37

Autolithic limestone breccia of Pakhal Group at GondpipriIron oxide breccia at Thanewasna copper deposit


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Nagpur by air.

Chandrapur-Wardha-

Warora-Chandrapur

Day 2 Chandrapur-Gondpipri-

Chandrapur

Cu mineralisation at Dubarpet, Heti Ni-PGE

prospect, Thanewasna IOCG-type copper

deposit

Day 3 Chandrapur-Nagpur Mul granite and barite mineralisation, Sight seeing at Nagpur

Proterozic Sakoli metasediments,

Pular-Parsori gold deposit in Sakoli

metavolcanics

Day 4 Departure Nagpur

Arrival New Delhi

air

Barite-flourite deposit at the contact of Mahatma Gandhi Ashram at Sewagram,

Gondwana Group and Proterozoic Pakhal Tiger Reserve, Chandrapur

Group in Dongargaon

Boundary fault between Archaean Basement Ancient Markanda temple

and Proterqzoic Pakhal cover sediments,

by


38


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Jabalpur by air.

Jabalpur-Bedaghat-

Jabalpur

Day 2 Jabalpur-Malanjkhand Porphyry copper deposit Kanha Tiger Project

Day 3 Malanjkhand-Jabalpur

Departure Jabalpur


Bedaghat marble section along Narmada Water sports along the river

River, evidence of neotectonic activity


Narmada River veering through marble rocks, JabalpurMalanjkhand copper mine

Related Information

Malanjkhand porphyry copper deposit (2490±9 Ma) is the largest single copper deposit known in the Peninsular India. Located

in the Balaghat district of Madhya Pradesh, it occurs close to a complex junction of the Sausar, Sakoli and the Kotri - Dongargarh

belts. Copper mineralization in this deposit is localized in the quartz reefs associated with the granite. The ore zone extends for

about 1.9 km with an average width of about 65 m.

Total resources of about 235 million tonnes of ore at 1.28 percent of copper are estimated for this deposit. The copper ore also

produces significant amount of molebdenum, gold and silver.Presently, ore is being exploited by open cast mining.

IGC

DELHI 2020

39

Sevagram Ashram (last residence of Mahatma Gandhi)

Synoptic Geology

The Sausar Mobile Belt, representing the southern belt of the CITZ in the central sector, comprises folded and metamorphosed

non-volcanic and Mn-rich sediments intermixed with reworked basement gneiss, migmatite and granulite. It occurs in tectonic

contact with the underlying Tirodi biotite gneiss.

The granulite facies rocks occur in two distinct belts flanking north and south of the Sausar Group of rocks. The peak P-T

conditions for the granulite facies metamorphism of the Sausar Belt are constrained at 8-10.5 kb and 850°C. It was followed by

isothermal decompression to 6-4 kb at 750-850°C, indicating denudation of 13-14 km of crustal material.

On the basis of 950 Ma Ar/ Ar cooling age and 860-Ma K-Ar mineral isochron age from the Tirodi biotite gneiss, the main phase

of Sausar orogeny is interpreted as the ~1000 Ma Grenvillian event.

40 39

8.Sausar Mobile Belt ofCentral Indian Tectonic Zone

Madhya Pradesh and Maharashtra:

Tirodi biotite gneiss forming basement of Sausar metasediments

Overview

The CITZ is an ensemble of several low- to medium-grade supracrustal belts, gneisses, granitoids and a few

linear tracts of granulite belts. A number of crustal scale shear zones define the boundaries of the

supracrustal belts and discrete terrains. It is a ENE–WSW trending, 500-km-long and 0.2 to 4-km-wide,

ductile shear zone characterized by the presence of mylonite and phyllite and minor cataclasite. Three

mobile belts with Mahakoshal in the north, Sausar in the south and Betul in the middle are its important

constituents. Polyphase tectonothermal events spanning from Paleoproterozoic to early Neoproterozoic are

recorded in the CITZ. A northward dipping subduction system leading to continent-continent collision is

proposed for its growth and assembly at ca. 1.5 Ga.

40


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Nagpur by air

Day 2 Nagpur-Chikhaldara-

Betul

Day 3 Betul-Sausar- Sausar Group rocks and basement of Tirodi

gneiss, syn- sedimentary manganese

deposits, ultra-high-temperature granulite



CITZ, southern granulites of Bhandara, Mahatma Gandhi Ashram at Sewagram,

Proterozoic Sakoli metasediments Tiger Reserve, Chandrapur

Gavilgarh fault zone, neotectonic activity Chikhaldara hill station, Gavilgarh fort

Ramtek and Pench Tiger Projects

Mansar-Nagpur


Cuesta of Gavilgarh Fault Zone, Amaravati

IGC

DELHI 2020

41

Maa Sharda Temple, Maihar

Synoptic Geology

Microbiota appeared on earth before 3.8 Ga and flourished during the Proterozoic time.A long-standing problem in Precambrian

palaeobiology has been the rarity of calcifying cyanobacteria in comparison to their proliferation in the Cambrian. The microbial

life in Vindhyan sediments includes algal stromatolites in Semri and Bhander Groups, brachiopods, annelids and arthropod,

besides microfossils, plant and fungal remains.

Abundance of mat-related sedimentary structures in the siliciclastic rocks of the Vindhyan Group provides yet another

dimension to the understanding of the Proterozoic bio-sedimentology.

Spectacular development of the microbialite colonies, profusion of mat-induced structures and the sediment – early life

interaction can be glimpsed through the excursion.

8.Precambrian PalaeobiologyA Window to the Microbial Earth

Madhya Pradesh and Maharashtra:–

Munchuriophycus, Churhat SandstoneMicrobial mat, Sirbu Shale

Overview

The Vindhyan Supergroup is 1 to 4 km thick and extends for about 160,000 km in a curvilinear basin

surrounding the Bundelkhand granite massif. It is limited by the Son-Narmada-Tapti lineament in the south,

the Great Boundary Fault in the west and the Ganga plains in the north. These rocks are unmetamorphosed,

very less deformed, subdivided into Semri, Kaimur, Rewa and Bhander Groups and represent shallow

marine environment in an intracratonic basin.

Vindhyan sedimentation commenced around 1400 Ma and continued till the end of the Proterozoic (~ 570

Ma). Vindhyan-equivalent strata is represented in Himalaya by Simla Slate, Hazara Slate and Haimanta

Group. The Vindhyan Basin is known for the resources of limestone, diamond and dimensional stone.

2

42


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Khajuraho by air

Day 2 Khajuraho-Maihar-

Lilji Nala-Beta-Maihar

Day 3 Maihar-Churhat and

the area around Satna



Visit to the world heritage site of about 1000- World-famous Khajuraho Temples

year-old Khajuraho Temples

Exquisite signatures of microbial mat Maihar is a historical city. It finds an

influence on Precambrian siliciclastic system important place in Indian classical music

Profuse microbial mat features in Churhat

Sandstone and Koldaha Shale. Evidence of

oldest multicellular lifeform on earth


IGC

DELHI 2020

43

View of Khajuraho Temple

Synoptic Geology

Bundelkhand Craton is represented mainly by the Archaean cratonic mass of the Bundelkhand massif bordered by the arcuate

Proterozoic Vindhyan basin to the northwest and west and the Nagpur-Chhindwara-Bhander-Balaghat mobile belt towards the

south and east. The PDB, occupying the northern margin of the Vindhyan Basin in Panna and Chhatarpur districts of Madhya

Pradesh, is 150 km in length. Primary source rocks occur at Majhgawan, Hinota and the Atri-cluster. Innumerable small shallow

conglomerate and gravel diamond mines exist.

The Majhgawan-Hinota lamproites are intruded into the Semri and Kaimur Groups of the Vindhyan Supergroup. The lowest

member of the Semri Group, rests directly over the basement rocks (Bundelkhand granite and the Bijawar Group). There is no

evidence of any major tectonic disturbance along the contact zone of the Vindhyans with the underlying Bijawars or the

Bundelkhand massif. The Vindhyan beds in general strike ENE-WSW and dip 5° to 10° to the south, although some of the lower

formations have dips up to 25°. Some of the structures are attributed either to submergence of the basin or irregularity in the

initial topography of the basement .

