hazara field excursion

63
ABSTRACT A four day field trip was arranged by Earth & Environmental Sciences Department of Bahria University, Islamabad to Hazara Basin which extended from 22nd of April 2011 to 25th of April 2011. Field trip was arranged to conduct mapping and to study the rocks of southern Hazara, which range in age from Pre-Cambrian to Miocene. 1

Upload: jabir-jammy

Post on 18-Nov-2015

18 views

Category:

Documents


1 download

DESCRIPTION

A field excursion made to Hazara region by Bahria University Students ....Author: Jabir Jammy

TRANSCRIPT

ABSTRACT

A four day field trip was arranged by Earth & Environmental Sciences Department of Bahria University, Islamabad to Hazara Basin which extended from 22nd of April 2011 to 25th of April 2011. Field trip was arranged to conduct mapping and to study the rocks of southern Hazara, which range in age from Pre-Cambrian to Miocene.

ACKNOWLEDGEMENT

It is great satisfaction and we are grateful to Allah almighty who is always with us and gave us the courage to complete this fieldwork successfully. We are extremely thankful to our Holy Prophet Muhammad (S. A. W), for being a perpetual source of guidance for us in all aspects of life. We are grateful to our teachers Prof. Dr. Sajjad Khan, Mr. Anwar Qadir and Mr. Hammad Ghani (Lec. Department of earth and environmental sciences Bahria university Islamabad) who were very kind and helpful to us at every moment of our field work. Through their guidance and kind advice we have completed this task successfully.We are thankful to Prof. Dr.zafar, head of Department of earth and environmental sciences of Bahria University for providing us the transport facility for our field work.

CHAPTER 1:1.1) INTRODUCTION: The field trip was a four day field excursion to the Hazara basin in vicinity of Abottabad approximately 130 km away from Islamabad. We left for the trip at 09.30am from university on 22nd April 2011 and came back at 7.00pm on 25th of April 2011. The areas which are under study are mainly consists of Jabri area, Nathia Gali and Balakot Fault Region of the Hazara district.1.2) PROCEDURE USED: We applied different procedures in the field which are as follows:

a) Brunton compass was used for measuring dip and strike of rocks and bearing of different formations in the field.b) Dilute HCL was used to differentiate between dolomite and limestone as limestone fizzes on applying HCL.c) Geological hammer was used for collecting samples of different rocks.d) Hand lens was used for studying fossils present in various rocks.e) Global positioning system (GPS) was used to find the location of the area (latitude, longitude and elevation).f) Measuring tape to measure bed thickness.

1.3) OBJECTIVE: The field trip was held in order to observe practically, theoretical work which we have studied so far in our course subjects to get familiar with different lithologies of different formations and sedimentary structures, how to take bearing and make cross section of the exposed strata.

1.4) PREVIOUS WORK: The first publication of any significance on the geology of Hazara is ALBERT VERCHERES paper read before Asiatic Society in 1866. This gives a brief outline of the north eastern end of the Sirban Mountain near Abbottabad. He recognized Carboniferous limestone resting upon volcanic rocks the beds above these he referred in a general way to the Jurassic Formation and the highest strata to the Nummulitic Limestone.WAGGEN AND WAYNE in 1872 put an order for the first time to the structurally complex rocks of monotonous similarity. They also produced a map of the Sirban Mountain, on a scale of one inch to a mile covering an area of 20 square miles. They suggested the presence of rocks from Triassic to Eocene based on fossil evidence and found similarities of some with those from the Cambrian of the Salt Range. This information coupled with series of Papers during the late seventies of the last century, is still considered the soundest basis of rock classification in the area. MIDDLEMISS, 1896, pieced together all the available information, published or unpublished, from all over Hazara on a scale of inch to a mile, together with a detailed account of geology. The present study was initially suggested, in 1956, by N.R. Martin, then a UNESCO advisor and Head of the Geology Department, University of the Punjab, Lahore. A few roadside reconnaissance trips were made by the author in his company during the summer months of 1956, followed by a few independent trips in 1957. Following the footsteps of ALBERT VERCHERE, the Sirban Mountain was selected as a starting point, and a beginning was made in July, 1959. The main purpose of the study was to:a)Revise the stratigraphy.b)Bring the unit names in line with modern stratigraphic nomenclature. c)Produce a new geological map, on a scale of one inch to a mile. Through some short publications to advance the knowledge of geology of Hazara have recently appeared from Lahore, this is the first of its kind since 1896, in which;a)An attempt has been made to bring the rock units in order, to suit the requirements of the stratigraphic nomenclature.b)Revise the ages of units based on faunal assemblages. c)Correlate the units with the adjoining areas. d)Produce a new map of the south eastern Hazara, on a scale of one inch to one mile. Publication of this map with short account of the stratigraphy marks the centenary of the first investigations started in the area by ALBERT VERCHERE, in 1986.

1.5) POPULATION: The population of the Hazara region was estimated to be over 881,000 in 2008. The total area of Hazara is 969km2(760.2sqmi): See table below.

DistrictArea (km)Population(Millions)

Abbottabad18022

Batagram13101.5

Haripur17631

Kohistan75810.8

Mansehra59572.4

Table1: population and area of Hazara District.

