the foreword - brunel university london · dynamics during the late-glacial to early holocene. ......

Rapidly Changing Large Lakes and Human Response

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THE FOREWORD

Lakes are excellent archives of palaeoenvironmental changes, as they often have a continuous sedimentation. Sedimentation rates are often high and in some cases annual resolution is possible, e.g. when the sediment is laminated or when the age control is robust. Therefore it is possible to relate the scale of changes to a societal time scale. Humans often settle at proximity of lakes as they are a good source of freshwater and food. When a geo-hazard or a hydro-meteorological hazard occurs, the lacustrine sediment, owing to the possibility to apply multiproxy analyses, is a very good archive of these changes (tephras, high energy layers, mixed layers). Moreover human activities are often themselves directly recorded in lake sediment itself (indicators of agriculture, pollutants, deforestation).

Global warming, rapid past climatic changes and natural hazards have affected in various ways the extent and properties of large water bodies in SW Asia and central Asia, often very dramatically, as lakes and inland seas act as amplifiers of the effects of these forcings. For example, in the last decades, the Aral Sea level has gone catastrophically down with the restriction of the main inflowing rivers; while the Caspian Sea level, at the same time, has gone up for unclear reasons (3 m between 1977 and 1995, 100 times faster than gobal sea level changes). In many regions, local populations depending on these water sources for drinking or for economical activities have been deeply affected. Because sea-level variations can greatly affect the surface area of the water bodies, they can also intrude onto the land surface components; and therefore affect not only coastal communities (e.g. fisheries, harbours, transports) but also farmland and urban areas at a distance from the ‘normal’ position of the shores.

The selected area (Aral Sea, Caspian Sea and central Turkey lakes) is characterized by:

- The birth of agriculture perhaps in reaction to the drought of the Younger Dryas,

- Many large civilisations have come and gone,


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- An especially strong impact of the 4.2 ka global climatic event on the Mesopotamian and Harappan civilisations,

- The shifting contact between the northern Eurasian climatic system (dominated by the westerlies from the Atlantic Ocean) and the Indian monsoon.

- Natural hazards such as earthquakes and volcanic explosions, droughts and floods.

The recently observed changes in the region will be place in the context of Late Quaternary changes, specifically with the aim of informing end-users of the full range of possible changes in lake levels, water salinities, etc, … (Leroy et al., 2010).

This project will bring together researchers who will present

evidence for rapid changes in water levels and quality during the Quaternary in SW Asia, including sedimentological, geomorphic, archaeological and palaeoecological aspects; i.e. the full range of Quaternary specialities will be involved. Analogues for future change, as well as how humans were impacted by these dramatic changes in the past, will be debated.

Suzanne Leroy Hamid Lahijani

Workshop Coordinators


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Contents Cat-Scan analysis of sedimentary... 1

Abbasian et al Environmental changes during… 2

Akabri Azirani et al Lakes of the Iranian plateau… 3

Alizadeh et al Catastrophic flood of Caspian… 4

Chepalyga et al Environmental Impacts… 7

Okuku Archibong et al Holocene lake records and… 8

Chen et al Changes in the vegetation of… 9

de Beaulieu et al “Hidden species” as part of… 10

Djamali et al Dust storm, new phenomenon… 11

Gholami et al The Ways for Constant and… 13

Golubov et al Molecular and Isotopic Evidence… 15

Gregg et al Geological and Geographical… 16

Gürbüz et al Distribution and relevance of… 17

Haghani et al Middle to Late Holocene climate… 19

Huang et al Oil seeps in the Caspian Sea… 20

Ivanov et al Ground penetrating radar studies… 22

JOL et al Late Pleistocene and Holocene sea… 24

Kakroodi et al


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Application of cladoceran proxy… 25 Kattel et al

Late Pleistocene-Holocene fan… 27 Kazanci et al

Dating Caspian Sea Level Change… 29 Kroonenberg et al

Holocene vegetation history and sea… 31 Leroy et al

The magnetic susceptibility behavior… 32 Naderi Beni et al

Late Little Ice Age highstand… 33 Naderi Beni et al

Title: Trophic status of Caspian Sea… 35 Nasrollahzadeh Saravi et al

The effects of the current system… 37 ÇELEBİ et al

A record of Late Quaternary continental… 39 Marie-Claire et al

A High-resolution Record of Holocene… 41 Sharifi et al

Geomorphological evidence of the level… 43 Maghsoudi et al

Palynological reconstruction of the Cas… 45 Ramezani et al

Natural and artificial barriers… 47 Nokandeh et al

The story of a vanishing lake… 48 Sharifi et al

Climate and Environmental History… 50 Tolo et al

Sasanian Sub-aquatic: The Underwater… 52 Rensburg et al

A Programmatic Research Plan… 53 Wigand et al

Use of Multiple Proxy Data to Track… 55 Wigand et al


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1

Cat-Scan analysis of sedimentary sequences: A case study of South Caspian Sea Hedieh Abbasian1, Hamid Alizadeh Lahijani2, Abdolhossein Amini1

1: School of Geology, College of science, University of Tehran, Tehran, Iran 2: Iranian National Institute for Oceanography, Tehran, Iran

A depositional sedimentary environment is defined in terms of physical, biological and chemical variables, thus a change in the environmental conditions and their instability during sedimentation can be followed by a change in the diversity, distribution and abundance of planktonic and benthic organisms. These factors are analyzed in the offshore sediments of the South Caspian Sea (Langroud-Roudsar Coasts).

This study examines the distribution of recent trace fossils and sedimentary structures in the offshore sediments of the South Caspian Sea, using Ct-Scan (Computerized Co-axial Tomography) technique.

The trace fossil assemblage (Helminthoidichnites, Planolites, Cochlichnus, and Treptichnus) and depth of cores under study show characteristics of the ichnofacies known as Mermia. The Mermia ichnofacies is characteristic of fine-grained sediments and occurs in low energy and permanently subaqueous zones of the non-marine environments. Its significant reduction in density and burrowing types suggest instability of conditions for spreading organisms.

In addition, thin to very thin lamination with light and dark colors are the most important primary structures in these facies, visible in Ct-Scan images. Depositional processes including proximal low density turbidity currents, distal high density turbidity currents, hyperpicnal currents, and nepheloid layers are recognized along the studied sequences. Rapid changes in the physiochemical parameters and trophic level of the studying trace fossil are related to such depositional processes. Email: [email protected]

mailto:[email protected]�


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Environmental changes during late-glacial - early Holocene in northwestern Iran: A case of study from Lake Neor in Talesh Mountains

Tayebeh Akabri Azirani

Department of physical geography- University of Tehran

In this research, results of the pollen analysis of a sediment core from Lake Neor (NW Iran) for reconstructing the past environmental Conditions (vegetation and climate change) are presented and the contribution of the present data to global climatic change are discussed. We used 45 samples with 5 cm intervals from the 300 cm of lower part of a 800 cm long core. The results revealed that the Lake Neor region has had a rich floristic region with a variety of vegetation types.

This high resolution pollen study provides an image of the vegetation dynamics during the late-glacial to early Holocene. Our research showed the vegetation change from ~12,885 to ~7,800 years B.P.

We detected the last warm phase of the late-glacial (A1 pollen zone), the last cold phase of lateglacial or Younger Dryas (A2 pollen zone) and also the early Holocene (B1, B2, & B3 zones) by interpreting the pollen variations of main plant taxa around Lake Neor. Chenopodiaceae, Artemisia, and Poaceae with many Irano-Turanian steppe taxa formed the dominant herbal vegetation cover during the late-glacial while Ephedra, Quercus, and Betula were dominant arboreal pollen at the same time. The tree pollen was absent from the area during Younger Dryas. It implied colder and dryer climatic condition during this interval. As a result, the palynological analysis as well as dating result included that the ecological changes in Lake Neor shows that the late-glacial climatic variations have well affected northwestern Iran in a similar trend to Europe.

Email: [email protected]


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Lakes of the Iranian plateau: an integrated program for their environmental investigation Lahijani, H.1, Djamali, M.2, Pourmand, A.3, Sharifi, A.3, Naderi Beni, A.1, Hamzeh, M.1, Pourkerman, M1

1: Iranian National Institute for Oceanography, Iran 2: Institut Méditerranéen de Biodiversité et d’Ecologie (UMR CNRS–IRD–Aix-Marseille Université), France 3: Rosenstiel School of Marine and Atmospheric Science, University of Miami, US

There are more than 400 lakes with different limnologic properties and geographical setting in the Iranian plateau. They lie in different climatic zones and prone to record past climatic and environmental variations. They provide natural resources for the rim societies, so their health is a key factor in sustainable development of the societies. Many of these lakes are registered in the Ramsar Convention on Wetlands of International Importance due to their significant plant/animal biodiversity. Historically, there are some evidences that show the interrelationships between the emergence and decline of civilizations with the health and hydrology of the lakes around which they are found. During the last decades many of the Iranian lakes have completely desiccated or experienced severe changes in their physic-chemical charachteristics.

This program tries to investigate and model the present environmental status and past changes in some of the most important lakes in Iran to give an insight into the likely future changes and their impacts on human societies based on geological, limnological, paleoecological and historical evidences.