8.Panna Diamond BeltA Historical Diamond Mining Centre

Madhya Pradesh and Maharashtra:–

Geological map of Majhgawan lamproite bodyImage of the Majhgawan lamproite body

Overview

The diamondiferous rock at Majhgawan (24°38'30"N: 80°02'E), near Panna, described as diamondiferous

green mud during early part of the 19 century, was discovered during the 13th centuryAD. Thus, Majhgawan

is the first-known primary source of diamonds in the world. The region is also known for extensive secondary

diamond-bearing gravel and conglomerate. The conglomerate and gravel have been exploited for diamond

since pre-historic times. The Majhgawan lamproite is too small to be considered as a source for the diamonds

found in the conglomerate and gravel, and thus the primary source(s) for these alluvial diamonds remain

elusive. The primary and secondary diamond deposits together constitute the Panna Diamond Belt (PDB).

th

44

Trip Plan No. 8e: 4 Days 3 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Majhgawan mine. Diamond Processing Unit

Arrival Khajuraho by air

Khajuraho-Majhgawan

Day 2 Khajuraho-Shahidan-

Hatupur section-

Khajuraho

Day 3 Khajuraho-Bunder

project-Khajuraho

Day 4 Departure Khajuraho


Visit to the world heritage site to

Khajuraho Temples

Extensive historical secondary diamond Visit to Panna Tiger Reserve

workings; diamond mines

Diamondiferous lamproites of Atri cluster


Regional map showing the Vindhyan basins

IGC

DELHI 2020

45

Chaitya and Vihara types of caves, Ajanta

Synoptic Geology

The Deccan Volcanic Province (DVP) is one of the largest continental flood basalt provinces of the world occupying an area of

over 5,00,000 sq. km. Popularly known as the Deccan Trap due to its step like appearance, the province derives its name from a

Sanskrit word Dakshin meaning south or southern and a Swedish word Trapp/ Trappa meaning stair. Deccan Traps occupy

nearly 75 percent of Maharashtra and also extend to the states of Karnataka, Andhra Pradesh, Gujarat, Madhya Pradesh and

Jharkhand.

The lava pile has a maximum thickness of over 1.5 km in the western parts of India that gets reduced to a few tens of metres near

exposed margins. The DVP is largely made of basaltic lava flows with subordinate intrusive bodies and very low proportion of

pyroclastics. The lava flows are nearly horizontal over vast distances but assume measurable dips in the western parts near

Mumbai and in Satpura Ranges. The average thickness of the individual lava flows is around 20 m and they can be traced for few

to over hundred kilometres. Majority of the individual lava flows exhibit pahoehoe or a`a morphology. The rocks are mainly

tholeiitic basalt with minor picrite. The intratrappean fossils provide an Upper Cretaceous to Lower Eocene age whereas the

isotopic data limits the eruption from 69 to 64 Ma with a peak around 65 Ma.

9. Maharashtra:The Deccan Volcanic Province

Pentagonal and hexagonal geometry of

the cooling joints in aa flow at Ajanta

Western Ghats escarpment as seen from Mahabaleshwar

Overview

Maharashtra contributes to about 15 percent of the country’s industrial output. It is the third largest state and

Mumbai the largest city of the country is the State capital. It is bound by the Arabian Sea in the west. The

Sahyadri Range or the Western Ghats, extend parallel to the coast flanked by the Konkan plains on the west

and the Deccan plateau in the east. Major rivers like Godavari and Krishna descend from the Sahyadri and

drain into the Bay of Bengal forming enormous river basins.

The excursions are planned in the southwestern part of Maharashtra and originate from the cities of

Aurangabad and Pune.Aurangabad (19° 53' 47"N: 75° 23' 54"E) is a historic city and now the tourism capital

of Maharashtra due to its vicinity to the famousAjanta and Ellora caves.

46


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Aurangabad

by air

Day 2 Aurangabad - Lonar

crater-Aurangabad

Day 3 Aurangabad -

Contributions of geological studies in

preservation of ancient monuments

Day 4 Departure Aurangabad

Arrival New Delhi

by Air

Observe lava flows and meteorite impact The panoramic Lonar Lake occupying

crater for related structures the circular crater

The morphology of the Deccan Traps and the Ellora caves rank among the largest

Pitalkhora- internal features of the pahoehoe lava flows. monolithic structures in the world. These

Ellora caves- also feature in the list of World Heritage

Aurangabad sites


Panoramic view of Ajanta Caves

IGC

DELHI 2020

47

Related Information

The Lonar Crater

Lonar (19º58’N: 76º31’E) is located at a distance of about 125 km northeast of Aurangabad. The ~ 50,000-year-old Lonar crater

has an almost circular outline measuring 1830 m across and a depth of 150 m. The area around the crater is covered by the

basaltic flows of DVP and is capped by ejecta blanket, comprising angular fragments. The idea of Lonar

crater being volcanic in origin prevailed for quite some time till the theory of its being carved due to the impact of extra-terrestrial

body was proposed by La Fond and Dietz (1964) citing youthful morphology and presence of sub-surface breccia as evidence.

As the only known terrestrial impact crater in basalt, the Lonar crater therefore provides unique opportunities for comparison with

craters in lunar maria and lunar samples of shocked basalt.

It now occurs as a saline lake showing presence of methanogens of diverse origin.

are exposed on the hill slopes. The caves have

been excavated in the lower flow and consist of 18 units. Both the lava flows

several metres thick,

The Pitalkhora Caves are located about 90 km northwest of Aurangabad and mark the beginning of a glorious tradition of rock-

cut cave architecture in the Deccan Traps which lasted for over a thousand years, resulting in more than 1200 caves, with the

finest examples atAjanta, Ellora and Elephanta. There are 14 caves at Pitalkhora dating back to 1st century B.C. Ten of these are

located on the right bank and four on the left bank of a steep narrow gorge carved out by the Aruna River. The lava flow in which

the caves at Pitalkhora are excavated has pahoehoe morphology. At the base of cave no. 9, the pahoehoe flow lobes are

underlain by a green interflow horizon (bole).

Ellora is located 29 km northwest of Aurangabad and is well known for its monumental caves. The cave temples of Ellora are the

product of three religious faiths, each represented by elaborate carvings of

each faith. Cave no.16 carved out from ~ 300000 cubic feet of rock and known

as 'Kailash', is the largest and the best of all Ellora excavations.

The Ellora caves are located at the foot of a N-S trending hill that rises to about

160 m above extensive plains of the Shivna River to the west. Two basaltic

compound pahoehoe flows

Pitalkhora Caves

Ellora Caves

A view of the monolithic Kailash Temple and the rock-cut face

exposing a stack of numerous pahoehoe flow lobes.

48

display many features typical of the inflated pahoehoe lava lobes. The natural processes of weathering, scarp retreat and biotic

interference have had a serious deleterious impact on the sculptures and paintings in the caves and their environment.

Ajanta Caves

The rock-cut caves of Ajanta belong to the period between 2nd century BC to

the 6th century AD and are located about 104 km from Aurangabad. After the

decline of Buddhism in the region, these caves lay buried under a debris cover

in the jungle clad slopes till 1819, when they were rediscovered by chance.

The Ajanta Caves (30 in number) are excavated in a 76-m-high semicircular

escarpment carved out of compound pahoehoe lava flow by the Waghur River

that descends in a waterfall beyond the last cave. The area around Ajanta

Caves exposes three lava flows. The lower and upper lava flows are a`a in

nature whereas the middle flow has pahoehoe morphology. The individual lava

lobes display various features such as reddened flow unit contacts, pipe

vesicles, crack infilling structure (inflation cleft) and ropy structure. A variety of

cavity minerals including different species of zeolites can be seen in small vugs

or veins in the vesicular crust of many lobes.

A view of a rock-cut pillar in Kailash Temple Complex at

Ellora showing a stack of many pahoehoe lava lobes

Delicate carving in vesicular part of pahoehoe flow in cave 2, AjantaAjanta Caves

IGC

DELHI 2020

49

Sinhgarh Fort

Synoptic Geology

Pune area marks a transition in the style of eruptions from the dominantly compound pahoehoe lava flows in the lower parts to

largely simple lava flows in upper parts of the lava pile. The excursion passes through the Western Ghat crest zone and the

adjoining main Deccan Plateau cutting across the middle and upper parts (Poladpur, Ambenali, Mahabaleshwar Formations) of

the Western Deccan Province. Besides, there would be opportunities to sample the least contaminated part (Ambenali chemical

type) of the Deccan lava sequence as well as the red interflow horizons that probably represent the pyroclastic component of the

Deccan Volcanic Province.

Highland laterite capping has also developed at many places over the Deccan lava. Koyna area, ca 120 km south of Pune,

regularly experiences Reservoir Induced Seismicity (M = 6.3).

aá

Max

9. Maharashtra: The Western Ghats

Vesicle cylinders in the pahoehoe flow, PuneUpper clinker in the aá flow, Pune

Overview

Pune is the eighth largest metropolis in India and the cultural capital of Maharashtra. It is located due

southeast of Mumbai on the main Deccan Plateau. The landscape is characterized by a broad, flat-bottomed

valley that is bounded on its southern side by a nearly east-west trending “Katraj” Hill Range.