1.6) GEOGRAPHY: Hazara is bounded on the north and east by theNorthern AreasandAzad Kashmir. To the south are theIslamabad Capital Territoryand the province ofPunjab, whilst to the west lies the rest ofKhyber Pakhtunkhwa. The riverIndusruns through the division in a north-south line, forming much of the western border of the division. The total area of Hazara is 18,013km.

1.7) LOCATION OF THE AREA:

The area of field work is to the North East of Islamabad. The area has high relief, which ranges from 610m above sea level near Islamabad to 2982m at Miranjani near Nathiagali.

Figure 1: location of study area

1.8) CLIMATE: At Abbottabad, annual rainfall averages around 1,200millimetres (47in) but has been as high as 1,800millimetres (71in) , whilst in parts of Mansehra District such asBalakotthe mean annual rainfall is as high as 1,750millimetres (69in) . Due to its location on the boundary between the monsoonal summer rainfall regime ofEast Asiaand the winter-dominantMediterranean climateof West Asia, Hazara has an unusual bimodal rainfall regime, with one peak in February or March associated with frontal southwest cloud bands and another monsoonal peak in July and August. The driest months are October to December, though in the wettest parts even these months average around 40millimetres (1.6in) . Due to the high altitude, temperatures in Hazara are cooler than on the plains, though Abbottabad at 1,200m still has maxima around 32C (90F) with high humidity in June and July. Further up, temperatures are cooler, often cooler than theNorthern Areasvalleys due to the cloudiness. In winter, temperatures are cold, with minima in January around 0C (32F) and much lower in the high mountains. Snowfalls are not uncommon even at lower levels.

1.9) ACCESSIBILITY: The area is accessible through a carpeted road and is well known for tourism, so logistics and support are well developed.

CHAPTER 22.1.1) REGIONAL GEOLOGICAL SETTINGS: The area under discussion constitutes a part of the western Himalayas in Pakistan. It has been formed due to collision of Indian and Eurasian plates. Due to collision prominent regional structural elements have been developed along the consuming plate boundaries. The geology and structure of the western Himalayas has been well documented by several workers. Mujtaba, G., (1991) has shown that in western Himalayas, the Indus Suture Zone (ISZ) bifurcates into two structural zones, the Main Mantle Thrust (MMT) and the Main Karakoram Thrust (MKT). These sutures surround the obducted Kohistan Arc. The MKT, the northern suture, separates the intrusive and high grade metamorphic rocks of Eurasian Plate from the Kohistan Arc terrane. The Kohistan Arc terrane has, on the northern edge, deformed gabbros, volcanics and greywacke (Rakaposhi Volcanics Complex) that are intruded by tonalite, diorite and pegmatite. To the south, the rocks are composed of a deformed, layered igneous complex metamorphosed to granulite facies. The southernmost rocks of the Kohistan Arc are metasediments, amphibolites and granites. The MMT, the southern suture, separates the Kohistan Arc from the metasediments on the northern edge of the Indian Plate. It is the extension of the Indus-Tsangpo suture.

Figure 2: Regional Geological settings.The northern edge of the MMT is marked by sporadic occurrences of ultramafic rocks. The Indian Plate rocks are late Precambrian to early Paleozoic schists, marbles, gneisses and granitic gneisses that have been thrust southward over the Tertiary molasse sediments of the Rawalpindi and Siwalik Groups. Southward thrusting continues within the molasse sediments, which is the evidence of continued convergence of the Indian and Eurasian plates. As a result of tectonic activities several discontinuities in the stratigraphic record have been recorded. Since Jurassic more than 670 m of marine sediments have been deposited against more than 7500 m thick molasse from Miocene onwards ( Sheikh, M. Iqbal et al., 1993). Since then intense deformation, erosion and subsidence dominated and thick deposition of coarse clastic continental sediments took place. During the uplift and structural deformation for the last 1.5 million years (Plio-Pleistocene), erosion remained more pronounced than deposition, so the preserved sediments are thin and discontinuous bodies of alluvium and Eolian silts are seen.

2.1.2) MAJOR STRUCTURAL FEATURES: Hazara fold-thrust belt is a part of the Lower Himalayas and formed due to collision of Indo-Pakistan Plate with the Asian Plate during post-Eocene oroginic phase. Structurally, Hazara fold-Thrust belt represents a mega-synclinorium which is, along the Murree-Abbottabad road, is divisible into at least two synclinoria (Ghazanfar, 1990), i.e., the Nawashahr synclinorial complex towards Abbottabad and the much larger Kuza Gali synclinorial complex towards Murree. The two synclinorial complexes comprise a large number of NE-SW trending smaller structures. On the Murree-Abbottabad road, the Kuza Gali synclinorial complex bounded in the northwest by the Nathia Gali fault against the Hazara slates near the locality of Kalabagh. Rocks older than Mesozoic, however, are not exposed in the south-east, suggesting that the depositional axis of the basin was systematically shifting towards the southeast and southAs mentioned earlier, Hazara fold-thrust belt is bounded by Punjal (Khairabad) thrust fault in the north and that of Murree Fault in the south. Along the Punjal fault Precambrian sequence has been pushed over the Paleozoic and Mesozoic rocks; whereas, Murree faults abuts the Mesozoic and earlier rocks against the Murree formation. To the east and then north the two faults comes closer and finally coalesce for a time near Balakot. Very little structural studies have done in this part of northern Pakistan, due to generally thick vegetation cover, high relief and lack of subsurface data.