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Catastrophic flood of Caspian depression during Extreme Inundation Epoch (Khvalynean transgression): environment changes and influence on human civilization.

Chepalyga L. Andrey

1: Institute of Geography RAS, Staromonetny per. 29, 119017, Moscow, Russia [email protected]

During Last Glacial deglatiation (17-10 Ka BP) territory of NW Eurasia effected by events of Extreme Inundations Epoch (EIE) related to the Great Flood or biblical Noah’s Flood (Chepalyga 2002, 2003). Events of EIE held place within four landscapes: marine lowlands (marine transgressions), river valleys (superfloods), watersheds (thermocarst lakes) and slopes (solifluction flows). The space of these events cover of Eurasia territory between Atlantic and East Siberia, Subarctic and southern seas and mountains and cover space more than 10 mln km2. Marine transgressions of Ponto-Caspian basins forms Cascade of Eurasians basins (CEB) with set of sea lakes: Aral Sea, Caspian, Black Sea, Sea of Marmara connected by spillways-straits: Uzboy, Manych-Kerch, Bosphorus, Dardanelles. During Great Flood stage of EIE (17-15 Ka BP) the Khvalynean basin appeared to be an epicenter of EIE events. Sea level raised on just 200 m., waterspace increased 6 times and reach to 1 mln km2. Water volume increased two times (up to 130 000 km3), salinity was 10-12‰. It is waters overflow Caspian depression and flew along the Manych-Kerch spillway (900 km long, 10-50 km wide) to the Black Sea depression. Water discharge of this spillway reached 10-50 000 m3/sec. General characteristics of marine-lake basins of CEB are: total aquatorium space – 1 mln 500 000 km2, including flooded space – more 1 mln km2 , water volume – up to 700 000 km3 , water system of CEB covered the space 3000 km from East to West and 2500 from North to South.



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Catastrophic character: in the peak of Khvalynean transgression sea level raised just 200 m during 100-200 years with rate 1-2 m/year.

It is 10 times more then recent catastrophic rising Caspian Sea level at the end of XX c. (2,5 m per 25 years). Coastline migration rate reached 10-20 km/year or 50 m per day. Flooded space reach 1mln km2, so each year population in Ponto-Caspian basin loosed 10 000 km2 the most fertile land (deltas, coastal plains, flood-plains and lower river terraces). It was real catastrophe and stress for population.

Human adaptation to flood events. Marine basins and spillways of EEI especially CEB (Ponto-Caspian) influenced on Early Man migrations. Cultural connections and tools exchange between southern regions (Caucasus, Iraq) and East Europe was interrupted by appearance water barrier of Manych-Kerch strait. Under of EIE events the first elements of productive economy as a base of Earliest civilizations appeared. Flood events of EIE effected inundation of the most productive land and primitive model of feeding (hinter-gathering) become useless. This was multiplied by many refugees from flooded regions. As a result it was increasing of density population and stress on the edge of surviving. The only way to survive was fundamental change of food production strategy: appearance of productive economy (cattle breading, crops and transport).

Language evolution. EIE influenced on early history of the earliest human language of the modern type especially on earliest diversification of languages. The time of the first diversification of the original language near 17-15 ka was calculated by ethimohronological method (Starostin, 2000). This time coincides with beginning of great inundations during EIE. Numerous inner water basins could provocate appearance of water barriers which isolated human communities each other. This isolation led to subsequent division of human communities, resulting in developing of the new languages. The oldest reconstructed language is Borean super-super family spreaded over most territory of Holarctic 17-15 ka (Hell-Man, 2009).


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Later about 12 ka from this language were separated on four superfamilies: Eurasiatic (Nostratic), Sino-Caucasian, Afroasiatic and Austric (Nikolaev, 1991).

On Pleistocene – Holocene boundary (10 ka) and Early Holocene Eurasiatic superfamily language was separated on some families: Altaic (8 ka), Indo-European (7 ka) and others. Appearance and wide spread of recent language families coincides with termination of EIE (10 ka) and seems to be as a result of EIE events. The same time first civilization appeared on the base of productive economy: agriculture, construction and sailing and also was triggered by EIE events. So main human evolution events (first language diversification and productive economy beginning) connected not with climatic extremes (LGM), but much more with inundation events of EIE.




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Environmental Impacts Linking Climate to Ecosystem Changes: Physiological Background and Ecological Implications in West African Climate Coastline EDIANG Okuku Archibong, EDIANG Aniekan Archibong 1: Marine Division Nigerian Meteorological Agency pmb1215 Oshodi Lagos Nigeria. 2: The Nigerian Maritime Administration and Safety Agency, NIMASA, 6 Burmal Road, Apapa, Lagos,Nigeria.

On record, data on lakes and reservoirs are critical to the

understanding of the global hydrological cycle and information and their freeze and break-up dates is useful in the evaluation of climate change, also the Quaternary period is characterized by dynamic and mobility of biological and historical phenomenon of all kinds. During the Quaternary and especially in the Holocene of ecosystem has been subjected to deep transformation globally.

The tropics play a critical role in the Earth system. Climate change in the tropic, both natural and anthropogenic, has the potential to alter: Upwelling and marine food chains, the rate of which pollutants and green house gasses accumulate in the atmosphere, the intensity and extent of oceanic oxygen zones with consequences for higher tropic levels as well as for oceanic nutrient budget.

The attempt in this study is to improve the understanding of the transport processes, especially the changes in physical and chemical properties of dust particles during their transport from source regions to the Ocean environment and their potential feedback of marine ecosystems to dust deposition.

The results showed that Coastal environment is generally coated with dust and visibility is relatively lower in dry than rainy season because of the importance of descending motion for true dust storms and that of the transverse indirect circulation.

The study also revealed that barriers to successful information sharing must be managed to allow the delivery of accurate and timely information to those able to use it for greatest protection of those in coastal regions in West Africa and Nigerian coastline especially.

The research study conclude, over the last decades ,that there is lack of data and logistical difficulties for global change research in the West African Coastal region [email protected]



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Holocene lake records and moisture changes of Arid Central Asia

Fa-Hu Chen*, Xiao-zhong Huang, Li-ya Jin 1: MOE Key Laboratory of West China's Environmental System; Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou 730000, China

Holocene climate evolution in Arid Central Asia (ACA) is

reconstructed and mapped by summarizing and comparing data from 20 lake sites based on a unified time scale of calendar years BP, after correction for possible carbon reservoir effects. Despite their different latitudes and sizes, most of these lakes demonstrate several shared features, including desiccation during the early Holocene, abrupt increase in lake levels apparent in the early middle-Holocene, and subsequent high lake levels and humid climate in the middle to late Holocene. Notwithstanding differences in the timing and duration of positive water budgets throughout the latter half of the Holocene, an increasingly moist ACA beginning in the mid-Holocene is in contrast with increasingly dry conditions in the domain of the Asian Summer Monsoon. The pattern of ACA climate change is explained by changes sea surface temperatures of the North Atlantic area, and it is closely related to westerly wind speed controled water vapor advection and evaporation upstream from the Mediterranean, Black, and Caspian Seas in boreal winter. Therefore, the lake status in arid central Asia is more connected with westerlies caused precipitation during middle Holocene. Some discussions have been made for the records from Yili valley which could have some misleading conclusions of humid early Holocene.




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Changes in the vegetation of northern foothills of the Alborz Mountains, south of Aliabad, preliminary results of the pollen analysis of Tuska Tchal peat bog

Jacques-Louis de Beaulieu1, Morteza DJAMALI1, Philippe Ponel1, Habib Zare2

1: Institut Méditerranéen de Biodiversité et d’Ecologie (UMR CNRS – IRD – Aix-Marseille Université), France 2: Agricultural and Natural Resources Center of Mazandaran, Iran

Unlike the presence of the Caspian Sea that acts as a major

source of moisture that has caused the formation and maintenance of the mesophytic broad-leaved deciduous forest, “the Hyrcanian Forest”, Suitable lakes and peat bogs for palaeoecological investigations in the northern Alborz Mountains are very infrequent. In this study we present the first pollen diagram from the eastern section of the Alborz Mountains in a fragmented landscape composed of relict forest stands and pastoral and cultivated lands. A ~500 cm sediment core was taken by a Russian corer and provides an approximately 2050-year record of environmental change.

Pollen analysis of this core indicate a vegetation dynamics marked by the replacement of a Quercus forest by a Carpinus forest. Traces of human activities are evident all along the core and are characterized by agro-pastoralism (Plantago lanceolata-type pollen / dung-associated fungal spores) and arboricultural activities (Juglans, Vitis, and Platanus).


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“Hidden species” as part of the biodiversity in large lake basins: the case of the liverwort Riella in Lake Urmia

Morteza Djamali1, Lora Stevens2, Jacques-Louis de Beaulieu1, Philippe Ponel1, Valérie Andrieu-Ponel1

1: Institut Méditerranéen de Biodiversité et d’Ecologie (UMR CNRS – IRD – Aix-Marseille Université), France 2: California State University, USA

Both pollen and geochemical data attest to very large-scale lake

level changes in Lake Urmia during the late Pleistocene. Pollen/spore data of a long sediment core from this lake covering the last two glacial-interglacial cycles, reveal the relatively continuous presence of the liverwort Riella, a plant never recorded from the flora of Iran. However, this plant is thriving in many wetlands over the Iranian plateau and most probably in the surrounding regions of the Middle East and Central Asia. Riella provides us with an example of a sensitive part of the biodiversity that is hidden from the human eyes but very endangered by uncontrolled human interventions in the natural ecosystems. This hidden component of biodiversity has to be considered in the biological conservation and management of the wetlands.