50


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Pune by air

Day 2 Pune - Panchgani -

Mahabaleshwar

the upper parts of the lava pile. Note changes

in the internal structure of different lava flows

near Mahabaleshwar

Day 3 Mahabaleshwar -

Koyna - Pune

Day 4 Departure Pune Arrival

New Delhi by air near Pune and in museums

Sinhagad Fort sitting atop a Deccan Trap Pune has many temples, museums and

section on a 1312-m-high hill scenic places in the vicinity

Observe typical features of inflated pahoehoe Panchgani and Mahabaleshwar are hill

lava lobes in the bottom part and aá flows in stations with lush evergreen forests.

These offer an excellent panorama

of the Tableland. Scenic Venna lake

Highland laterite over Deccan basalt. Koyna Panorama of the Deccan Volcanic

Reservoir known for its seismicity Province and the picturesque Koyna

reservoir

Beautiful specimens of cavity-filling

minerals


Panchgani Tableland

IGC

DELHI 2020

51

Map showing the Trans-Deccan Straits

Synoptic Geology

The basaltic flows exposed in the quarries near Rajahmundry have been traditionally regarded as part of Main Deccan Volcanic

Province with lava flows travelling along river valleys or subterranean tunnels. Later this has been substantiated by

magnetostratigraphy and geochemical similarities between basaltic flows of Main Deccan Volcanic Province and those of

Rajahmundry.

9. Maharashtra, Madhya Pradesh and Andhra Pradesh:Cretaceous-Palaeocene Marine Sea-wayacross Deccan Trap Province

Intertrappean section near Jhilmili village, Madhya.PradeshIntertrappean section near Gowripatnam, Andhra Pradesh

Overview

The Deccan volcano-sedimentary sequences (intercalated with Deccan volcanic flows), informally

designated as intertrappean beds, are traditionally regarded as terrestrial lacustrine strata deposited on the

topographic lows during the quiescent periods of volcanism. However, introduction of bulk screen-washing

techniques in early eighties of last century resulted in the discovery of many new groups of vertebrates in

addition to gastropods, ostracods, and charophytes from these beds. Some of the Maastrichtian

intertrappean beds, such as Asifabad (A.P.), Nagpur, and the Lameta Formation of Pisdura, Dongargaon

(Nand-Dongargaon basin, Maharashtra), which lie along the Godavari graben on the eastern margin of

Deccan Volcanic Province yielded predominantly brackish water to marine fishes representing the bottom-

dwelling skates and rays.As marine pycnodontid fish remains and foraminifers are also known from the Early

Palaeocene intertrappean beds of Rajahmundry, it has been suggested that a marine sea-way named as

“Trans-Deccan Straits” existed across the Deccan Volcanic Province connecting the southeastern coast with

the western coast along the Godavari graben and Narmada lineament. Recently, this has been confirmed by

the discovery of planktonic foraminifers from the Early Palaeocene intertrappean beds of Jhilmili

(Chhindwara district, M.P.) in central India.

52

Based on biostratigraphy of the intertrappean beds, radiometric dates of the basaltic flows and geochemical correlations with the

main volcanic province, the lower traps underlying the intertrappean beds have been correlated with C29r and the upper traps

with C29r/C29n reversal boundary. The eastern basaltic flows exposed at Asifabad, Nand-Dongargaon basin and Nagpur are

correlatable with Poladpur-Ambenali formations of Western Ghats on the basis of geochemical signatures.

Map showing the distribution of Deccan Traps in peninsular India and route map of field excursion

Location map of Deccan Trap and intertrappean beds near Rajahmundry

IGC

DELHI 2020

53


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi. Papi Hills. Scenic Godavari

Arrival Rajahmundry

by air

Day 2 Rajahmundry -

Mancherial - Wardha the right bank of River Godavari near

Rajahmundry. The intertrappean beds of

Asifabad

Day 3 Wardha - Pisdura -

Dongargaon - Pavna -

Wardha

Day 4 Warda - Nagpur

Departure Nagpur.


Deccan intertrappean beds exposed on

Dinosaur coprolite, bone and egg nesting

sites

Takli intertrappean beds that produced Sight seeing in ‘Orange City’ Nagpur

marine fish remains, GSI museum



Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Nagpur by air

Nagpur - Wardha -

Nagpur

Day 2 Nagpur - Chhindwara - Jhilmili intertrappean beds near Chhindwara

Nagpur

Day 3 Departure Nagpur Sight seeing in Nagpur city


Takli intertrappean beds that produced Sight seeing in ‘Orange City’ Nagpur

marine fish remains. GSI museum

that yielded planktonic foraminifers


54

Vertebraria remains within carbonaceous shale

Synoptic Geology

The Gondwana sedimentation is considered to have initiated in India during the late Carboniferous after the Hercynian Orogeny

and is coincident with the clockwise rotation of the supercontinent. It began with glacio-marine and rift-related

sedimentation, transgress into coarse clastic-dominated proximal sequence. The coal-bearing formations in fault-controlled

sub-basins represent the post-glacial warm period during the Permian. Early Cretaceous termination of Gondwana

sedimentation is linked to the outpouring of the Rajmahal Group of lavas.

The Damodar Valley belt exhibits a type section of the Lower Gondwana rocks. The Bokaro coalfield is one of the three major

coalfields in the Damodar Valley belt besides Raniganj and Jharia and is named after the Bokaro River that meanders through

this coalfield. Geographically, it is divided into West and East Bokaro coalfields.

The West Bokaro Coalfield spreads over an area of about 180 sq km with its northern margin characterized by a boundary fault.

Towards south and west, the Gondwana sediments overlie the Precambrian rocks of Chhotanagpur Gneissic Complex with a

profound unconformity. Talchir, Karharbari, Barakar, Barren Measures, Raniganj, Panchet and Supra Panchet Formations of the

Gondwana Supergroup, each manifesting its characteristic litho-assemblage and depositional environment, are exposed in the

area. A number of near-surface coal seams of non-coking and medium-coking variety are being mined from the coal-bearing

Barakar Formation. Some thin coal seams are present in the Raniganj Formation as well.

Gondwana

10. Jharkhand:Basal Gondwana Glacio-MarineSedimentation in West Bokaro Coalfield

Lamproite dyke in Barren Measures, Chotha NadiStep faults within Barren Measures along Chotha Nadi

Overview

The West Bokaro Coalfield (23º44’-23º50’30”N; 85º24’-85º42’E) is located in the Hazaribagh, Ramgarh and

Bokaro districts of Jharkhand State. Ranchi, the state capital is situated about 70 km towards south of this

area.

IGC

DELHI 2020

55


Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Johna Falls, Rock Gardens, Tagore Hill

Arrival Ranchi by Air

Day 2 Dudhi Nadi section Talchir rocks with glacial/marine imprints

resting over a Precambrian basement.

Features of glacial origin and sedimentary

structures

Day 3 Dumerbera area of West

Bokaro Coalfield and the pronounced unconformity between

them. Coal seams of Barakar

Day 4 Chotha Nadi section

Departure Ranchi

Arrival New Delhi

by air

Basement/Gondwana contact relationship Rajrappa Temple

Contact between coal-bearing Barakars and

overlying argillaceous Barren Measures.

Ultrabasic intrusive rocks


Normal fault observed within Raniganj Formation near Lugu hill

56

Synoptic Geology

The 2000-km-long foreland alluvial plain flanking the Himalaya displays a characteristic transverse drainage system formed by

rivers originating in this mountain belt and flowing in southerly direction. Kosi and Teesta megafans are two huge sediment

bodies associated with this kind of drainage. Teesta megafan lies in the foothills of Darjeeling Himalaya between Mahananda

River in the west and Teesta River in the east with its apex coinciding with the emergence of the river. It covers an area of about

18,000 sq km in India and Bangladesh. Besides these bounding rivers, many other streams flow across the megafan in a radial

pattern.

From north to south in the Sikkim - Darjeeling Himalaya, the Teesta River traverses through a gamut of lithounits belonging to

Gondwana Supergroup (comprising sandstone, carbonaceous shale and

coal), Siwalik Group (comprising alternating sequence of soft sandstone,

siltstone, claystone and pebble beds), Quaternary sediments of

Pleistocene age and unconsolidated gravel, sand-clay of Holocene.

The Main Central Thrust (MCT) crosses upper part of Teesta whereas the

Main Boundary Thrust (MBT) separating the Siwalik Group of rocks from

the overlying Gondwana Group and low-grade metamorphites of Daling-

Buxa Group (slaty quartzite and chloritic phyllite) crosses the lower part

within the mountainous reaches. The Teesta River follows the NW-SE

Teesta lineament in its lower reaches.

Some key sections in the Teesta megafan and few smaller coarse-grained

piedmont deposits occurring in the inter-megafan areas can be examined.

Dynamics of the transverse drainages and sedimentation from these rivers

can be gleaned from selected exposures.