STRATIGRAPHYOF HAZARA AREA

2.2.1) INTRODUCTION: Hazara range is the northern most extremity of sedimentary succession of the North-western margin of the Indian plate. It is bounded by its north by the Panjal thrust on its southern side, by the main boundary thrust.The main highway from Rawalpindi to Peshawar is the dividing line between western limit of the Hazara range and the Kalachita Range.The staratigraphy of the hazara range start form Precambrian age(hazara formation) and ends at Miocene age (Murree formation). The stratigraphic succession of Hazara fold-thrust belt ranges in age from Eo-Cambrian to Pleistocene/Recent, interrupted by seven unconformities, with major absence of Middle and Upper Paleozoic sequence. Latif (1970) has divided the lithostratigraphic units into seven groups, each separated by an unconformity. He has further subdivided these groups into twenty one formations. (Mujtaba, 2010)

Table 2: Stratigraphic Sequence in lower Hazara as described by various authors (Abbasi, 2008)

Table 3: Generalized Stratigraphic Column of Hazara Area, NWFP, Pakistan (Iqbal, et al., 2007)

2.2.2) PREVIOUS WORK: The project area has remained a site of deep interest for the geologists working on stratigraphy and tectonics since a long time. A brief summary of the previous workis given below: Lydekker (1876, 1883) and Middlemiss (1896) carried out their workin Kashmir and Hazara. They established the broad outline of the geology in this region and named some of the rock units. Wadia (1931) explained the syntaxis of the northwest Himalaya on the basis of geosynclinals group of deposits laid down on the bed of Tethys against the northern shores of Gondwana land. Qureshi and Imam (1960) did the geological mapping of the area for iron and manganese ore deposits. Calkins, Offield, Abdullah and Ali (1975) mapped Balakot area at 1:125,000 and discussed its geology. They delt the stratigraphyand structure of a sequence of rocks that rangein age from Precambrian to Miocene. Structurally the area lies on the western flank of the HazaraKashmir Syntaxis and contains iron, manganese, high alumina, clays, gypsum, dolomite and graphite. This workwas done jointly by the Geological survey of Pakistan and U.S. Geological Survey. The main interest of field of Thakur and Gupta (1983) was the regional staratigraphy, paleontology and structure of Kashmir and Ladakh Himalayas. The Swiss geologists Bossart, Dorthe, Dietrich, Greco, Ottiger and Ramsay (1984) in collaboration with Institute of Geology Azad Jammu& Kashmir University described the lithological, Stratigraphic and structural features of HazaraKashmir Syntaxis. Ottiger (1986) did his work on the geology of Hazara-Kashmir Syntaxis. He reviewed the lithological Formations and rhythmic sedimentation in Lower Murree Formation in detail. Ghazanfar, Chuadry and Latif (1987) established three different sets of Stratigraphic sequences which occur close together in the region of Hazara-Kashmir Syntaxis.

PRE-CAMBRIAN Formations

Following formations belongs to Precambrian age in hazara range:(1) Hazara Formation(2)Tanawal Formation

2.2.3) HAZARA FORMATION: The name Hazara Formation has been formalized by Calkin and Ali (1969) for the slate series of Hazara of Middlemiss (1896), and Hazara Slates Formation of Marks (1961), and Attok slates of Waagen and Wynne (1872) , and Hazara Group of Latif (1970). The Formation has its type locality near Hazara District. Exposure around Baragali along Abbottabad-Nathiagali Road can be regarded as its type section.Lithology: The Formation consists of slate, phyllite and shale with minor occurrences of limestone and graphite layers. Slate and phyllite are green to dark green and black in color.

Figure 3: Hazara Slates.

Thickness: Limestone beds with maximum thickness of 150 m and calcareous phyllite gypsum from 30 to 120m thick are found in southern most Hazara.Fossils: Latif (1970) has reported fossils from the Formation similar to Protobolella. Age: Calkin (1969) correlated the Formation with Dogra Slates and assigned a late Precambrian age to Hazara Formation. Latif (1970) reported fossils showing that it may be lower Paleozoic in age. Crawford and Davies (1975) determined the age of the Formation by the Rb-Sr method. This age determination places the Formation in the Precambrian.

2.2.4) TANAWAL FORMATION: Wynne (1878) used the name Tanol group for the rocks of this formation. Middlemiss (1896) called them Tanol quartzite. Marks and Ali (1962) and Latif (1970) named them Tanol formation Calkins, Offield and Ali (1969) used the name Tanawal formation for this unit of rocks. The formation is well exposed in the north and south of Mansehra granite.

Lithology: The formation consists of Quartoze schist, quartzite and schistose conglomerate. The south of Mansehra granite the formation consists of medium grained quartzite and fine grained mica-quartz schist. To the north of Mansehra granite the formation mainly consists of granite and biotite muscovite-quartz schist.

Thickness: Ali (1962) estimated the thickness as 1666 m.

Contacts: Tanawal formation underlies Abbotabad formation and overlies Hazara formation in the area between Abottabad and Indus river. The upper contact with Abottabad formation in this area is unconformable. In the area between Abottabad and Garhi Habibullah the lower contact of the Tanawal formation with the Hazara formation is gradational.

Age: The presence of Tanaki conglomerate between Tanawal and Abottabad formation shows that the age of Tanawal formation is late Precambrian.