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Dust storm, new phenomenon in Caspian Sea (Synoptic analysis of dust storm transition to Caspian Sea)

Maziar Gholami1, Maryam Abbasi2

1: PhD student of physical oceanography Physical oceanography Department, Science and Research branch of Islamic Azad University, Tehran, Iran (Meteorology expert of Gilan Meteorology Organization, Rasht, Gilan, Iran) 2: PhD student of Marine biology Marine biology Department, Science Faculty, Gilan University, Rasht, Iran

According to the World Meteorology Organization definition,

Dust storm and sand storm are ensembles of particles of dust or sand lifted to great heights by strong and turbulent wind. They occur mainly in arid and dry regions and can move to other regions by atmospheric flows and play a significant role in atmospheric and marine environments. Dust can alter the earth’s radiative balance by lofting considerable amounts of mineral aerosols into the atmosphere and can make some changes in marine ecosystem. They threaten lives and health in these environments and numerous observational and modeling studies have shown that dust storm have considerable influence on air and sea by affect on air temperatures, may cause ocean cooling and deposition, and alter rainfall amounts.

In this study we investigate the meteorological conditions that lead to the initiation of dust events and cause dust storm transfer to the Caspian Sea. For this purpose, we select eight case of dust storm that transfer to the Caspian Sea in recent two years (2011 and 2012). The main parameters used are several types of data and information that including synoptic maps (different levels from surface to 500hpa height), Radiosonde data, satellite images and NCEP Reanalysis gridded Climate Data that contains zonal and meridional component of wind, Geopotential height, Omega (rate of change of pressure in a parcel over time), sea level pressure. The method of the research is the synoptic approach.

Results shows that several factors are involved in the creation of the dust storms, but the main factors are circulation of the atmosphere in earth surface and upper level. Low pressure


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(especially dynamic low) and the vertical motion of air are the main causes of dust storms in the Middle East especially over arid and dry regions of Syria, Iraq and Saudi Arabia. Dust storm form and develop when a low pressure (about 1005hpa or lower) locate in south of Syria or over Iraq that create cyclonic circulation in earth surface. Also existence of a trough in upper level intensifies dust storm and vertical motion. This pattern causes that wind speed increase in surface and upper levels. After creation of the dust storm by surface and low level instability over Iraq and Syria, it extend over Iraq and move toward Iran because of shifting to the east due to the development of instability caused by the trough in upper level and northwest wind. Dust move from west to east in different levels (from surface to upper levels) and can pass from Zagros Mountain and enter center of Iran.

It is found that dust storm can transfer over Caspian Sea by two mechanisms. In first mechanism when a low pressure locate over Caspian Sea and high pressure in center of Iran, this pattern causes to form a south to north flow that force dust to move from center of Iran to the north. Dust particles can enter to Gilan plain and Caspian Sea through Sefidrood Valley (Manjil gap) in earth surface and can pass from Alborz Mountain and enter to Gilan plain and Caspian Sea by upper level trough. This pattern is seen in some selected cases and synoptic station of Gilan meteorology organization reported dust storm with low visibility and also satellite images showed this intrusion. This mechanism usually accompany with foehn effect and warm wind (south wind) that Radiosonde data confirm this results. Six cases follow first pattern.

In second mechanism, when high pressure extend in earth surface and ridge (stability) dominate in upper levels over Caspian Sea (Gilan plain) and most of Iran, therefore dust (that formed and intensified over Iraq or south of Syria) cannot spreads to central part of Iran. It moves toward northwest of Iran, Turkey and Azerbaijan by upper level wave (500hpa) and finally shifting to the east and over Caspian Sea and move with trough from higher latitude. Location of trough axis, region of upper level divergence, especially in 500hpa and formation of low pressure and position of other air masses at earth surface have major role in formation, dispersion and transmission of dust. Two cases follow the second pattern.




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The Ways for Constant and Episodic Underground Connection the Aral and Caspian Seas in the Paleogene and Neogene Sediments of the Ustyurt Plateau

B. N. Golubov1, V.G. Pronin2

1: Institute for Dynamics of Geospheres and Institute of Oceanology. Russian Academy of Sciences. Moscow. Russia. 2: Federal State Unitary Scientific-Production Institution «AEROGEOLOGIYA». Moscow. Russia.

The idea of underground channels between the Aral and Caspian

seas was first suggested about 933 by the Arab traveller and geographer Al-Istakhri. Scientific statement of that question was formulated by the B.N. Golubov in 1982-1995 and confirmed by N.A. Shilo and M.I. Krivoshey (1989), I. V. Kononov (1993), M.M Alklychev (2000).

The objective of report is to develop this idea and show structural and historic-geological conditions for the formation of two mechanisms of underground hydraulic connection of the Aral and Caspian seas: continuous and episodic. The work is based on the results of many years marine and land geological, geophysical, hydrogeological and drilling works in the Aral-Caspian region.

The history of development these mechanisms may be divided on three stages. The first of these appeared in the Pliocene during Pre-Akchagyl time in connection with sharp deformations the Earth's crust and formation giant morphstructure named as the Aral-Caspian area of neotectonic depression. Now that depression is covered by Pliocene-Quaternary deposits which overlap with sharp angular and asimutal disconformity the different structural floors of ancient East European platform, the young Scythian-Turan plate and Caucasus-Alborz-Kopetdag segment of the Alpine folding. Under this cover and partially in his body are laying number of sedimentary oil-bearing artesian basins that content enormous volume of free underground water, which is ten times larger than the volume of the Aral and Caspian Sea.


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At the second stage in that giant morphostructure were formed the most submerged Caspian Sea neotectonic depression and elevated Board zone. In the eastern part of Board zone was arised the Aral Sea dry erosion depression. Beside it numerous water-bearing Paleogene and more ancient horizons of artesian basins were inclined to the Caspian Sea, which has become a constant discharge of groundwater flow concentrated not only in the same gravity-convection hydrogeological systems but also in the elision, closed compression and hydrothermal fluid-dynamic systems.

The third stage was connected with the development karst caves on the upper Miocene carbonate deposits on the Ustyurt Plateau in Pliocen-Quaternary time. As result water and fauna of the Caspian Sea during his most extensive Akchagyl, Apsheron and maybe Hvalynian transgressions sometimes penetrated by karstic and porous space in the Aral depression and mixed with surface water flows drained from the Pamir and Tianshan mountains along the Pra-Amudarya and Pra-Surdarya rivers.

Therefore interact fluctuations of the Aral and Caspian Sea levels regulated in the Pliocene-Quaternary and modern time not only by climate but also by underground hydrosphere.



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Molecular and Isotopic Evidence for Prehistoric Subsistence Practices Associated with the Earliest Uses of Ceramic Technologies in the Caspian Basin

Michael W. Gregg1, Greg. F. Slater2

1: Environmental Organic Geochemistry Group 2: School of Geography and Earth Sciences, McMaster University

Compound-specific isotopic analysis of organic residues

surviving in fired-clay and pottery fragments from late Pleistocene and early Holocene human occupations of Hotu and Belt caves in northern Iran has revealed δ13C values consistent with those of modern carcass fats of sheep, goats, cattle and pigs and ruminant milk fats. Coupled with faunal evidence, these results demonstrate that clay was used in cooking meats from wild ruminant species at the onset of the Holocene circa 12000 BP and pottery vessels were used in cooking meats and processing milk by the late Neolithic period. This is the earliest direct evidence for the use of ceramic technologies in cooking observed to date.

Human skeletal remains recovered from Mesolithic and Neolithic levels at Hotu and Belt caves are also currently being examined at the Smurfit Institute of Genetics at Trinity College Dublin and the Research Laboratory for Archaeology at the University of Oxford. These remains are uniquely placed to clarify the phylogenetic relationship of late Pleistocene hunting and gathering groups in western central Asia and agropastoral populations originating in the Middle East.

Findings from these studies raise many questions about core and peripheral areas of independent economic innovation in western Central Asia, and draw attention to the necessity of further research into the role of ceramic technologies as a catalyst for mobile and sedentary ways of life in the Caucasus, Golestan and Transcaspian regions. And perhaps even more importantly — the compelling need for detailed reconstruction of the effects of climatic variability on vegetation and faunal distributions and human dispersals associated with late Pleistocene and early Holocene transgressions and regressions of the Caspian Sea.