11. Sikkim: Transverse Drainages ofthe Himalayan Foreland Basin TectonicGeomorphology of the Teesta Megafan

–

Sedimentary structures in Baikunthapur

Baikunthapur scarp section, Sevok Khola

Teesta River in mountainous terrain, near Rambi

Overview

Teesta is one of the main Himalayan rivers that flows across Sikkim and West Bengal in Indian Territory and

then joins the Brahmaputra River near Raniganj town in Bangladesh. Originating in the glaciers of northern

Sikkim, it is formed by the confluence of Lachen Chu and Lachung Chu at Chungthang (North Sikkim). After

its journey in the mountainous region through steep, narrow gorges and rapids, it debauches into the plains

near Sevok.

Teesta and Kosi Rivers form spectacular and large megafans in the Himalayan foreland basin.

IGC

DELHI 2020

57


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Bagdogra by air

Departure Bagdogra

Arrival Siliguri/ Kalijhora,

by road

Day 2 Siliguri-Teesta River

(between Gajoldoba and

Domohani-Siliguri)

Teesta river around Manpong, Baikunthapur,

Shaugaon

Day 3 Siliguri-Darjeeling- Tea gardens of Darjeeling

Bagdogra

Day 4 Departure Bagdogra.


Study the rocks of Siwalik and Gondwana Teesta Dam Project, Coronation Bridge

Group and their thrust contact. Coalescing (built in 1930) and Sevokeswari Kali

fans across the Teesta megafan Temple

Scarp sections of terrace, channel Scenic confluence of Teesta and Chel

morphology, depositional processes in the rivers

megafan. Modern depositional pattern of


Lachung, Sikkim

58

Rumtek Monastery, Gangtok

Synoptic Geology

Different geotectonic domains observed in the Sikkim Himalaya include the mollase-type deposits of the Siwaliks (Mio-Pliocene)

forming the southernmost Sub-Himalaya. The Main Boundary Thrust (MBT) separates the Sub-Himalaya from the Lesser

Himalaya in the north. The Lesser Himalaya are represented by Gondwana rocks (Carboniferous- Permian), carbonate rocks

(Buxa Formation) and a thick metasedimentary sequence of dominantly pelites with subordinate psammite and wacke (Daling

Group). Further north, the overlying Higher Himalayan Crystalline sequence has experienced higher grade of

metamorphism and is separated from the Lesser Himalaya by the Main Central Thrust (MCT) that forms an extensive

deformation zone containing the inverted Barrovian sequence.

The Lesser Himalayan belt bounded between the MCT and MBT has experienced multiple phases of thrusting and duplex

formation. The Lesser Himalayan Duplex (LHD) has been recognized in Darjeeling-Sikkim Himalaya and consists of horses

involving Daling, Buxa and Gondwana rocks. The frontal part of the LHD is exposed in the Rangit Window through the overlying

Ramgarh thrust sheet that consists of Proterozoic Daling Group of rocks.

The HHC sequence is overlain by a thick, fossiliferous pile of Tethyan sedimentary sequence (Cambrian to Eocene) separated

by the South Tibetan Detachment System (STDS).

(HHC)

11. Sikkim:Unusual Deformation Kinematics

Stromatolitic limestone, TatapaniFolded Gondwana Group rocks, Rangit Window

Overview

Sikkim Himalaya depicts various geotectonic domains and the thrust systems similar to the other sectors of

Himalaya. Understanding the deformation mechanisms and the origin of inverted metamorphic sequence as

depicted by the presence of higher grade rocks at progressively higher structural levels, are the few most

debated topics in Himalayan geology and may hold the key for better understanding of the tectono-

metamorphic evolution of the Himalayan thrust-fold belt.

IGC

DELHI 2020

59


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Bagdogra by air

Bagdogra to Siliguri

by road

Day 2 Siliguri to Sebok -

Kalikhola Melli -

Jorthang

Day 3 Jorthang - Rishi -

Legship - Sikkip -

Namchi - Phong -

Namthang - Rongpo

Day 4 Rongpo - Rorathang -

Rongli - Aritarn -

Algara - Lava -

Gorubathan -Siliguri

Departure Siliguri

by road. Arrival

Bagdogra Bagdogra

to New Delhi by air

Along the salient in the western extremity of Tea gardens, Mahananda Wildlife

the Darjeeling Lesser Himalaya. The MBT Sanctuary

and the MCT. Sub-Himalayan to Higher

Himalayan sequences

Siliguri - Garidjua -

Dudhia Manjwa - Siliguri

Across the recess up to its middle. Salugara and Kalchakra monasteries.

The MBT and the Rangit Window. Teesta River barrage for bird watching

The Lesser Himalayan Duplex.from Jorthang Darjeeling and Gangtok are hill stations

to north of Rishi Horses of different thrust and picturesque places

sheets involved in duplex formation

Eastern boundary of the recess. The MCT

and the HHC sequence. Contact of

Renok - Gondwana Group and the Quaternary

sediments. The Main Frontal thrust


60

Synoptic Geology

Eastern Ghat Mobile Belt (EGMB) stretches parallel to the eastern coastline of

India for over 1000 km skirting the three major cratonic blocks of Bastar,

Singhbhum and Dharwar. The regional strike of EGMB is NE-SW and major

ductile shear zones parallel to the strike mark its boundaries. It also figures

prominently in the reconstruction of the pre-drift configuration of East Gondwana.

Constituted dominantly by high grade para- and ortho-gneisses with intrusive

massif anorthosite and felspathoidal alkaline plutons, this belt is subdivided

longitudinally on the basis of lithological association into four zones. The northern

part of the EGMB is shown to have a distinctly different thermo-tectonic history

from the southern part leading to its division into a Northern and a Southern

EGMB, separated by the Godavari Rift.

The rocks of EGMB experienced two phases of granulite facies metamorphism

and a third amphibolite facies event. The first metamorphic episode (M ) of

Archaean age was at ultra-high temperature. Thermal reworking during a

subsequent metamorphic event (M2) at ~960 to 1000 Ma led to near isothermal

decompression down to 5-6 k bar. The third metamorphism (M ) is interpreted as

a Pan-African amphibolite facies event with a peak of 600 C at 5 k bar.

1

3

o

12. Odisha:From the Eastern Ghat Mobile Belt to Craton

Rugged outcrops of Chilka lake anothosite

Buddha sculpted in khondalite, Ratnagiri museum

Overview

Odisha state is located along the east coast of India. It is a mineral rich state with large resources of bauxite,

iron ore, coal and chromite. It has a large forest cover and many wild life sanctuaries and has earned a name

for sand sculpting and handicrafts. Known as the largest wintering ground for the migratory birds in India,

Chilka is the world’s second largest brackish water coastal lake located in the state. The capital city of

Bhubaneshwar is known for its temples. The world famous Lord Jagannath temple at Puri is located about 60

km south of Bhubaneshwar.

IGC

DELHI 2020

61


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Bhubaneshwar

by air. Bhubaneshwar-

Lalitgiri-Chandikhole-

Sukinda

Day 2 Sukinda-Duburi-

Tomka-Daitari- Working iron ore mine in BIF, Sukinda

ultramafic complex accounting for major

chromite production in India

Day 3 Angul-Bhubaneshwar High grade gneisses, quartz-garnet-

orthopyroxene-sillimanite

evidences of Archaean

facies metamorphic

Gondwana sediments

Day 4 Departure

Bhubaneshwar Arrival

New Delhi by air

to New Delhi by air

Khondalite – Charnockite assemblage. Udayagiri,Ratnagiri, Lalitgiri hills

Terrane boundary shear zone, ultramylonite- preserve the ruins of the Buddhist

pseudotachylite complex that once flourished in coastal

Odisha

Oldest (3.51 Ga) greenstone sequence.

Angul

Aluminium smelter at Angul.

cordierite- Sight seeing at Bhubaneshwar.

gneisses preserving Handicrafts and feligree work of Odisha

(~3 Ga) granulite

event and cover


62


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Bhubaneshwar

by air. Bhubaneshwar-

Balugaon-Chilka

Day 2 Chilka-Rambha-Puri Khondalite – Charnockite - Calc silicate

association. Partial melting product leptynite Jagannath temple.

Day 3 Puri-Konark-

Bhubaneshwar beaches nearby. Sight seeing at

Bhubaneshwar

Day 4 Departure

Bhubaneshwar. Arrival

New Delhi by air

Incipient charnockitisation, massif Chilka is a large brackish water coastal

anorthosite and its variants lake attracting migratory birds

Puri is famous for the beach and the Lord

Picturesque Konark temple and the


Rock sculpturing in Sun Temple, KonarkView of Lord Jagannath Temple, Puri

IGC

DELHI 2020

63

Flat topped bauxite capping

Synoptic Geology

The East Coast Bauxite deposits are located in the east-central part of the Eastern Ghat and have formed by intense weathering

of the Precambrian high grade metamorphic rocks. The bauxite deposits are blanket type and form capping with areal spread up

to 15 sq km and thickness upto 54 m. In general, these are lateritic bauxite with low silica, titanium and high iron.