CAMBRIAN FORMATIONS2.2.5) ABBOTABAD FORMATION: Waagen and Wynne (1872) used the name below the trias for this unit of rocks. Middlemiss called it infra-trias. Latif (1970) named this unit as Abbottabad Group. Calkin, offield and Ali suggested the name Abbottabad Formation. Type locality of the formation is near Abbottabad town. Lithology: The Formation mainly consists of dolomite, quartzite and phyllite, with many lithologic changes from place to place. In Abbottabad area the formation contains beds of thick marble with phosphate deposit. Contacts: In Sherwan area the Formation has an unconformable lower contact with Tanawal Formation marked by the presence of a boulder bed or by lithologic change. Thickness: The thickness of the Formation is about 660 m at the type locality, 900 m in Tanol area, 833 m in Muzaffarabad area and 100 to 130 m in Garhi Habibullah syncline. Fossils: Calkin (1969) examined the fauna of carboniferous to Permian age from the formation. Recently Ikramuddin Ali and David examined the fossils of Hyolithes spp. in the formation which has been reported from the Cambrian of North America, Sweden and Russia. Age: According to Calkin (1969) the formation is carboniferous to Permian in age. On the basis of Hyolithes spp the formation placed in lower Cambrian.

JURASSIC FORMATIONS2.2.6) SAMANA SUK FORMATION: Middlemiss (1896) proposed the name Kioto limestone for the rocks of Samana Suk Formation in Hazara range.Lithology: In Hazara area the limestone of the formation is thin to thick-bedded and includes some dolomitic, ferruginous, sandy and oolitic beds.Thickness: The thickness of the formation is 366 m in Bagnotar section of Hazara area. Contacts: The lower contact is transitional with Shinawari Formation and upper contact is disconformable with Chichali Formation.Fossils: Calkins (1968) reported fossils of gastropods from northern Hazara. Latif (1970) reported fossils of Stylina sp., Corbula sp., Nucula sp. and Protocardia sp. from different parts of Hazara. Age: Age of the formation is Middle Jurassic indicated by its fauna.

Cretaceous formations2.2.7) KAWAGARH FORMATION: The name Kawagarh Formation was approved by Stratigraphic committee of Pakistan, against the older name Kawagarh Marls. Sattu Limestone of Calkines and Matin (1968) and Chanali Limestone of Latif (1970) in Hazara Area were formalized into Kawagarh Formation.

Lithology: The Nara sandstone member in the upper part is grey, brownish grey to dark grey, thick bedded, calcareous sandstone with some limestone interbeds. In northern Hazara Nara member was not developed and Kawagarh formation consists of grey, olive grey, light grey sublithlogic limestone with subordinate marl and calcareous shale.

Figure 4: Kawagarh Limestone.

Thickness: In Hazara the thickness of the formation varies from 45 m to 200 m, south to middle area.

Contacts: The formation has disconformable contact with overlying Hungu Formation of Paleocene age and underlying Lumshiwal formation of mainly Early Cretaceous.

Fossils: Latif (1970) has reported following foraminifers from southern Hazara: Globotruncana lapparenti, G.fornicata, G. concavata carinata, G. etc.

Age: On the basis of fauna the age of formation is regarded as Late Cretaceous

2.2.8) LUMSHIWAL FORMATION: The name Giumal Sandstone was given to the rocks of Lumshiwal Formation in Hazara area by Middlemiss (1896). Cotter (1933) used the name Main Sandstone Series for the same rocks. Wuch Khwar section in Nizampur area and Jhamiri village on Haripur Jabrian Road in Hazara are the reference sections of Lumshiwal Formation.

Lithology: In Hazara area the formation is mostly of marine origin consisting of quartose, ferruginous sandstone and dark rusty brown sandy limestone.

Thickness: In southern Hazara its thickness is 50m in northern Hazara its thickness varies from 20m to 10m.

Contacts: The lower contact with Chichali formation is transitional and upper contact with Kawagarh formation of upper cretaceous is disconformable.

Fossils: The upper most part of formation in northern Hazara has abundant fossil casts of brachiopods, gastropods and Ammonoids.

Age: The age of the formation in Hazara area is lower cretaceous.

2.2.9) CHICHALI FORMATION: Middlemiss (1896) called the rocks of Chichali Formation as Spiti Shale in Hazara. In southern Hazara the Formation is divided into three folds with almost type section lithology.

Lithology: In the lower part it consists of glauconitic sandstone with nodular silty, calcareous, phosphatic base. In the middle part it consists of glauconitic, sandy shale and dark pyritic unfossiliferous shale in the upper part. In northern Hazara the formation shows a facies change consisting of dark silty shale with some ferruginous calcareous and phosphatic nodules and is similar to Spiti Shale of Himalayas.

Figure 5: Belmenites

Thickness: In southern Hazara it is 33m thick while in northern Hazara its thickness is 34m to 64m.

Contacts: The lower contact with Samana Suk Formation is disconformable while the upper contact with Lumshiwal Formation is gradational.

Fossils: Ammonoids and belemnites of late Jurassic age have been recorded from Chichali Formation in Hazara area.

Age: In northern Hazara the age of the formation is Late Jurassic while in southern Hazara the age of the formation is Late Jurassic to Early Cretaceous.

Paleocene Formations:2.2.10) PATALA SHALES: The term Patala formation was formalized by Stratigraphic Committee of Pakistan for the Patala Shale of Davies and Pinfold (1937) and its usage was extended to other parts of the Kohat-Potwar and Hazara areas.