Email: [email protected] Email: [email protected]


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Geological and Geographical similar ities between the Lake Tuz and Lake Urmia basins: Implications for their Quaternary evolutions

Alper Gürbüz1, Nizamettin Kazanci2, Moosarreza Toori2

1: Niğde Üniversitesi, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, 51100 Niğde/Turkey 2: Ankara Üniversitesi, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, 06100 Ankara/Turkey

Lake Tuz of Turkey and Lake Urmia of Iran represent amazing

similarities on their geological and geographical features. They are located within large closed drainage basins and geologies of those basins represent very similar lithologies and tectonic origin and control mechanisms. Spatial and temporal variations of geologic units gained approximately same physical and chemical characteristics to the lakes. These lakes are two of the largest hypersaline lakes in the world. Geographically, both lake basins are situated about the same altitudes and between the same latitudes. Understanding some of these features for one of these lake basins could reveal valuable informations for the further. In this study, we compare the geologic and geomorphic characteristics of the Lake Tuz and Lake Urmia basins to interpret their evolutions and reveal the glacial-interglacial variations in rainfall and streamflow along the Turkish-Iranian plateau in the Quaternary period.




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Distr ibution and relevance of sand sediments in organic-enr iched lagoons, South-West of the Caspian Sea, Sefidrud River Delta S. Haghani, S.A.G. Leroy Institute for the environment, Brunel University, Kingston Lane, UB8 3PH, Uxbridge, London, UK

The Sefidrud delta has developed in the south west Caspian Sea

and it is formed by the River Sefidrud, which is the largest sediment source for the Caspian Sea. Its peculiarities are very rapid sedimentations rates and a very steep slope setting. It can be used as a model for oil-bearing reservoirs in steep slope delta settings. This study aims to explain the evolution of the Sefidrud delta and a mechanism for delta building will be proposed.

In the present study, we aim at assessing the relationships between the distribution of sediments and the amount of magnetic susceptibility on short sediment cores taken in three lagoon systems, Amirkola, Zibakenar and Kiashahr Lagoon, associated with the Sefidrud delta. For this purpose, we correlated the sediment cores inside each basin based on magnetic susceptibility values, particle size of sediments as well as colour change based on visual description. With a chronological framework, this correlation can be used to reconstruct historical changes in sedimentation and consequently, a sediment distribution pattern can be obtained.

In general, the Amirkola lagoon showed a clear-cut change at around the same depth, i.e. 40-60 cm, in the magnetic susceptibility values, which is obviously matched with the sand layer in the central part of lagoon. This high amount of magnetic susceptibility can be related to magnetite and ilmenite that are supplied by the Sefidrud (Lahijan & Tavakoli, 2012). The presence of marine shells in this sand layer in the middle part of lagoon shows that the source should be the sea that either invaded the lagoon as wash over fan or the location was under the sea during a period of higher sea level. Indeed Leroy et al. (2011) have shown in a core taken from the north east of the lagoon, that the sand was marine and dated from the late Little

http://www.sciencedirect.com/science/article/pii/S0025326X07004614�

http://www.sciencedirect.com/science/article/pii/S0025326X07004614�


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Ice Age, a period of high stand. The present study shows now the horizontal extension of this sand layer. Magnetic susceptibility in mud layer in the southern part of lagoon shows an enhancement, compared with mud layer in the north part, which can be interpreted as a change in source of clay in this part of basin. Large changes in lagoonal morphology were caused by human-induced dredging of channels, in order to use the water for the rice paddies surrounding the lagoon. The mud accumulation in Kiashahr lagoon also can be a result of dredging made in order to change land use from fishing port to commercial port, in 2010. The lack of sand layer in the Zibakenar Lagoon represents a low energy environment in which the lagoon has not been subjected to human impact.



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Middle to Late Holocene climate var iations in central Tienshan Mountains, central Asia Xiaozhong HUANG*, Chunzhu CHEN, Fahu CHEN MOE Key Laboratory of West China's Environmental System; Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou 730000, China

We present palynological records and discuss about pollen-based

past vegetation and climate changes from core BY10A in Lake Meitiane, an alpine lake situated at an intermontane basin in the central Tienshan Mountains, northwestern China. Modern surface pollen analysis was used to help interpret fossil pollen data which provided information of vegetation history since the last 8.5 ka. Combining the analysis of modern and fossil pollen as well as chronology, we preliminary infer past vegetation and climate evolution in Lake Meitiane area as follows: at 8.5-6.8 ka, the local vegetation was steppe meadow suggesting a cool and slightly wet climate; at 6.8-2.6 ka, alpine meadow dominated the landscape at Lake Meitiane with peat accumulation but interrupted by an interval of alpine steppe with some aquatic pollen at 5.5-4.5 ka, indicating a generally warm and moderate (some dry) climate interrupted by a short-term cool and humid period; at 2.6-0 ka, lake water came back and steppe meadow regained dominance, which demonstrated a warming trend with increasing humidity. The paleovegetation and paleoclimate variations reconstructed from Lake Meitiane showed possibly different patterns with those from adjacent areas with lower elevation, indicating that they are possibly influenced by different forcing mechanism.




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Oil seeps in the Caspian Sea seen from space in synthetic aper ture radar images

Andrei Yu. Ivanov P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences Nakhimovsky prospect 36, Moscow, 117997, Russia

One of well-known features of the Caspian Sea is hydrocarbon

seepage. Marine seeps emit ground waters, oils and gases, including methane. There are several active seepage fields especially in the south-west (SW) section of the sea. Estimating the number and amount of natural seepage of crude oil into the sea is very important task. In the end, hydrocarbon seeps themselves, can be considered as the supplier of the Caspian Sea by gases and oils, and their intensity and rates as an indicator of the environmental changes. Their contribution to the marine environment has to be better established and estimated.

In the last years seeps have been intensely studied by using conventional and remote sensing methods. To understand their behavior and spatial-temporal characteristics many synthetic aperture radar (SAR) images acquired by SAR-equipped satellites, such as the European ERS-1, ERS-2 & Envisat and the Canadian Radarsat-1 & Radarsat-2 satellites, were collected. The image analysis allowed identifying several sites, where natural oil seepage occurs. The most pronounced oil slicks with high persistency of floating oil were found over the structures in the Iranian and Azerbaijani sections.

In present study the oil seeps are studied with use of SAR imagery and geo-information approach, when all oil slicks visible on the SAR images of the sea surface are collected in geographic information system (GIS). In particular, GIS integrating the vector contours of oil slicks from the SAR images, the nautical maps and other additional & complementary data (bathymetry, geology, geophysics, oil &gas infrastructure objects etc.). This, first, allows revealing a relationship of detected oil slicks with the seafloor sources, and, second, estimating seep rates. Using this approach the oil seeps in the SW Caspian Sea as well as recent activation of


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shallow seeps in the Northern Caspian Sea have been documented, studied and estimated.

As revealed the hydrocarbon sources located on the sea floor at depths from 10-20 to 500-700 m. Based on analysis of the slick’ areas, seep rate can reach up to thousands - ten thousands metric tones of crude oil per year. This means that seepage is the main source of natural “oil pollution” in the Caspian Sea, and requires getting more exploration attention. Importance of understanding of natural oil seeps in the context of environmental aspects and global changes is discussed.



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Ground penetrating radar studies along the present and past coastlines of large lake basins

H.M. JOL, W. L. LOOPE, D.G. SMITH, T.G. FISHER, L. J. MOORE, P. REEDER 1: Department of Geography and Anthropology, University of Wisconsin Eau Claire 2: United States Geological Survey 3: Department of Geography & Earth Science Program, University of Calgary 4: Department of Environmental Sciences, University of Toledo 5: Department of Geological Sciences, University of North Carolina at Chapel Hill 6: Department of Geography, Environment and Planning, University of South Florida

Ground penetrating radar (GPR) provides a methodology that

enables one to image the subsurface stratigraphy of many geomorphic environments, including coastal settings. GPR studies conducted along the present and past shorelines of large lake basins have provided detailed subsurface stratigraphic information that have aided in better understanding lake history. The Great Lakes contains one of the greatest concentrations of coastal depositional features in the world. This paper presents a summary of results from GPR studies conducted along modern and past coastlines of the Great Lakes including Lake Eric, Lake Michigan, Lake Ontario and Lake Superior.

GPR is an electromagnetic geophysical tool that enables one to image (2D & 3D) the subsurface stratigraphy of coastal environments in a continuous, non-destructive, and non-invasive manner. The GPR acquisition systems used for the study were pulseEKKO 100 & 1000 with antennae frequencies ranging from 50 MHz to 900 MHz and transmitter voltages ranging from 200 volt to 1000 volt. Often coastal studies are conducted using lower frequency antennae (50-100 MHz) to better understand the complex stratigraphy that is revealed. As our understanding of coastal depositional systems in large lake basins improves, higher frequency antennae (200 - 900


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MHz) are being utilitized to provide a more detailed image of the subsurface layers. Step sizes and antennae separation varied depending on antennae frequency chosen and on the site conditions. The digital profiles were processed and plotted using pulseEKKO software. Depths of deposits were calculated using near surface velocity measurements from collected common midpoints.

Radar stratigraphic analysis on the collected data provided the framework to investigate both lateral and vertical geometry and stratigraphy of the coastal deposits. GPR profiles, with depths of penetration greater than 30 m, reveal patterns showing coastal growth by aggradation and/or progradation as well as features showing coastal erosion. Interpretations of the results suggest that several different coastal processes are at work within the Great Lakes including longshore transport, changes in sediment supply, and response to lake level changes.