The bauxite deposits occur generally on the gentle to moderately sloping plateaux made up of khondalite (quartz-feldspar-

garnet-sillimanite-graphite bearing gneiss). Hills with bauxite duricrust are devoid of vegetation.

These bauxite deposits are gibbsitic in nature and are formed by a gradual alteration of the khondalite to completely kaolinitised

rock or lithomarge and the bauxitic duricrust.

The bauxite deposits of Odisha sector are classified into the Northern, Central and Southern groups. Pachpatmali deposit forms

a part of the Central group and is being exploited since 1985 through a open cast mine of 4.8 tpa capacity.

on the top

12. Odisha: East Coast BauxiteProvince Transformation of High GradeMetamorphic Rocks to Bauxite

–

Profusely Kaolinitised KhondaliteThe bedrock Khondalite

Overview

The East Coast Bauxite Province stretching over to the states of Andhra Pradesh and Odisha constitutes

1650 million tonnes of ore. The bauxite bodies occur scattered over a length of 400 km and a width of 30 km in

an alignment conforming to the NE-SW trend of the Eastern Ghat. Odisha contributes about 60 percent of the

total bauxite production of the country from these deposits.

64

Alumina refinery, Damanjodi, Odisha


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Vishakhapatnam

by air. Vishakhapatnam

-Damanjodi by road

Day 2 Pachpatmali Bauxite

Mine-Damanjodi

alumina refinery

Day 3 Departure

Vishakhapatnam. Arrival

New Delhi by air

In situ transformation of high grade

metapelitic rocks to bauxite. Flat topped

bauxite caps. Visit to alumina refinery


IGC

DELHI 2020

65

Related Information

Pachpatmali is the single largest bauxite deposit in India with a total resource of about 310 million tonnes. The deposit extends in

length for 16 km and attains a maximum width of 2 km. The plateau has elevation of 1180 - 1355 m. The deposit is nearly flat and

blanket type forming over khondalite. Ore on an average contains about 45% alumina and about 25% silica. And is gibbsitic in

nature.

A view of the Pachpatmali Hill

66

Pipe-2 kimberlite, Wajrakarur Kimberlite Field

Synoptic Geology

The southern Indian peninsular shield comprises the Dharwar craton in the north and the Southern Granulite Terrane in the

south. The Dharwar craton is a typical Archaean granite-greenstone terrane with a gneissic basement of tonalite-trondhjemite-

granodiorite (TTG) composition. It is divided into Eastern Dharwar Craton (EDC) and Western Dharwar Craton (WDC).

Kimberlites discovered in southern India till now are restricted to the EDC and are distributed in four fields including Wajrakarur

Kimberlite Field (WKF). In addition, there are two lamproite fields in the EDC.

The Wajrakarur Kimberlite Field measures ~120 km x 60 km and is located close to the western margin of the Cuddapah Basin.

The area exposes the metamorphosed volcano-sedimentary sequence of the Ramagiri- Penakacherla schist belt surrounded

by gneisses (Peninsular Gneissic Complex), which are intruded by late to post-kinematic granitoids (Closepet Granite and its

equivalents). Quartzo-feldspathic veins and pegmatites intrude these granites and schist belt units. Predominantly NW-SE and

ENE-WSW trending dolerite, gabbro and lamprophyre dykes constitute younger mafic intrusive bodies. The dominant control for

kimberlite emplacement in this field is provided by the intersection of the major lineament trending ENE-WSW with the other one

trending NW-SE.

13. Andhra Pradesh:Wajrakarur Kimberlite Field,Eastern Dharwar Craton

Mantle xenoliths from kimberlites of Wajrakarur Kimberlite Field

Overview

Over 100 kimberlite intrusions are known in the Dharwar craton spread over the states of Andhra Pradesh

and Karnataka. This area witnessed intense diamond mining activity during 13th-18th centuries AD.

Considered as the land of first diamond finds in the world, both primary and secondary type deposits are

found here. The Krishna Valley from this part of India is known to have produced some of the most celebrated

diamonds including the Koh-i-Noor, the Great Moghul and the Orloff.

IGC

DELHI 2020

67

Serpentinised olivine macrocryst in Chigicherla kimberlite, Wajrakarur Kimberlite Field.


Starts: New Delhi

Finishes: Bengaluru

Trip Description

Day 1 Departure New Delhi. Famous gardens of Bengaluru

Arrival Bengaluru by air

Day 2 Bengaluru-Lepakshi- Chigicherla Kimberlite (pipes 1, 4 & 5)

Chigicherla- Anantapur

Day 3 Anantapur-Kalyandurg-

Muligiripalle- Lattavaram

- Wajrakarur-Bengaluru

Temple architecture (14th-16th Century

AD) at Lepakshi

Examination of Kimberlite pipe KL – 2 at Kimberlite park and museum at

Kalyandurg, Pipe-5 at Muligiripalle Wajrakarur

and Pipes-3 & 4 at Lattavaram

Day 4 Departure Bengaluru for

respective destinations

or New Delhi by air


68

Synoptic Geology

The Dharwar craton of southern India exposes a wide segment of continental crust with a geological record since Early to Late

Archaean. The three major components of the craton as described above are distributed into Western and Eastern Dharwar

Craton. The two cratonic blocks with contrasting crustal accretionary histories and variably thickened crustal segments are

juxtaposed along a regional lineament.

The crustal growth in the Dharwar Craton and in the granulite terrain extending upto PCSZ was accomplished during the period

from 3400 Ma to 2500 Ma with significant accretion during Late Archaean. The granulite facies metamorphism in these domains

is dated ~2600 Ma and the preservation of such biotite (Rb-Sr) ages in these rocks indicates that the craton has remained stable

since 2500 Ma.

The craton also hosts gold, iron, manganese, chromium, PGE and copper deposits. Uniformitarian models invoking lateral

accretion of juvenile crust in the arc environment or non-uniformitarian subduction models involving plume or combine plume-

arc settings are proposed for the present configuration of the craton.

14. Karnataka:Archean Granite-Greenstone Terrane, Dharwar Craton

Royal Palace at Mysore

Spinifix-textured komatiites Pillowed metabasalts at Maradihalli

Overview

The Dharwar craton is made up of Tonalite-Trondhjemite-Granodiorite(TTG) gneisses (Peninsular

Gneisses) with linear schist belts represented by thick volcano-sedimentary sequences (Dharwar

greenstones) and the younger post-kinematic granodiorite / granite plutons. The above litho-assemblages

show greenschist to middle amphibolite facies metamorphism and extend upto the Fermor Line. The terrain

south of the Fermor Line is dominated with granulite facies rocks including charnockite, pyroxene granulite,

banded magnetite quartzite association upto Palghat-Cauvery shear zone (PCSZ), and show retrogression

to epidote-amphibolite facies in structurally weak zones marked by shears.

IGC

DELHI 2020

69

Trip Plan 14a: 4 Days 3 Nights

Starts: New Delhi

Finishes: Bengaluru

Trip Description


Arrival Bengaluru by air plutonic dykes, magma mixing, mingling and

related features. Kolar Schist Belt

Day 2 Mysore-Sargur-Mysore Ancient supracrustals (>3.0 Ga) and younger

granite pluton (~800Ma) Brindavan Gardens.

Day 3 Mysore-Bellur-Hassan Study of spinifex-textured komatiites, pillowed

basalts, chromite mines and basement-cover

relationships (greenstone-gneiss-granite

contact zones)

Day 4 Departure Hassan. Bengaluru sightseeing

Arrival Bengaluru.

Departure for respective

destinations or New

Delhi by air

Granite-gneiss quarries to observe syn- Visit to Kolar Gold Mines

Bengaluru-Kolar -

Bengaluru

Mysore sightseeing including the famous

Visit to Gomateshwara Temple at

Sravanabelagola and to Belur and

Halebid Temples


70

Trip Plan 14b: 4 Days 3 Nights

Starts: New Delhi

Finishes: Bengaluru

Trip Description

Day 1 Departure New Delhi. Sight seeing at Bengaluru

Arrival Bengaluru by

air. Bengaluru-Hassan

Day 2 Hassan-Gorur and

Hassan-Belur Dharwar Craton dated at 3360 Ma.Sargur

metasediments

Day 3 Chikmagalur-Mulaingiri Kartikere Conglomerate that forms base of

the Bababudan Group. Thick pile of

amygdular mafic lava flows and Banded Iron

Formation

Day 4 Chitradurga-Sira -

Bengaluru. Departure

for respective

destinations or New

Delhi by air

The oldest TTG-Peninsular gneiss suite of Gometeshwara temple, Sravanabelagola.