Lithology: It contains shale of brown and green color with interbeds of nodular limestone and carbonaceous material in Hazara area.

Figure 6: Patala Shale

Thickness: The thickness of formation is 182 m in Hazara area.

Contacts: Throughout its extent Patala Formation conformably overlies Lockhart Limestone. Patala Formation has shale with grayish color having thin beds of limestone. Contact between Margalla hill limestone and Patala Formation has been marked along Changla Gali road section.

Fossils: Latif 1970 reported smaller foraminifers from Hazara which includes Globorotalia elongata, Globigerina primitive, Triloculina trigonula. The larger foraminifers recorded by Raza and Cheema includes Assilinadandotica, a.granulosa, a. Spinosa.

Age: The age of formation is late paleocene in Hazara area.

2.2.11) LOCKHART LIMESTONE: Davies (1930) introduced the term Lockhart limestone for a Paleocene limestone unit in Kohat area and usage has been extended by Stratigraphic committee of Pakistan to similar units in Hazara area.

Lithology: In the Hazara area limestone is dark grey and black in color and contains intercalation of shale and marl. The limestone is generally bituminous and gives feted smell on fresh surface.

Figure 7: Nodular Lokhart Limestone.

Thickness: The thickness of unit is 242m in Hazara area.

Contacts: The formation conformably and transitionally overlies and underlies the Hungu Formation and Patala Formation respectively. The contact between Lockhart Limestone and Patala Formation has been marked in Changla Gali road section.

Fossils: Raza (1967), Cheema (1968), and Latif (1970) have reported a number of foraminifer from Hazara area including Lockhartia, Conditi, Globorotalia uncinata, Globigerina tringularis, Texularia sinithvillensis etc.

Age: The above mentioned fossils indicated Paleocene age of unit.

Eocene Formations2.2.12) MARGALLA HILL LIMESTONE: The term Margalla Hill Limestone of Latif has been formally accepted by Stratigraphic committee of Pakistan for the Nimmulitic formation of Waagen and Wynee (1872), the upper part of Hill limestone of Wynne(1873) and Cotter (1933), and part of Nummlitic Series of Middlemiss .The name is derived from the Margala Hills in Hazara. Lithology: The formation consists of limestone with subordinate marl and shale. The limestone is grey, weathering pale grey, fine medium grained, nodular, medium to thick bedded and rarely massive. The marl is grey to brownish grey while the shale is greenish brown to brown in color. Contacts: The lower and upper contacts with the Patala Formation and Chorgali Formation are conformable. Fossils: Foraminiferas, mollusks and echinoids are common in the formation. Raza (1967), Cheema (1968) and Latif (1970) recorded number of foraminifers from the formation, including Assilina graulosa, A.laminosa, A.Lokhartia Conditi, L.Opercoloia jiwani, O.etc Age: The above listed Foraminiferes indicate the Early Eocene Age of the formation

2.2.13) CHORGALI FORMATION: The term Chorgalibeds of Pascoe (1920)has been formalized as Chorgali formation by theStratigraphicCommitteeof Pakistan.Latif (1970) used thenameLora Formation for the rocksof Chorgali formation inthe Hazara area.Lithology: In Hazara area theformation is composedof thinlyinter-bedded limestone and marl which are light to pale grey and weather light yellow tocream. Inthe KalaChitta, the formation consists thin to mediumbed grey limestone with subordinate marl. The limestone is light lynodular and contains chert lenses.Fossils: A richfossil assemblagesincludingforaminiferas, mollusks andostracodes hasbeenReported by Davies and Pin fold(1 9 37 ),Eames(1 9 5 2),Gill(1953)and Latif (1970c).

Age: The age ofthe formation is Early Eocene 2.2.14) KULDANA FORMATION: Middlemiss (1896) used the name Kuldana series, Latif called Kuldana beds to the rocks of Kuldana formation. Type section: The type section is near Kuldana village in Hazara District.Lithology: The formation is composed of shale and marl with occasional beds of sandstone, limestone, conglomerate and bleached dolomite. In Hazara area shale and marl are dominant. The shale is brown, gypsiferous and arenaceous. The marl is brown with few beds of fibrous gypsum. Thickness: The thickness of the formation is 150 m in Hazara area.

Contacts: In Hazara area the Formation has a conformable contact with underlying Chorgali Formation and upper contact with Murree Formation is disconformable.

Fossils: Remains of foraminifers, gastropods, bivalves have been reported from the formation.

Age: The age of the formation is Middle Eocene. Miocene FORMATIONs

2.2.15) MURREE FORMATION: The name Murree formation has been formalized by the Stratigraphic committee of Pakistan for the Mari group of Wynne (1974)and Murree beds of Lydekker (1876). A type section has been designated to the north of Dhok maiki in the Campbellpur Distric.

Lithology: The formation is composed of a monotonous sequence of dark red clay and grey sandstone with subordinate intraformational conglomerate. Calcareous sandstone is present at the base of the formation. This section has been designated as fatehjang member, after the fatehjang zone" of pilgrim (1918). Thickness: The formation is 180 to600 m thick in the northern salt range. It is 3,030 m thick in northern potwar. Contacts: The lower contact of the formation is with various formations of the Eocene age. The upper contact is transitional with Kumlial formation.