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Late Pleistocene and Holocene sea-level change and coastal palaeoenvironment evolution along the Iranian Caspian shore

Kakroodi, A.A.1, Leroy, S.A.G.2, Kroonenberg S.B.1, Lahijani H.A.K.3, Alimohammadian, H.4, Yamani. M.5, Nohegar, A.6 1: Delft University of Technology, Faculty of Civil Engineering and Geosciences, Department of Geotechnology 2: Institute for the Environment, Brunel University, Uxbridge UB8 3PH, London, UK 3: Iranian National Institute for Oceanography (INIO), No.3, Etamadzadeh St., Fatemi Avenue., Tehran 1411813389, Iran 4: Geological Survey of Iran, Tehran, Iran 5: Department of Physical Geography, Faculty of Geography, University of Tehran, Tehran, Iran 6: Department of Rangeland and Watershed Management, Faculty of Agricultural Sciences and Natural Resources, Hormozgan University, Iran

A Late Pleistocene to Holocene Caspian sea level record has been

reconstructed by a multi-disciplinary approach from a 27.7 m long core in the SE corner of the Iranian Caspian coast in the Gomishan Lagoon. Late Pleistocene deposits containing typical Pleistocene fauna and dated around 20,100 cal. yr BP end up in a major hiatus indicating sea-level fall. Lagoonal deposits with shells dated at around 10,500 cal. yr BP suggest that, after this deep lowstand, an initial transgression started, leading to landward advance of barrier-lagoon systems. Increasing accommodation space led to changes in biofacies depth and the development of modern fauna including diatom and Gastropoda species. Around 8400 cal. yr BP sea level started to fall again, and reddish oxidized sediments with abundant foraminifera (Ammonia beccarii) record a regressive phase around 7700 cal. yr BP. The mid-Holocene is characterized by a shallow marine environment mostly with high carbonate and gypsum content, lagoonal and highstand tract with no subaerial facies. The upper part of the core above 4.9 m depth reflects at least five Late Holocene Caspian Sea sea-level cycles from 3200 cal. yr BP onward.




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Application of cladoceran proxy for reconstructing lake-level changes and development of an ecological and socio-economic framework for adaptation

Giri Kattel

School of Science, Information Technology and Engineering, University of Ballarat, Ballarat, Australia & School of Architecture and Building, Deakin University, Waterfront Campus, Geelong, Australia

The large lakes across the globe are ecologically diverse freshwater

systems. Over the history of mankind, these lakes have become a fundamental source of ecosystem services including drinking water, irrigation and food supply. The large lakes situated across the Caspian Sea region, in particular, have considerable significance as the human settlement across the region goes as far back as the Late Pleistocene and early Holocene periods and the human connections to these lakes through land-use, transportation, fisheries as well as hunter-gatherer activities have been reflected by sedimentary remains. There were abrupt shifts in ecosystems and socio-economies of the people in the region. However, the level of intensity of disturbances in ecosystem structure, functions and services is not comprehensively examined. Identifying the links between the potential drivers, stressors and ecosystem responses of large lakes are crucial for future adaptation of mankind to climate change in the region. The use of multi-proxy approach provides reliably accurate information on ecological regime shifts in large lakes in the past. The cladoceran zooplankton, a small group of branchiopod crustaceans, plays a significant role in food web dynamics in lakes. They are sensitive to large and small scale shocks including climate change and human-induced disturbances. Following their death, the head shield, carapace, post-abdomen and ephippia of both planktonic and littoral cladocerans are preserved well in lake sediment, and have indicated that during the last glacial-interglacial and the Holocene periods, they have adapted to varying shocks in ecosystems. For example, Bosmina continued to adapt to warm


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interglacial phases while the diversity and populations of chydorids became high during the last glacial cold period. However, the use of cladoceran proxies to understand the history of changes in climates, lake levels and human disturbances of the Caspian Sea region is rare. In this paper, I would like to provide the usefulness of the cladoceran proxy to reconstruct past lake level changes, and propose an ecological and socio-economic framework for adaptations to climate change in the Caspian Sea region during the twenty first century.




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Late Pleistocene-Holocene fan deltas of the Lake Burdur, Turkey; sedimentary records for rapid water-level changes

Nizamettin Kazanci

Geological Engineering, Department, Faculty of Engineering, University of Ankara, 06100 Tandoğan, Ankara

A fan delta is formed by progradation of an alluvial fan into a

standing water, lake or sea. In this development, alluvial fan forms the subaerial delta plain of the fan delta. Together with some similarities to stream deltas, delta front facies of fan deltas are much more coarse-grained relatively. However, lacustrine fan deltas seem to be more complex as lakes are very sensitive to environmental changes. Lake Burdur located at southwest-central Anatolia provides good examples of the fan delta-delta formations. This lake is one of the closed water in Turkey, ca 140 km2 and 65 m deep. It occupies a NE-SW trending active graben. Water level of the lake which is presently at 846 m has been fluctuated due to both climatic and tectonic reasons at least since late Pliocene, forming various sedimentary facies. Four active alluvial fans and fan-delta complexes are prominent features in the northern lake margins, while there are three similar occurrences at the southern margins. Latter are not active now because of anthropogenic reasons. However, all have been mining heavily. Two of the fan-delta complexes at the northern margins, the Kocadere and the Soganli fan-deltas have been re-visited in order to detect long duration water levels in the lake history. Each deltaic complex consists of two fan-delta sequences interlayered by three alluvial-fan sequences. The oldest deltaic deposits and associated wave-cut terrace at the Soganli fan delta are placed at 980-960 m. They are at 960-940 m in the Kocadere complex, apart from deltaic formations and wave-cut terraces at 920-910 and 890-880 m elevations. The older delta-front and prodelta deposits of two complexes contain abundant fresh-water forms of Dreissena sp and Gastropoda, while the younger sequences includ


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brackish and saline forms of the same fossils. This was a typical record that Lake Burdur became a closed water after the latest Pleistocene-early Holocene time. Before it was fresh-water or open-lake for a long time period. From here it is possible to say that lake Burdur was connected to other central Anatolian lakes during glacial times. Now the efforts are to find time limits of the paleogeographic evolution.




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Dating Caspian Sea Level Change: Results of Project IGCP-481 Salomon B. Kroonenberg

Delft University of Technology, the Netherlands

The Caspian Sea, a closed basin with a sea-level regime of its own,

experiences sea-level oscillations in tidal, seasonal, decadal, centennial/millennial and glacial/interglacial time scales, each with different forcing mechanisms. The interference of these time scales hampers forecasts solely on the base of the instrumental record since 1834. Moreover, so far it has not been clear whether sea-level change in the Caspian follows the pace of global climate change, or behaves independently or even chaotically.

We improved therefore the data base of the past in the framework of IGCP 481 Dating Caspian Sea Level Change. We studied coastal processes during the last three-metres sea-level cycle between 1929 and 1995 in order to find the best sites for dating Holocene sea-level cycles. Holocene highstands were AMS-dated in Dagestan on in situ mollusks from lagoonal deposits overridden by highstand barriers, now perched above the present -27 m sea-level. Similar data were obtained from the southern Caspian coast in Iran. Transgressive phases were dated in the ramp delta of the Volga river in Russia, which, as has been shown during the 20th century sea-level cycle, progrades along the ramp during regressions, but aggrades vertically during transgressions. Lowstands were dated in corings through unconformities discovered during seismic surveys offshore the Kura delta in Azerbaijan.

Dating and palynological, malacological, and organic and inorganic geochemical data suggest at least the following events

(1) a Late Glacial (“Early Khvalyn”) +50 m highstand, with deposition in the deepest part of the South Caspian, in the


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Kura delta, and in the Gomishan area in Iran of reddish-brown clays similar to coeval deposits in the Black Sea;

(2) a deep regression (“Mangyshlak”) to at least -92m at the Pleistocene-Holocene transition;

(3) a prominent highstand at -22 m correlating with the ~2600 BP climate deterioration at the start of the Subatlantic;

(4) a -48m lowstand in the Warm Mediaeval Period and (5) a -25m Little Ice Age highstand. Precipitation changes in the Volga basin coinciding with major

Holocene climatic cycles are the main forcing mechanisms that explain rapid Caspian Sea level change.



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Holocene vegetation history and sea level changes in the SE corner of the Caspian Sea

Suzanne A. G. Leroy1, Ata A. Kakroodi2, Salomon Kroonenberg2, Hamid K. Lahijani3

1: Institute for the Environment, Brunel University, Kingston lane, Uxbridge UB8 3PH (London), UK 2: Department of Geotechnology, Delft University of Technology, The Netherlands 3: Iranian National Institute for Oceanography (INIO), No. 3 Etamadzadeh St, Fatemi Avenue, Tehran 1411813389, Iran

The palynological investigation of core TM (27.7 m long) reveals

Holocene vegetation history at the NE foothill of the Alborz Mountains and water level changes of the Caspian Sea.

The delay in woodland expansion at the beginning of the Holocene, which is typical of eastern Turkey, the Iranian plateau and recorded in the CS south basin, is only weakly felt in the region as it is close to glacial refugia of trees.