Belur and Halebid temples

Scenic spots of Mulaingiri Hills

Ingaldhalu Copper Mines. Chitradurga

Volcanics and associated sediments

including pillowed metabasalts at Maradihalli.

Study of gold bearing BIF of Ajjanhalli


Feet of 17.38 m high Gomateshwara statue at Sravanabelagola

IGC

DELHI 2020

71

Stone carving in Badami caves

Synoptic Geology

The Proterozoic intracratonic Kaladgi Basin extends in an east-west tract over the northern part of theArchaean Dharwar craton,

southern India. It exposes about 5 km thick sedimentary pile and is spread over an area of 8300 km . It is divided into a lower,

deformed Bagalkot Group and an upper, flat-lying Badami Group. The basin consists of three quartzite shale carbonate cycles.

Well-preserved geological features illustrating typical Proterozoic sedimentation and basin tectonics including basin margin fan

deposits, syntectonic brecciation, seismite, stromatolite and penecontemporaneous deformation structures, the dome and

basin pattern of deformation in the lower Bagalkot Group, major unconformities

bounding the sequences and basinal scale faults can be seen in a typical

intracratonic basin setting.

The limestone resources in both the Kaladgi and Bhima Basins and the recent

discoveries of radioactive minerals provide an extra dimension for the study.

Presence of late Precambrian biota in these basins has opened up a new vista for

further research on the Cambrian explosion of biotic life.

2

14. Karnataka: The Proterozoic KaladgiBhima Basin: Sedimentation, Tectonicsand Uranium Mineralization

–

Stone carving in Badami caves

Overview

Two major basins (Cuddapah and Vindhyan) and five smaller basins (Chattisgarh, Pranhita-Godavari,

lndravati, Bhima and Kaladgi) constitute the Purana basins and represent a unique feature of the Proterozoic

geology of the Peninsular Indian Shield. Initiated during Late Palaeoproterozoic and continued episodically

as active depocentres till the end of the Neoproterozoic times, each of these basins is unique with

characteristic tectono-stratigraphy. Their gross features, including the recurrent orthoquartzite-carbonate-

shale association, paucity of igneous rocks, lack of pervasive metamorphism and structural configuration

suggests that these seven Proterozoic basins are analogous to the present day "Atlantic-type" passive

continental margin systems, which develop under extensional tectonic regimes on the trailing edges of

continental blocks. However, the crystalline continental crustal rocks flooring these basins as basement and

also their provenance, is what makes these seven supracrustal basins different from the typical passive

continental margin systems. Besides their significance in unraveling the Proterozoic supracrustal history of

the Indian Peninsular Shield, these basins contain economic mineral deposits.

72

Trip Plan 14c: 4 Days 3 Nights

Starts: New Delhi

Finishes: Bengaluru

Trip Description

Day 1 Departure New Delhi. Travel to Bagalkote by night train Sightseeing at Bengaluru


Departure Bengaluru for

Bagalkote

Day 2 Arrival Bagalkote.

Bagalkote-Badami Gaddankeri limestone mines

Day 3 Badami - different Type

sections Cholachaguda, Mahakut, B.N.Jalihal,

Konkankoppa, Niralkere Railway cutting.

Travel to Bengaluru by night train

Day 4 Departure Bengaluru for


or New Delhi by air

Type sections of Bagalkot Group in Sightseeing around Bagalkote

Study of type sections at Chiknasbi- Badami caves I Natural Arch – National

Monuments and Heritage sites


1

2

3

4

5

6

7

8

9

10

Geological map of Badami-Gulbarga area (Raghunandan and Vidyadharan, 1993) Explanation of numbers in index: I

1. Deccan Trap; 2. Kaladgi Supergroup; 3. Badami Group; 4. Closepet and related granites; 5. Chitradurga Group

and equivalent; 6. Bababudan Group and equivalent; 7. Early Archean Granitoids; 8. Hutti Group; 9. Sargur Group,

and 10. Peninsular Gneisses.

IGC

DELHI 2020

73

Trip Plan 14d: 4 Days 3 Nights

Starts: New Delhi

Finishes: Hyderabad

Trip Description

Day 1 Departure New Delhi. Sightseeing at Hyderabad

Arrival Hyderabad.

Departure Hyderabad

Arrival Gulbarga by

road

Day 2 Almatti - Muddebihal

and Talikota - Hunasgi

Shahapura Muddebihal, Tirth - Talikota, Ukinal

Day 3 Shahapura - Gogi - Gogi Uranium Deposit. Shahapur Cement Visit to World Heritage sites at Gulbarga

Gulburga - Hyderabad

Day 4 Departure Hyderabad for


or New Delhi by air

Study of type sections at Almati Railway Visit Almatti Dam site

- cutting, Almatti - Muddebihal Traverse,

Plant


74

Synoptic Geology

The Dharwar Craton in southern India exposes a wide segment of continental crust with a geological record since Early

Archaean (3.6 Ga) to Late Archaean (2.5 Ga). Three major components in the craton are, (i) extensive tonalite-trondjhemite-

granodiorite (TTG) suites, granite-gneiss associations (Peninsular Gneisses); (ii) thick volcanic-sedimentary basins

(greenstone belts), and (iii) voluminous younger granitoids. These three components are distributed in two major cratonic blocks

named as the Western Dharwar Craton (WDC) and Eastern Dharwar Craton (EDC). The two cratonic blocks with contrasting

crustal accretionary histories are juxtaposed along a regional lineament. Significant gold mineralization in the Dharwar Craton is

associated with a major event of accretion of volcano-sedimentary basins. The auriferous schist belts of Kolar, Hutti, Ramagiri,

Jonnagiri, Gadwal, Raichur, Kushtagi-Hungund and Sandur form part of the EDC.

Gold mineralization in the Dharwar greenstone belts is structurally controlled, epigenetic, ‘orogenic’ or ‘lode gold’ style, most

commonly associated with quartz ± carbonate veining and sulphidation of high-strain-zones or certain lithounits such as Banded

Iron Formation (BIF) or carbonaceous phyllite. Gold mineralization in the Drarwar Craton is placed at ~2500 Ma and is relatable

to the timing of emplacement of voluminous granitoids in the EDC.

14. Karnataka:Selected Gold Prospects

Stone Chariot at Humpi, Karnataka

Banded Iron Formation (BIF) with carbonate layers

and tensional gash veins of quartz, Chitradurga

Massive carbonate associated with BIF

showing quartz veins of variable dimensions, Chitradurga

Overview

Over 100 occurrences, prospects and deposits of gold are distributed in the Neoarchaean greenstone belts

of Dharwar Craton in states of Karnataka, Andhra Pradesh, Goa, Tamil Nadu and Kerala. Amongst them,

there are about 25 deposits with a total gold endowment (gold produced if any plus existing drilled resources)

in the range of 0.5 to 1 tonne, about 20 deposits in the range of 1 to 6 tonnes of gold and only two major

deposits, Kolar and Hutti, with a total endowment in excess of 100 tonnes. The Kolar Gold Field has produced

about 800 tonnes of gold in its mining history.

IGC

DELHI 2020

75

Trip Plan 14e: 4 Days 3 Nights

Starts: New Delhi

Finishes: Bengaluru

Trip Description



Bengaluru - Kolar-

Bengaluru

Day 2 Bengaluru - Bellara -

Chitradurga areas of Chitradurga schist belt

Day 3 Chitradurga-Ganajuru- Gold mineralization at different locations in World Heritage Centre at Humpi

Gadag - Bengaluru

Day 4 Departure Bengaluru.

Arrival New Delhi or to


by air

Granite-gneiss quarries to study syn-plutonic Sight seeing at Bengaluru

dykes, magma mixing and mingling and

related features. The Kolar Schist Belt

Sulphide hosted gold mineralization in Chitradurga Fort

different

Gadag Schist Belt


Native gold in arsenopyrite, Kolar Schist Belt Occluded grains of native gold

in arsenopyrite, Nundydroog Mine, Kolar Schist Belt

76

Trip Plan 14f: 4 Days 3 Nights

Starts: New Delhi

Finishes: Bengaluru

Trip Description

Day 1 Departure New Delhi. Chitradurga Fort

Arrival Bengaluru

Bengaluru -

Chitradurga

Day 2 Chitradurga -

Penchcherla - Jonnagiri -

Hutti.

Hirenagnur Jonnagiri prospects

Day 3 Hutti - Study of gold mineralization in Gadag

schist belt

Day 4 Departure to respective


by air

Sulphide hosted gold mineralization in

different areas of Chitradurga schist belt

by air.