Fossils: The formation is poorly fossiliferous and contains only few plant remains but from the fatehjang member fossils of mammals are recorded. Age: The age the formation is early Miocene on the basis of above mentioned fossils

CHAPTER 3GENERAL STRUCTURES:3.1) FOLDS: The termfoldis used ingeologywhen one or a stack of originally flat and planar surfaces, such assedimentarystrata, are bent or curved as a result of permanentdeformation. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (fault bend fold), at the tip of a propagating fault (fault propagation fold), by differential 3.2) FOLD TERMINOLOGY IN TWO DIMENSIONS: Looking at a fold surface in profile the fold can be divided intohingeandlimbportions. The limbs are the flanks of the fold and the hinge is where the flanks join together. The hinge point is the point of minimum radius ofcurvaturefor a fold. Thecrestof the fold is the highest point of the fold surface, and thetroughis the lowest point. Theinflection pointof a fold is the point on a limb at which theconcavityreverses, on regular folds this is the mid-point of the limb.

3.3) FOLD TERMINOLOGY IN THREE DIMENSIONS: The hinge points along an entire folded surface form a hinge line, which can be either acrest lineor atrough line. Thetrend and plungeof a linear hinge line gives you information about the orientation of the fold. To more completely describe the orientation of a fold, one must describe theaxial surface. The axial surface is the surface defined by connecting all the hinge lines of stacked folding surfaces. If the axial surface is a planar surface then it is called theaxial planeand can be described by thestrike and dipof the plane. Anaxial traceis the line of intersection of the axial surface with any other surface (ground, side of mountain, geological cross-section).A fold axis is the closest approximation to a straight line that when parallel to itself moved, generates the form of the fold. (Davis and Reynolds, 1996 after Donath and Parker, 1964; Ramsay 1967). A fold that can be generated by a fold axis is called acylindrical fold.

Figure 8: terminologies of fold.3.4) FOLD SHAPE: It is necessary to convey a sense of the shape of the fold. A fold can be shaped as achevron, with planar limbs meeting at an angular axis, ascuspatewith curved limbs, ascircularwith a curved axis, or as elliptical with unequalwavelength

Figure 9: Cylindrical fold with axial surface not plane.3.5) FOLD TYPES: Anticline: linear, strata normally dip away from axial center,oldeststrata in center.

Figure 10: Anticline. Syncline: linear, strata normally dip toward axial center,youngeststrata in center.

Figure 11: Syncline. Chevron: angular fold with straight limbs and small hinges Recumbent: linear, fold axial plane oriented at low angle resulting in overturned strata in one limb of the fold. Parasitic: short wavelength folds formed within a larger wavelength fold structure - normally associated with differences in bed thickness Disharmonic: Folds in adjacent layers with different wavelengths and shapesZ-FOLD:

Z-foldIn aparasitic fold, an asymmetric fold whose profile is Z-shaped, reflecting its location on the respective limb of a major fold

Figure 12: Z and S fold.

S-FOLD: An asymmetricalparasitic foldwhose approximately S-shaped profile, when observed down theplungeof thefold axis, indicates its position on the right limb of the majoranticline, but not on thesyncline.

Figure 13: some types of folds.

3.6) FAULT: Ingeology, afaultis a planarfractureor discontinuity in a volume ofrock, across which there has been significant displacement. Large faults within the Earth'scrustresult from the action oftectonicforces. Energy release associated with rapid movement onactive faultsis the cause of mostearthquakes. Afault lineis the surface trace of a fault, the line of intersection between the fault plane and the Earth's surface. The two sides of a non-vertical fault are known as thehanging wallandfootwall. By definition, the hanging wall occurs above the fault and the footwall occurs below the fault.

Figure 14: hanging wall and foot wall.3.7) FAULT TYPES: Geologists can categorize faults into three groups based on the sense of slip:DIP SLIP FAULT: Dip-slip faultscan occur either as "reverse" or as "normal" faults. A normal fault occurs when the crust is extended. Alternatively such a fault can be called anextensional fault. The hanging wall, which got its name from miners hanging their lanterns on this wall, moves downward, relative to the footwall, which gets its name from the miners who walk on this wall. A downthrown block between two normal faults dipping towards each other is called agraben. An upthrown block between two normal faults dipping away from each other is called ahorst. Low-angle normal faults with regionaltectonicsignificance may be designateddetachment faults.

Figure 15: Dip slip fault.

REVERSE FAULT: A reverse fault is the opposite of a normal fault the hanging wall moves up relative to the footwall. Reverse faults indicate shortening of the crust. Thedipof a reverse fault is relatively steep, greater than 45.NORMAL FAULT: Fault in which the hanging wall has moved downward relative to the footwall.

Figure 16: Normal and reverse fault.

STRIKE SLIP FAULTS: The fault surface is usually near vertical and the footwall moves either left or right or laterally with very little vertical motion.Strike-slip faultswith left-lateral motion are also known assinistralfaults. Those with right-lateral motion are also known asdextralfaults.

Figure 17: Schematic illustration of strike slip fault.

OBLIQUE SLIP FAULTS: A fault which has a component of dip-slip and a component of strike-slip is termed anoblique-slip fault. Nearly all faults will have some component of both dip-slip and strike-slip, so defining a fault as oblique requires both dip and strike components to be measurable and significant.