The succession of the main trees out of their refugia has been established as deciduous Quercus, Carpinus betulus, Parrotia persica, and Fagus orientalis-Pterocarya fraxinifolia, presenting therefore close affinities to south European interglacials of the Early Pleistocene.

A Pterocarya decline is observed after AD 315. The studied region is close to the tree easternmost distribution; this could explain why it has been affected earlier than elsewhere in the northern Alborz and the Caucasus. In addition human activities during the Sasanian Empire and the subsequent drying of the climate may have contributed to weaken the spread of this tree.

A maximum sea level occurs in the first part of the Holocene at 10.6-7 ka. It is suggested that the CS levels were significantly influenced by the monsoon precipitations over the western Himalayas. This is followed by low levels at 7-3.5 ka.

Finally it is recommended that the Neocaspian should be considered a biozone rather than a chronozone as the environmental conditions reconstructed from dinocyst assemblages are different in shallow shelf waters than in the deep basins of the Caspian Sea.




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The magnetic susceptibility behavior along two cores in Hassangholi Bay, eastern flank of the Caspian Sea and their interpretation for the sea level changes

Naderi Beni, A.1, Mousavi Harami, R.1, Lahijani, H.2, Mahbnoobi, A.1

1: Geology group of Ferdowsi University of Mashhad 2: Marine geology group of the Iranian National Institute for Oceanography

Magnetic susceptibility is largely depending to mineralogy of

materials particularly to Fe- bearing minerals. However, some other inherent and non-inherent properties of sediments such as grain size and shape can impact the measures. This property enables us to classify different types of sediments based on their magnetic behavior.

The Hassangholi Bay lies in the eastern flank of the Caspian Sea where the region has been influenced by the level changes. The area receives sediments from different sources with different magnetic properties. Copet Dagh in the east is the main source for detrital carbonate while Alborz Mountain in south could be the main source for Fe bearing minerals. However, the Caspian Sea could bring sediments during sea level rise. This last source could change the magnetic susceptibility behavior of the sediments and could be a potential proxy for tracing the Caspian Sea level fluctuations.

This paper tries to make a correlation between the magnetic susceptibility and sea level curves in the eastern flank of the Caspian Sea.



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Late Little Ice Age highstand in the Caspian Sea and its impacts on the morphology of Sefidrud Delta in central Gilan

Naderi Beni, A.1; Lahijani, H.2; Mousavi Harami, R.1; Leroy, S.A.G3

1: Geology group, Science Faculty, Ferdowsi University of Mashhad 2: Marine geology department, Non-living sciences group, Iranian National Institute of Oceanography 3: Brunel University

Introduction The morphology of two Kiashahr, in west and Amirkola lagoons,

in east, along the eastern flank of Sefidrud Delta has been investigated regarding to sea-level changes since the Late Little Ice Age. Generally the Caspian Sea level were high during the Little Ice Age ( Leroy et al., 2011). This research focuses on this highstand and its impacts on the morphology of the Sefidrud Delta. Method

Two-dimensional Ground Penetrating Radar (GPR) have been carried out along 4 transects normal to the coastline using an unshielded RAMAC/GPR system. The mean frequencies of 50 and 100 MHz have been selected for the antenna to provide a good trade off between depth penetration and resolution. Three cores were taken by a vibracorer system and the sub-samples were examined to get basic sedimentological results including organic matter content, carbonate content and grain size. Organic matter and carbonate content have been calculated based on Heiri et al. (2001) outlined methods. Fritsch standard sieve stack was used for getting grain-size results. Two beach profiles have been measured along the GPR transects perpendicular to shoreline using a Total Station. The results were used in GPR data processing and surface morphology reconnaissance studies. A bulk organic matter and a wood sample have been selected and sent to Poznan Radiocarbon Laboratory for radiocarbon dating. Results and discussion


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Beach profiles show different profiles for Amirkola and Kiashahr beaches. The beach sediment is composed of medium sand fraction containing heavy minerals which is an evidence of storm deposits (Buynevich et al., 2004; Dougherty et al., 200; Lindhorst et al., 2008). However, the heavy mineral content in the Amirkola Spit is sizably lower than that in Kiashahr Spit.

According to GPR profiles three different main facies could be distinguished in Kiashahr Spit including marine (shoreface and beach ridge facies), Fluviodeltaic and aeolian facies. In Amirkola Spit also three types of radar reflectors were distinguished including delta plain, lagoon and aeolian facies. All of the radar interpretations are supported by sedimentological evidences.

Dating results show that the base of the fluviodeltaic sediments in Kiashahr Spit has an age of AD 1696 to 1726 which could be considered as the changing the course of the old Sefidrud River to its present position.

According to the GPR measurements and sedimentological investigation it seems that the Sefidrud Delta is an asymmetric delta (Weiguo et al., 2011). Before the river avulsion, the morphology and facies of Kishahr show the updrift side properties including shoreface and beach ridge deposits; while Amirkola was in the downdrift side and shows lagoon and delta plain deposits. When Sefidrud shifted to west to the present position between AD 1696 to AD 1726 , the old facies covered by new fluviodeltaic deposits and both of the lagoons felt in the downdrift side of the present delta. Conclusion

The Sefidrud River is an asymmetric delta influenced by west littoral drift of the Caspian Sea. During the Late little Ice Age, when the Caspian Sea experienced highstand, the Sifidrud River changed its course from east to west. It seems that the river avulsion is a consequence of the sea level change.



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Title: Trophic status of Caspian Sea based on environmental parameters and phytoplankton diversity dur ing Nodular ia spumigena bloom event and Mnemiopsis leidyi Invasion

Dr. Hasan Nasrollahzadeh Saravi*, Asieh Makhlough, Reza Pourgholam Caspian Sea Ecology Research Center (CSERC)

This talk was conducted to investigate the environmental

parameters and biological data of the southern Caspian Sea (CS) during two phases, Phase 1 (1996-97) and Phase 2 (2005). The invasion of the southern Caspian Sea by the alien species (Mnemiopsis leidyi) occurred between the two phases and Nodularia spumigena bloom event happened in summertime of 2005.

The status of the marine coastal waters of the southern Caspian Sea was assessed using the TRIXCS, OECD, EEA and other indicators in line with the use of other biological indicators (e.g. the Shannon–Weaver index). Nutrient concentrations (DIN, DIP), Chl-a and aD%O for both periods and for the Parallel Study differed significantly (p<0.01) with higher values recorded after the introduction of an alien species. The data also show that the phytoplankton community structure has changed significantly some species have disappeared and others have become dominant.

The Shannon–Weaver index was found to be higher during Phase II (after the introduction of an alien species) as compared to Phase I (before the introduction of an alien species). Although the various indices and indicators used to classify the trophic status of the Iranian coastal waters of the CS did not always achieve the same trophic status, but an overall analysis of the water parameters and biological factor pointed out to a high to good status for Phase I and moderate status for Phase II. It can be seen that the present situation in the CS is quite similar to that of the Black Sea (during the introduction of the ctenophore M. leidyi in the 1980s), with the appearance of this alien species which can be considered as a form of ‘‘biological contamination’’.

Previous studies have announced the bloom-forming Cyanophyta Nodularia spumigena Mertens to the Caspian Sea. In this talk, I attempt to understand the bloom events that are involved Nodularia spumigena population and environmental parameters in the Iranian


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coastal water. The preliminary results suggested that Nodularia spumigena observed in the Caspian Sea in some seasons at different depths but bloom formation starting from middle of summer and reach a maximum in the early of autumn at the surface. Result of this research showed that phytoplankton assemblage comprised of 46 species after bloom. Bacillariophyta had the highest number of species (17) follow by Pyrrophyta (14), Cyanophyta and Chlorophyta (6) and Euglenophyta (3). But, phytoplankton species of bloom sample is classified in three groups: Cyanophyta, Pyrrophyta and Bacillariophyta which Cyanophyta dominated over the other groups of algae and formed more than 98% and 96% of phytoplankton abundance and biomass, respectively.

As of now, the pattern of dominant and frequent species in the Caspian Sea indicated that the health of the water body and aquatic organisms are at risk. Biography

Hasan Nasrollahzadeh Saravi, male, Environmental biologist, graduated at PhD program from biology faculty, University Science Malaysia (USM) in 2008, He works in a Research center since 1993, Caspian Sea Ecology Research Center (CSERC), now he is deputy of its Company since 2010. His scope is regarding Ecology and Pollution. From 1993-2003, he worked in CSERC as a head of chemistry department, From 2008-2010, he was as a head of biology department, He published 25 international and ISI papers, Now he has published more than 100 papers at national and international conferences. In addition to the National Outstanding Contributor and some awards to him was for the science success. He was selected as an academician of Iranian Academy of Sciences in 2010 and 2012. He involved in 54 research projects as a manager and co-worker regarding Ecology, Pollution at Ponds, Rivers, lagoon and the Caspian Sea. He is a part time lecturer at a university regarding Ecology, Limnology and pollution courses. He supervised more than 20 students as a supervisor and co-supervisor at M.Sc. and PhD program.