Bellara -

With metabasalt hosted gold deposit, Hutti is

the only gold producing mine in India. Gold

mineralization at Uti, Hira-Buddini and

Gadag - Bengaluru

Sight seeing at Bengaluru


IGC

DELHI 2020

77

Geological Map of Southern Peninsular Shield

Synoptic Geology

Region located to the south of orthopyroxene isograd and indicative of granulite facies metamorphism is generally known as the

Southern Indian Granulite Terrain. It has two components - a Northern Granulite Terrain (NGT), forming the root zone of Dharwar

Craton and Southern Granulite Terrain (SGT), occurring as a Proterozoic mobile belt. Three prominent ductile shear zones of

cratonic extent dissect the SGT. These are Moyar Bhavani - Attur shear zone (MBASZ) in the north, Palghat-Cauvery shear

zone (PCSZ) in the middle and Achankovil shear zone (AKSZ) in the south. The PCSZ marks a major terrain boundary that

separates theArchaean Dharwar Craton in the north from the Pandyan mobile belt in the south.

The Nd-model ages for the granulites exposed in this mobile belt are in the range of 2.7 to 1.3 Ga indicating that major part of the

crust south of PCSZ was formed during Palaeoproterozoic. The Pandyan Mobile Belt is divisible into a northern Madurai and the

southern Trivandrum Blocks with the AKSZ demarcating the boundary. The Madurai Block comprises dominantly of

metasedimentary swathes (quartzite-pelite-carbonate assemblage) occurring as interbands within the charnockite and

retrograded gneisses.

Trivandrum Block, lying south of the AKSZ, constitutes the southernmost segment of this granulite belt. It is characterized by

extensive Khondalite suite represented by garnet-sillimanite-graphite-cordierite bearing para-gneisses, calc-silicate rock and

quartzite. The Nagercoil charnockite massif occurring at the southern part of this block is considered to represent a C-type

magma emplaced during Neoproterozoic.

15. Tamil Nadu and Kerala:From the Root of an Archaean Craton to aPan-African Granulite Terrane

Alternating sequence of pink marble andgarnet-biotite gneiss in Satyamangalam Group

Calc granulite, Madukkarai

Overview

The Southern Indian Peninsular Shield (SIPS) exposes Precambrian crust showing complex structural and

metamorphic history. Fermor (1936) divided the SIPS into a charnockite terrain in the south and east and a

non-charnockite terrain in the north. The boundary between these two terrains, known as 'Fermor Line', was

considered to represent a fundamental litho-tectonic boundary. Subsequent studies along the Fermor Line

revealed that the charnockite suite occurring south of the Fermor Line had formed by regional granulite facies

metamorphism of a variety of precursor lithounits (TTG gneisses and the associated supracrustal rocks),

which commonly occur in the north.

78

Trip Plan 15a: 5 Days 4 Nights

Starts: New Delhi

Finishes: New Delhi

Trip Description

Day 1 Departure New Delhi Sight seeing at Bengaluru


Bengaluru - Kabbaldurga (incipient charnockitization)

Day 2 Bengaluru - Kishengiri - Peninsular Gneiss, contact between granulite

and amphibolite gneiss. Sittampundi layered

anorthosite

Day 3 Salem - Bhavani -

Mettupalayam Satyamangalam Group, enderbitic

Bhavani ultramafic-gabbro-

layered complex

Day 4 Mettupalayam -

Chennimalai Devattur

Oddanchattram

Puduchchattiram

Kodaikanal

Day 5 Kodaikanal - Madurai

by road. Madurai -

New Delhi by air

Kabbaldurga quarry that shows transition of

2.6-Ga granite gneiss into the charnockite

Salem

Bhavani gneiss, ancient supracrustal rocks

of

granulite,

anorthosite

Charnockite and gneiss exhibiting Kodaikanal, the pilgrim town of Palani

extensional shear band structure, the

Oddanchattram Anorthosite body


IGC

DELHI 2020

79

Trip Plan 15b: 4 Days 3 Nights

Starts: New Delhi

Finishes: Thiruvananthapuram

Trip Description


Arrival

Thiruvananthapuram

by air. Departure

Thiruvananthapuram.

Arrival Rajapalaiyam

by road

Day 2 Rajapalaiyam -

Ambasamudram -

Kottavattam -

Potancode -

Thiruvananthapuram Achankovil shear zone. Incipient

charnockitization

Day 3 Thiruvananthapuram -

Malyankil -

Thiruvananthapuram Kerala Khondalite Belt (KKB). At Malyankil,

various lithounits of the KKB including types

of granulite and patchy charnockite

Day 4 Departure

Thiruvananthapuram

for respective

destinations or New

Delhi by air

Sheared gneissic granite, flanked by granitic

cordierite gneiss, bands of calc-silicate rocks

and marble. Pelitic gneiss showing

dehydration melting. Deformation near

Quarry faces to study gneiss-charnockite- Sight seeing at Thiruvananthapuram

mafic granulite complex relationships in the and neighbouring region


80

Parallel laminated tuff, the product ofash-surge deposit of prehistoric eruption

Synoptic Geology

The Andaman-Nicobar Islands form a part of the arcuate island-arc chain extending from Myanmar to Indonesia. An active zone

of subduction along the Andaman-Java trench lies to the west of the Andaman-Nicobar Islands. Underthrusting of the Indian

oceanic plate below the Eurasian Plate along this subduction zone since Cretaceous has resulted in the formation of an

accretionary prism and a high forearc-outerarc ridge known as theAndaman-Nicobar ridge.

The Outerarc is represented by tectonic slices of Cretaceous ophiolite and Eocene sediments (Mithakhari Group) in small

isolated basins constituting accretionary prism. Forearc products include siliciclastic Oligocene turbidite (Andaman Flysch

Group) and Mio-Pliocene carbonate turbidite (Archipelago Group). Inner arc volcanics are well marked in Quaternary volcanism

of Barren and Narcondum Islands that are located about 100 km northeast and north of Port Blair.

Barren is the only active volcano in the Indian subcontinent and along with dormant Narcondam volcano it is the product of an

oblique subduction between India and SE Asian plate in the Burma-Java subduction complex. About sixty potentially active

volcanoes including Barren Volcano lie along this SEAsian volcanic rim.

16. The Andaman-Nicobar Islands:Anatomy of an Accretionary Prism

Chiriatapu

Sandstone, siltstone and shale bearing Andaman Flysch sequence

Overview

The Andaman-Nicobar Islands (area 8249 km ) constitute the southernmost part of the Indian subcontinent

and are designated as a Union Territory of India with Port Blair city as capital. Constituted by a group of 572

islands in the Bay of Bengal, only 38 of these are inhabited. These islands possess a unique tropical

rainforest cover hosting a plethora of wildlife including several endemic varieties. Known for the picturesque

beaches and shell wealth, theAndaman-Nicobar Islands also house the most spectacular butterfly species in

the world. On 26th December 2004, these islands were struck with a devastating tsunami caused by a major

earthquake in the Indian Ocean.

2

IGC

DELHI 2020

81


Starts: New Delhi

Finishes: New Delhi

Trip Description


Arrival Port Blair via

Kolkata

Day 2 Port Blair-Corbyn’s

Cove-Kodiaghat-

Port Blair ultramafic cumulate sequence of the ophiolite

suite

Day 3 Port Blair-Chiriatapu-

Munda Pahar - Port

Departure for

y ship the Munda Pahar provide a fabulous view

of isolated islands, submerged corals and

the breath-taking sunset. Sea voyage

Day 4 Barren Island - Port Visit to Barren Island. Observe the volcanic Sea voyage

Blair

Museums and shopping places with

ethnic products

Observe the pillow basalt, andesitic lava, Corbyn’s Cove has one of the most

plagiogranite-diorite suite of rocks and the picturesque sea-beaches

Examine the ocean pelagic sediments (OPS) Chiriatapu is located at the southern tip

and pyroclastic andesite of South Andaman. The lush green

Blair. mangroves, forest cover with birds and

Barren Island b

sequence

Day 5 Departure Port Blair.

Arrival New Delhi


82

Related Information

The Andaman ophiolite occurs in the outer-arc of the active Andaman-Java subduction zone, and a dismembered ophiolite

sequence (mantle-cumulates-lavas) is preserved in different thrust slices. Cretaceous-Paleocene radiolarian chert interlayered

with pillow basalt provide an upper age limit of the Andaman ophiolite. The Andaman Flysch Group, occurring in faulted contact

with the ophiolite, represents a thick pile (~3 km ) of turbidite sediments of Upper Eocene to Oligocene age. The Miocene-

Pliocene Archipelago Group, which is not in direct contact with any of the ophiolite slices, consists of subaqueous pyroclastic

rocks and siliciclastic turbidites in the lower part and carbonate turbidites in the upper part.