Figure 18: Oblique slip fault.CHAPTER 4:Day 1, stop 1:4.1.1) INTRODUCTION: On the first day of our trip we went to the Jabri area of Hazara. We were standing at the lesser Himalayas. There we observe the Hazara slates of Pre Cambrian age. The main Hazara thrust fault is passing through the area. We were standing on the fault zone. The road was in between the fault zone. Fault is moving from north. The movement of fault is in both horizontal and vertical directions.Here we observed the Hazara slates which is discussed above in the portion of stratigraphy.4.1.2) FAULT ZONE INDICATION: Breccia Intense fracturing Drag foldThere the rocks of Eocene age were present and the rock of Paleocene, Cretaceous and Jurrasic age were missing.PresentEocene

MissingPaleocene

MissingCretaceous

MissingJurassic

Then we draw the rough diagrams of the outcrop. We observe faults and folds there which are attached with the report.

4.2.1) Day 2nd On this day we observe the following formations.FormationsDescription

Kuldana FormationShale with Gypsum with inter-beds of limestone

Chorgali FormationLimestone with inter-layers of shale/marl

Margala Hills LimestoneLimestone with shale/marl inter-beds

Patalla ShalMarly shale with few thin limestone beds

Lockhart FormationLimestone with occasional marl/shale layers

Kawagarh FormationLimestone, wilt shale in lower part

Lumshiwal FormationSand, siltstone with shale inter-layers

Chichali FormationShale beds

Samana suk FormationLimestone with intra-formational conglomerate

The overall details of the formations are mentioned in the portion of stratigraphy.

4.2.2) GET A BEARING: A bearing is a measurement of direction between two points. Bearings are generally given in one of two formats, an azimuth bearing or a quadrant bearing.An azimuth bearing uses all 360 of a compass to indicate direction. The compass is numbered clockwise with north as 0, east 90, south 180, and west 270. So a bearing of 42 would be northeast and a bearing of 200 would be southwest, and so on.For quadrant bearings the compass is divided into four sections, each containing 90. The two quadrants in the northern half of the compass are numbered from 0 to 90 away from north (clockwise in the east, counterclockwise in the west). In the southern half of the compass, the two quadrants are numbered away from south (counterclockwise in the east, clockwise in the west).

Figure 19: Quadrant Bearing.Quadrant bearings are given in the format of N 40E (northeast), S 26W (southwest), etc. Whenever you measure a quadrant bearing, it should always be recorded with north or south listed first, followed by the number of degreesaway from north or south, and the direction (east or west) away from north or south. In other words, you would never give a quadrant bearing as E 40N or W 24S.Your compass may be an azimuth compass or it may be divided into quadrants. If you have an azimuth compass and are given a quadrant bearing, youll have to divide it into quadrants in your head, and the same goes for quadrant compasses if you are given an azimuth bearing.4.2.3) MEASURING A BEARING: So, youre in the field with your map at point A and want to get to point Bhow do you accomplish this? The first thing you need to do is determine the bearing from point A to point B. There are two ways to go about this.The easiest way, is to carry a protractor with you when youre in the field. If you have a protractor with you, place it on the map so it is oriented parallel to a north-south gridline, with the center of the protractor on point A (or on a line drawn between points A and B). Once you have done this, you can simply read the bearing you need to go off of the protractor.If you dont happen to have a protractor with you, you can determine the bearing you need using your compass. To do this, place your compass on the map so that the edge of your compass is oriented parallel to a north-south gridline and the center of your compass is on the line between points A and B.

Figure 20: Map Bearing.

Now rotate the map and compass together until the north arrow on the compass points to 0 on the graduated circle. You can then approximate the bearing you need by estimating where the line between A and B crosses the graduated circle.It is probably at about this point that, if you are using a Brunton compass (and some others as well), you are probably noticing that the east label is on the wrong side of the compass (west of north).

Day 3rd, Stop 1:4.3.1) INTRODUCTION: Here we observed the extension of Mansehra granites. They had a uniform texture and represented Augen gneisses of quartz and feldspar composition. Some of it was converted to milonite and represented shear zone. The gneissosity was shown by gneiss banding.

Figure 19: Mansehra granites fine grained with light colored augen gneissesHere we observed Dolerite dykes intrusion. White feldspar. Quartzite intrudes in the granite.

4.3.2) Stop 2:INTRODUCTION: Here on one side of the road, we could see all variety of schists. On the other side, it was a landscape. On the back side of the mountain, there was Balakot Bagh fault where there was a displacement of 5 m in 2005 Earthquake. The red colored formation was Murree Formation on top and white color formation showed Abbottabad formation. Also there were some fault scars which were the geomorphic indicators of the faults.

Murree formationAbbotabad formation Figure 20: Murree and Abbotabad formationsIn the foot of the mountains, there were Alluvial fans in which finer particles were at the top and coarser are at the bottom.

Figure 21: Alluvial fan..kunhar river.4.3.3) Stop 3: Then we went to the balakot area. There we observe the Balakot Fault zone.BALAKOT FAULT REGION: Balakot tectonic ridge lie on the active hanging wall (anticline) imbigrated between southern and northern segments of muzafarabad thrust.this active anticline is form because of the active folding of the hanging wall of muzaffarabad fault.the Holocene terraces is tilted,uplifted and folded in andi anticline and also in balakot hanging wall anticline.COORDINATES: 34 33 27N 73 21 22E.Fault is in NS trend. Fault is vertical steeply dipping. In the north there is red valley stuff. On the west lies the Hanging wall which is the older rocks (shale, clay)In the east lies the foot wall there the rocks are carbonate rocks.