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The effects of the current system of Beyşehir Lake (TURKEY) on the physical and chemical parameters of water quality

Emin Ender ÇELEBİ1, Zeynep ERGÜN2, Klaus ARPE3, Suzanne A.G. LEROY4, Nizamettin KAZANCI5, Özden İLERİ5, Güleda ENGİN6, Mehmet Salim ÖNCEL1*

1: Department of Environmental Engineering, Engineering Faculty, Gebze Institute of Technology, 41400 Gebze, Kocaeli, Turkey 2: Department of Geological Engineering, Faculty of Engineering, Ankara University 06100 Besevler, Ankara, Turkey 3: Max Planck Institute for Meteorology, Bundesstr. 53, D-20146 Hamburg, Germany 4: Institute for the Environment, Brunel University, UB8 3PH Uxbridge, UK 5: Geology Department of General Directorate of Mineral Research and Exploration, 06520, Ankara, Turkey 6: Department of Environmental Engineering, Faculty of Civil Engineering Yildiz Technical University, 34220 Davutpasa, Esenler, Istanbul, Turkey

Beysehir Lake, one of the important wetlands of Turkey, is heavily

influenced by anthropogenic pollution sources arising from residential and agricultural areas. The study area is located administratively within the boundaries of 2 different cities namely, Konya and Isparta. The water level is maximum 1125.50 m. It is the 3rd largest lake in Turkey following Van Lake (brackish lake) and Salt Lake (saline lake) and the largest freshwater lake and drinking water reservoir in Turkey. It has a length of 45 km and width of 26 km at the widest point. The settlements are 2 major towns (municipalities) with a total population of 61 196, other 36 smaller municipalities with a total population of 125 562 and 68 rural settlements (villages) with a total population of 22 237 according to 2008 general census.

In the study, the aim was to assess the impacts of the current system of the Beysehir lake as a drinking water reservoir. Water samples and measurements were taken from 45 stations in Lake Beysehir between July and August 2012. Current direction and speed, water depth, water temperature, pH, Secchi depth, conductivity and dissolved oxygen


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parameters were collected. Current direction and speed values were found between 3.55-46.98 cm/sn and 41.47-322.78 degree. Water depth was measured between 4-10.20 m at the sampling points. pH varied between 8.04 and 8.95. Secchi depth was measured between 1.10-3.30 m. The average conductivity values were 365 mg/L. The dissolved oxygen values were found between 7.35 and 8.47 mg/l. The water temperature changed between 26.21 0C and 33 0C.

Based on the data, it is apparent that the flow system in Beyşehir Lake directly affects the physical and chemical water quality parameters. In addition, variations in both magnitude and directions of stream lines suggest the existence of other water inflow and outflow points. The flow system in Beysehir Lake likely controls the particle size and the thickness of the current sediment in the bottom of the lake.



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A record of Late Quaternary continental weather ing in the sediment of the Caspian Sea: evidence from U-Th, Sr and Li isotopes, trace element and palynological data

Pierret Marie-Claire1*, Chabaux François1; Leroy Suzanne A.G.2

1: Laboratoire d’Hydrologie et de Géochimie de la Surface (LHyGeS), EOST, Université de Strasbourg et CNRS 1, rue Blessig 67 084 Strasbourg - France 2: Institute for the Environment, Brunel University, Kingston Lane, Uxbridge UB8 3PH, West London - UK

This study presents combined mineralogical, chemical, isotopic

(87Sr/86Sr, Li and U-Th disequilibria series) and palynological analyses on bulk sediments and on distinct mineral phases (carbonates and clays) from a 10-m-long core drilled in the southern Caspian Sea and containing a Late Pleistocene and Early Holocene record.

The data allowed identifying 1) the main variations in sedimentation, 2) the processes causing these variations, 3) the modification of erosion vs weathering, and 4) the influence of climatic and/or Caspian Sea level changes in the region since the Late Pleistocene.

The chemical and mineralogical results allowed the division of the sedimentary sequence into three main units and a transition zone. The lower unit (unit U1) primarily consists of silicate and carbonate-rich detritus. Sedimentation characteristics, including observation of detritus in secular equilibrium, are relatively constant within this unit and reflect mechanical erosion in a cold climate. Unit U1 probably corresponds to a glacial period when the vegetation cover was sparse and wind and river transport of pollen were strong.

Subsequently, global increase in temperatures has greatly modified the sedimentation in the Caspian Sea south basin. Biogenic sedimentation is higher in units U2 and U3, and detrital inputs varied from unit U1. Variations in detrital input are likely to be caused by decreasing aeolian contribution and by relative changes in river volumes and origins. The study of the bulk sediments, clays and carbonates reflects an increase in chemical weathering since about 10 14C ka BP ago (base of unit U2), in line with an increase in the vegetation cover.


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Our results suggest an evolution of continental weathering conditions in the catchment area of the Caspian Sea, from dominantly mechanical/physical erosion during the cold period to a continuous increase in weathering since the Lateglacial period, as climate improved, which illustrates the strong relation between climate, vegetation cover and weathering processes. This paper also highlights how the U-Th disequilibrium series proxy, combined with other geochemical and palynological studies, could be a useful tool to record and constrain the modification of weathering regime in response to climatic and environmental changes at regional scale.



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A High-resolution Record of Holocene Climate Var iability From Neor Lake in NW Iran: Investigating the Role of Abrupt Climate Change on Human Civilizations in West Asia

Sharifi, O.1, Pourmand, A.1*, Canuel, E. A.2, Peterson, L. C.1, Djamali, M.3, Lahijani, h.4, Naderi, M.4

1: Division of Marine Geology and Geophysics, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA 2: Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, VA, USA 3: Institut Méditerranéen d'Ecologie et de Paléoécologie UMR CNRS 6116 - Europôle Méditerranéen de I'Arbois – Pavillon Villemin - BP 80, 13545 Aix-en-Provence Cedex 04, France 4: Iranian National Institute for Oceanography (INIO), No.30 Etemad Zadeh St., West Fatemi Ave, 14155-4781 Tehran, Iran

New observations of enhanced melting at the margins of the

Antarctic and Greenland ice sheets have revealed previously unappreciated feedback processes that can accelerate climate change on decadal to centennial timescales. Indeed, the analogues of such abrupt changes have been identified in the climate records of the last deglaciation. In recent years, an increasing number of investigations have suggested that global and regional climate variability during the current interglacial period (beginning ca 11,600 cal year B.P., Before Present) may have played a pivotal role in the flourishing and deterioration of human civilizations across the globe. Historically, some of the most influential human civilizations have dwelled in the area between the northern coasts of the Persian Gulf and the eastern Mediterranean Sea (Fertile Crescent) since the early Holocene. Surprisingly, however, few high-resolution records of Holocene climate variability are available from this climatically complex region.

We present an exceptionally high-resolution record of multiple organic biomarkers and geochemical proxies from an ombrotrophic (rain-fed) peat complex around a tectonic lake in NW Iran that spans the last 13000 years. Down-core X-ray fluorescence abundances of


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conservative lithogenic elements (e.g., Al, Zr, Ti) as well as redox-sensitive and mobile elements (e.g., Fe, K, Rb, Zn, Cu, and Co) at 2-mm intervals reveal several episodes of elevated dust input to this region since the early Holocene.

Organic biomarker profiles co-vary closely with conservative lithogenic elements (Al, Si, Ti), indicating a potential link between climate change and the dominant plant ecology. Major episodes of enhanced dust deposition are in good agreement with other proxy records that document more arid climate in eastern Mediterranean Sea during these intervals. The relationship between periods of elevated dust input and the response of civilizations in the region, such as the Akkadian and Persian Empires, can also be inferred from variation of conservative lithogenic elements, particularly since 4200 cal yr B.P. Several significant periodicities (e.g. 750, 900, 1550 and 3000 yr) observed from wavelet analysis of refractory elements correspond with the timing of internal climate feedbacks and/or solar variability as potential modulating mechanisms for abrupt climate change in West Asia during the Holocene.



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Geomorphological evidence of the level and climate changes of Zer ibar Lake in the Holocene

Maghsoudi Mehran1, Azizi Ghasem2, Jafar Beglou Mansour3, Rahimi Omid4*

1- Associate Professor of Physical Geography (Geomorphology), Faculty of Geography,University of Tehran, Enghelab Avenue, Tehran, IRAN. 2- Associate Professor of Physical Geography (Climatology), Faculty of Geography,University of Tehran,Enghelab Avenue, Tehran, IRAN. 3- Assistant Professor of Physical Geography (Geomorphology), Faculty of Geography,University of Tehran,Enghelab Avenue, Tehran, IRAN. 4*- Msc in Physical Geography (Geomorphology), Sanandaj, IRAN.

Lakes are very interesting sedimentary environments for the

study of ancient climate, changes in sedimentary environments and lake level changes. Lake zeribar is situated in the province of Kurdistan, in the Zagros Mountains and three kilometers north-west of Marivan.

The main purpose of this research is study, geomorphological evidence from the study of mineralogical composition and grain size sediments accumulated in Zeribar lake sediments in order to check the water level fluctuations, climatic and environmental changes in during the Holocene.