The Andaman ophiolite consists of a plutonic complex, a volcanic sequence and pelagic sedimentary rocks. Continuous

ophiolite sections are rare due to a thick weathering profile, tropical forest cover and pervasive E-W and N-S fault systems. The

lower part (80% of the total ophiolite outcrop) comprises foliated and highly serpentinised peridotite. The upper part consists of a

layered sequence of ultramafic-mafic rocks, an intrusive section of homogenous gabbro-plagiogranite-diorite-dolerite and an

extrusive section of boninite and tholeiitic basalt lavas. The layered ultramafic-mafic rocks have limited exposures in South

Andaman and Rutland Island. The boundary between the residual peridotite (tectonite represented by serpentinised lherzolite

and harzburgite, which locally contain 2 cm to 4 m long sub-concordant lenses and pods of serpentinised dunite) and the layered

sequence is generally poorly defined, except a sharp contact in the Kodiaghat road section of SouthAndaman.

Geological map of Barren Island Barren Island is still active in the form

of mild explosive (Strombolian) type.

IGC

DELHI 2020

83

Synoptic Geology

The geological evolution of Bangladesh is related to the uplift of the Himalaya and building of deltaic landmass by major river

systems. The geology of Bangladesh broadly comprises two major units, the Precambrian platform in the northwest and

geosynclinal basin in the southeast. The third unit is a narrow northeast-southwest trending zone called the Hinge Zone, which

separates the above two units. The stable Precambrian platform has a moderate thickness of sedimentary rocks above a

Precambrian igneous and metamorphic basement.

The Bengal delta is one of the larger deltas in the world, characterized by rapid

subsidence and filling of a basin. Thick deltaic sediments were deposited as a

megadelta that progressed towards the south. The geosynclinal basin in the

southeast is characterized by ~ 20 km of clastic sedimentary rocks, (sandstone

and shale) of Tertiary age. Only the eastern part of Bangladesh has been uplifted

into hilly landform that merges into the frontal belt of the Indo-Burman ranges to

the east.

Excursions in Co-Host Countries

17 Bangladesh

Geological map of Bangladesh

Trip Plan No. 17 a

The Sundarbans

In the southwestern part of Bangladesh lies the Sundarbans, the home of the mighty Royal Bengal Tiger.Along the coastal parts

of Ganges Delta it is a cluster of islands with an approximate area of 3600 sq km forming the largest block of littoral forests

decorated with diversified assemblage of flora and fauna. This mangrove forest is shared between the two neighbouring

countries, viz. Bangladesh (62%) and India (38%). The physiography is dominated by deltaic formations include innumerable

drainage lines associated with surficial and sub-aqueous levees, splays and tidal flats. There are also marginal marshes above

mean tide level, tidal sandbars and proto-delta clays and silt sediments. Land elevation of the Sundarbans ranges from 0.9m to

2.11m above mean sea level. Geological exploration reveals that the Sundarbans has been evolved through natural deposition

of upstream sediments accompanied by intertidal segregation during Late Quaternary Period.

84

Trip Plan No. 17 b

St. Martin's Island

It is an isolated small offshore island about 9 km south from the tip of the Cox's Bazar-Teknaf

peninsula at the mouth of the Naf River. It is the only coral island in Bangladesh, aligned in NNW to

SSE direction. It is almost flat and about 3.6 m above the mean sea level. There are three islets

joined together at low tide by sandy necks to form a solitary island. The northern and central islets

are known as Jinjira and Dakshinpara respectively, separated by a narrow waist. The southernmost

islet, Cheradia Island, becomes separated during high tide from the central islet. The oldest rock

exposed in St. Martin's Island is a gently dipping shale formation with interbeds of calcareous sandstone and conglomerate of

Upper to Middle Miocene. The shale is overlain unconformably by horizontal shelly and coralline limestone probably of

Pleistocene age.

Trip Plan No. 17 c

Cox's Bazar-Teknaf Coast

The Cox's Bazar-Teknaf coastal plain is a uniform and nearly leveled tidal plain backed by

steep cliffs of dissected Tertiary hills with an average elevation of 150 m. This area is very

attractive for its geomorphic setting, diversified ethnic groups with colourful cultures and

challenging occupations. The world’s longest unbroken sandy sea beach, about 125 km

long with a gentle slope, it stretches all through this coast. Width of the beach

varies slightly from place to place. Besides these attractive

features, numerous paleo-beaches, tidal deposits, lagoonal deposits along with

piedmont deposits enriched the beauty of this coastal plain. The present coastal features

are the result of interactive marine processes since Mid-Holocene transgression in the Bengal Basin.

is about

152m at Cox's Bazar and

Trip Plan No. 17 d

Dauki Fault

The Bengal Basin is bordered on the north by the Precambrian Shillong Plateau, criss-

crossed by fractures resulting from extensive compressional forces, mainly in N-S and E-

W directions as a result of collision of the Indian plate with the Eurasian and Burmese

plates respectively. This type of plate tectonism has given rise to the well-known E-W

trending Dauki Fault, stretching along the common boundary of Bangladesh and

Meghalaya (India). Seismicity of the Shillong Plateau is quite scattered all over the area. The sharp linear topographic feature

often mapped as the Dauki Fault, which is virtually a contact between competent Eocene limestone and much less competent

younger clastic units. Historical records prove that this fault zone was the source of many well-known earthquakes, e.g., the

Great Indian Earthquake of 1897.

IGC

DELHI 2020

85

Synoptic Geology

The Nepal Himalaya has distinct thrust bound lithotectonic units including Tarai - the Piedmont plains (~600 m thick), Quaternary

alluvium underlain by Mid to Late Tertiary Siwalik sediments is tectonically overlain by the Lesser Himalaya (LH) along the Main

Boundary Thrust (MBT). LH is overlain by low to medium grade metamorphites of Lesser Himalayan crystallines. The terrain is

highly deformed with well developed fold-thrust systems. LH is overlain by the high-grade (Ky-grade) metamorphites of Higher

Himalayan Crystallines (HHC) along the Main Central Thrust (MCT). HHC is a ~10 km thick succession of the crystalline rocks

between the MCT and Tethys Himalaya and comprises kyanite- to sillimanite-grade inverted metamorphosed gneisses intruded

by High Himalayan leucogranites. HHC is tectonically separated from the Tethyan sediments by the South Tibetan Detachment

System (STDS).

18 Nepal

Trip Plan No. 18 a

Kathmandu-Sabrubensi-Langtang

This excursion will cover the Lesser and the Greater Himalayan terrains across the MCT.

This excursion is in central Nepal.

Trip Plan No. 18 b

Kathmandu-Kodai-Kathmandu

The excursion is by bus in central Nepal and will cover the Lesser and the Greater

Himalayan terrains along the Kathmandu-Lhasa road.

Geological map of Nepal

86

Synoptic Geology

Sri Lanka is a Precambrian craton that comprises two billion year old metamorphic rocks. The high-grade rocks of Sri Lanka can

be divided into three crustal units, viz., the Highland Complex (HC), the Wanni Complex (WC), and the Vijayan Complex (VC).

Recent age and isotopic data suggest that the high-grade basement rocks of Sri Lanka are more closely associated with the

southeastern part of Madagascar than with theArchaean granulites of southern and eastern parts of India.

The island contains relatively limited sedimentary strata surrounding its ancient hills. Aside from recent deposits along river

valleys, only two small belts of Jurassic (140 to 190 Ma old) sediment occur in Puttalam district, while a more extensive belt of

Miocene limestone is found along the northwest coast, overlain in many areas by Pleistocene deposits. The coastal region of Sri

Lanka has extensive deposits of Teri sands.

19 Sri Lanka

Trip Plan No. 19 a

Batticaloa – Kandy

The traverse would go across the high grade terrane of Sri Lanka and familiarize the participants with the rocks of the Highland

Complex, the Wanni Complex and the Vijayan Complex.

Trip Plan No. 19 b

Colombo - Ratnapura - Galle

Another excursion in high grade metamorphic region of Sri Lanka.

Geological map of Sri Lanka

IGC

DELHI 2020

87

Note

88

Note

Exfoliated Deccan Trap Basalt,Ratnagiri, Maharashtra

Boudinaged and detached quartz veins in highgrade rocks of Almora Nappe, Gairsain, Garhwal

Trachyte with long plagioclase laths, Tsoltak, Ladakh

Clay mottles formed due to extreme weathering ofDeccan Trap basalt, Vijaydurg, Maharashtra

Coquinoidal limestone of Subathu Group,Dharampur, Himachal Pradesh.

Director General,

Geological Survey of India,

27, Jawaharlal Nehru Road,

Kolkata-700016 (India)

Ph: +91 33 22861661/76

E-mail: [email protected]

http://www.portal.gsi.gov.in

2012

View of snow clad peaks of Ladakh batholith

from Khardungla, Ladakh

Sculptured sandstone of Middle Siwalik Group,Panchkula, Haryana

View of the Tehri reservoir area,Tehri, Uttarakhand

Sand dunes near Hunder, Nubra Valley, Ladakh

excursion guide

Documents