DAY 4

4.4.1) RESISTIVITY SURVEY INTRODUCTION:

The purpose of electrical surveys is to determine the subsurface resistivity distribution by making measurements on the ground surface. From these measurements, the true resistivity of the subsurface can be estimated. The ground resistivity is related to various geological parameters such as the mineral and fluid content, porosity and degree of water saturation in the rock. Electrical resistivity surveys have been used for many decades in hydrogeological, mining and geotechnical investigations. More recently, it has been used for environmental surveys. The resistivity measurements are normally made by injecting current into the groundthrough two current electrodes (C1 and C2 in Figure 1), and measuring the resulting voltagedifference at two potential electrodes (P1 and P2). From the current (I) and voltage (V)values, an apparent resistivity (pa) value is calculated.pa = k V / I

Figure 22: Resistivity method

Figure 23: concept of Resistivity Measurement.

where k is the geometric factor which depends on the arrangement of the four electrodes. In a later section, we will examine the advantages and disadvantages of some of these arrays. Resistivity meters normally give a resistance value, R = V/I, so in practice the apparent resistivity value is calculated bypa = k RThe calculated resistivity value is not the true resistivity of the subsurface, but an apparentValue which is the resistivity of a homogeneous ground which will give the same resistance Value for the same electrode arrangement. The relationship between the apparent resistivity and the true resistivity is a complex relationship. To determine the true subsurface resistivity, an inversion of the measured apparent resistivity values using a computer program must be carried out. The distance between two current and potential electrodes is changed and readings are taken.

4.4.2) TRADITIONAL RESISTIVITY SURVEYS: The resistivity method has its origin in the 1920s due to the work of the Schlumberger brothers. For approximately the next 60 years, for quantitative interpretation, conventional sounding surveys (Koefoed 1979) were normally used. In this method, the centre point of the electrode array remains fixed, but the spacing between the electrodes is increased to obtain more information about the deeper sections of the subsurface.

Figure 24: the Conventional four electrode array

The measured apparent resistivity values are normally plotted on a log-log graph paper. To interpret the data from such a survey, it is normally assumed that the subsurface consists of horizontal layers. In this case, the subsurface resistivity changes only with depth, but does not change in the horizontal direction. A one-dimensional model of the subsurface is used to interpret the measurements. Despite this limitation, this method has given useful results for geological situations (such the water-table) where the one dimensional model is approximately true. The most severe limitation of the resistivity sounding method is that horizontal (or lateral) changes in the subsurface resistivity are commonly found. Lateral changes in the subsurface resistivity will cause changes in the apparent resistivity values that might be, and frequently are, misinterpreted as changes with depth in the subsurface resistivity. In many engineering and environmental studies, the subsurface geology is very complex where the resistivity can change rapidly over short distances. The resistivity sounding method might not be sufficiently accurate for such situations. Despite its obvious limitations, there are two main reasons why 1-D resistivity sounding surveys are common. The first reason was the lack of proper field equipment to Copyright (1999) M.H.Loke carry out the more data intensive 2-D and 3-D surveys. The second reason was the lack of practical computer interpretation tools to handle the more complex 2-D and 3-D models. However, 2-D and even 3-D electrical surveys are now practical commercial techniques with the relatively recent development of multi-electrode resistivity surveying instruments (Griffiths et al. 1990) and fast computer inversion software (Loke 1994).

4.4.3) APPLICATIONS:

Electrical resistivity of soils and rocks correlates with other soil/ rock properties which are of interest to the geologist, hydrogeologist, geotechnical engineer and/or quarry operator. Several geologic parameters which affect earth resistivity (and its reciprocal, conductivity) include: clay content, groundwater conductivity, soil or formation porosity, Degree of water saturation.

4.4.4) READINGS COLLECTED IN FIELD:currentpotential

AB/2MN/2Resistivity(ohm.m)Standard Deviation

5121.4390.157%

10119.6400.178%

10219.7700.077%

15217.8920.563%

20219.1320.414%

25520.7640.823%

4.4.5) STOP 1: The first stop we made was at a place called Khota Kabr. It has now been renamed to Muslimabad. Mainly we observed Hazara slates, dark brown in color. Hazara formation is oldest sequence and is equivalent to salt range formation in age. It consisted of Precambrian and Paleozoic sequences.Medium-corse grained sandstone especially of the greywacke variety was also seen. Other lithologies present were phyllites, schists, argillite, clays and metasediments.

Figure 25: Hazara slates. Moving further we saw a sequence showing chaotic channel fill deposits which were overlain by uniform sediments. The top of the uniform sequence marked the terrace which represented the maximum level of the stream at the time of formation. The uniform sequence was formed in a fluvial environment and the chaotic fill indicated hill slope deposits with no internal organization.

Then we observed Tannaki boulder bed which marked a major unconformity and was at the base of Abottabad formation.

Tannaki boulder bed consisted of conglomerates at the base and massive boulders at top. The conglomerates were blackish in color and both clast supported and matrix supported variety was observed. There was no consistency in grain size.

Hazara SlatesTanaki boulder bed Figure 26: Hazara slates over lain by Tannaki boulder bed

1