688 cm of the cores obtained from wells using Russian peat corer from the Zeribar lake. Sedimentological and geochemistry analyzes included sediments grain size by using a laser diffraction particle size analyzer, clay mineralogy and XRD were performed.The age determination of three samples are based radiocarbon dates( AMS ) performed by Institute of Accelerator Analysis Ltd, Shirakawa Analysis Center, Japan. The descriptive statistics (mean, standard deviation, kurtosis and skewness) profile and type of clay minerals (illite, kaolinite) showed various degrees of fluctuations. Both short-and long- terms. Changes in climate and lake size appear to be the main factors affecting the variability in the grain-size distribution, properties and type of clay minerals. The results of the data analysis suggests the existence of warm and wetter climate, increased spring rains, episode of higher lake water level, existence of fresh-water


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conditions, prevailing high-energy condition, dominance of erosional processes, seasonal supply of detritus, inflows strength and dominance of chemical weathering about 8944-7878, 6850-6700, 6100-5500 and 2500-2100 cal yr BP. The existence of dry climate, reduced rainfall, occurrence drought,lake-level lowering, , prevailing low-energy condition, absent of seasonal supply of detritus, down conditions tidal changes and dominance of physical weathering about 7878-6100 and 5500-3150 cal yr BP.

And suggested that during the late Holocene 3150-1300 cal yr BP variations of water-level occurred irregularly, as effects of precipitation changes, occasional lake overflows and perhaps also human activities.




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Palynological reconstruction of the Caspian Sea level oscillations dur ing the past 3000 years

Elias Ramezani*1,2, Almut Spangenberg2, Ata Abdollahi Kakroodi3, Hans Joosten2

1: Department of Forestry, Faculty of Natural Resources, Urmia University, Urmia, Iran. 2: Department of Peatland Studies and Palaeoecology, Institute of Botany and Landscape Ecology, Ernst-Moritz-Arndt-University, Grimmer Straße 88, D-17487 Greifswald, Germany. 3: Faculty of Geography, University of Tehran, Tehran, Iran.

A 5.35 m sediment core of peat over clay and wood pieces was

collected using a Russian-type corer (50 cm length, 5 cm diameter) from the center of MZG mire (Nowshahr; (Mazandaran Province, N Iran; 22 m bsl; N 36˚36′17′′; E 51˚36′21′′) in May 2005. Pollen samples were taken at 20 cm intervals and prepared following standard techniques (cf. Fægri and Iversen, 1989). Five 14C-AMS-datings were carried out in order to determine the age of major palynological events throughout the record. The MZG pollen record has registered vegetation history of the central Caspian regions over the past three millennia. The lowermost ca. 60 cm of the core consists of fluvial deposits which may suggest the fall of Caspian Sea level. This is followed by the rise of Alnus, Carpinus, Fagus, and fall of Artemisia and Chenopodiaceae and Amaranthaceae (C-A) at around 2700 BP, which could be indicative of cooler and wetter climate. A major highstand at 2600 BP has been recognized for the Caspian Sea which is synchronous with periods of global cooling and wetter climates. Our record suggests that the 2600-BP highstand of the Sea continued to around 2200 cal BP, as is evidenced by findings of Carophyets and the subsequent lagoonal deposits and findings of numerous Caspian Sea fauna (e.g. Cerastorderma sp., Dressena sp., Pyrgula sp., Cyprideis sp., and Hypanis sp.) and also Gloeotrichia, and diatoms. This reconstructed sea level rise can explain the overall low values of Alnus and the sharp decrease of Pterocarya for this time span, suggesting that there was little


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sufficiently dry site for trees to grow in the lowlands. Alder and wingnut thus should have retreated to a few remaining hummocks in the lowland or even retreated to the southern foothills. Unfavorable condition should also have precluded the development of forbs (Artemisia and chenopods) in the lowland. For the period 1,600-1,100 BP, it appears from the high values of Alnus and Pterocarya that their corresponding pollen producers, i.e. alder and wingnut were dominant local elements, which might imply hydrologic changes in the lowland areas. The most conspicuous feature of the upper part of MZG diagram is the substantial decrease of Pterocarya pollen at around 1,100 BP, which is well synchronous with a climatic phenomenon known as Mediaeval Climatic Anomaly, hence suggesting a regional climate change for northern Ian.



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Natural and ar tificial bar r iers: Sasanian defensive walls on the Caspian Sea Results of a joint project by the ICHHTO and the Universities of Edinburgh and Durham

Jebrael Nokandeh, Hamid Omrani Rekavandi, Eberhard Sauer

The rapidly changing sea-level of the Caspian Sea posed major challenges to Sasanian architects one and a half millennia ago. A series of major Sasanian walls radiate from the world’s largest inland sea, most notably the Great Wall of Gorgan and the Tammisheh, Ghilghilchay and Derbent Walls. The walls ran invariably from high up in the mountains to the contemporary shore, some four metres deeper in the Sasanian era than today, to make it difficult for enemies to bypass them. The Derbent Wall was even built into deep water, its terminal being c. two metres below the Sasanian sea-level and six metres below the current – a most remarkable achievement of engineering - making it impossible for enemies to walk around its terminal in shallow water. It also would have made the wall invulnerable even in case of minor water level fluctuations. The Great Wall of Gorgan and the Tammisheh Wall may well have been joined, running along the shore, thus creating an impenetrable barrier almost 250 km long. More research is needed though to decide whether the two walls were indeed joined or whether both had their own seaside terminals. The Gorgan Wall project, examining a section of the Tammishe Wall submerged now and of the Gorgan Wall, submerged around 1400, has shed fascinating new light on the challenges posed by the rapidly changing water levels of the Caspian Sea.



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The story of a vanishing lake: Geochemical and sedimentological evidence for anthropogenic and climate impact on Urmia salt lake in NW Iran

Orash Sharifi1,2*, Ali Pourmand1, Omid Haeri-Ardakani3,2

1: Division of Marine Geology and Geophysics, University of Miami, Rosenstiel School of Marine and Atmospheric Science, Miami, FL, USA. 2: Iranian National Institute for Oceanography, Marine Geology Division, P.O. Box 14155-4781 Tehran, Iran. 3: University of Windsor, Department of Earth and Environmental Sciences, Ontario, Canada

Urmia, the third largest saline lake on earth and the largest

continental lake in the Middle East, is a hypersaline shallow lake (average salinity ~200 ‰) located in a closed continental drainage basin in northwestern Iran, and is surrounded by a variety of rock formations, ranging in age from Precambrian metamorphic complexes to Holocene mud deposits. Due to a combination of dry climate and anthropogenic impact, average Lake level has dropped by > 9 m over the last two decades, with no signs of improvement in recent years. Lake sediments are composed of two major components; chemical-biochemical and clastic fractions. Based on grain size analysis of samples from 24 push-cores, silt-size particles (3.9-62.5µm) dominate the lake’s sediments with clay-bearing materials mostly present near the center of the lake. Sand-size particles (62.5-2000µm) are dominant in the northwest, where felsic to intermediate plutonic and metamorphic rocks are located in the proximity of the lake. Based on chemical analysis of conservative lithogenic elements (e.g., Ti, Si, Al, Ca) as well as redox-sensitive elements (e.g., Fe, K, Rb, Sr) in the clastic fraction of the lake's sediment, elemental distributions are reflective of regional geology.

The water of the Urmia Lake can be classified as Na-K-Cl-Mg-SO4 brine. Ion concentrations in water varies seasonally, in northern part of the lake concentrations of ions are nearly constant throughout the year while south-southeastern parts of the lake show variable annual ion concentration due to major fresh water inflows. The main


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sources of ions to the lake are evaporite formations with minor contribution from igneous rocks. Chemical analysis of the surface sediment samples for heavy metals

(Ni, Cr, V and Hg) indicate moderate to high degrees of contamination in the affected areas, where Hg is the most abundant heavy metal. The highest concentrations of Hg (Normalized Enrichment Factor =6) are observed in the middle part of the lake, where intensive dredging and construction activities have taken place. In contrast, the lowest concentrations of Hg in undisturbed areas of the lake reveal that the heavy metals have been introduced to the lake environment in recent years. Excessive damming (28 operational, 15 under construction and 19 others under study) on the tributaries that supply water to the lake along with poor water management have drastically decreased the water supply into the lake over the last three decades. In addition, construction of Kalantari Highway across the lake (started in 1980) has significantly disturbed the natural water and sediment circulation, resulting in enhanced differential evaporation between the northern and southern “sub-basins” of the lake. In the summer of 2012, we recovered a series of split cores from the eastern part of the lake with the goal to reconstruct climate and hydrological variabilities over the Holocene and the Anthropocene at high resolution. Preliminary results from these cores indicate several episodes of fluctuation in lake's water level in the past.



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Climate and Environmental History in the Lake Victoria basin dur ing the Late-Glacial to Late-Holocene: Evidence from Pollen and Non-pollen Palynomorphs

Casim Umba Tolo*, Julius Bunny Lejju Department of Biology, Mbarara University of Science and Technology. P.O. Box 1410, Mbarara, Uganda

The period between 12400 to 10000 yr. BP is reported as

marking climatic transition in eastern Africa characterized by warming and moist climate, punctuated with arid conditions. Nevertheless, timing of the climatic transition and its oscillation with vegetation dynamics during Late-Glacial for Lake Victoria basin is far from sufficiently demonstrated and remains unclear. Similarly, evidence of vegetation dynamics in eastern and central African region in the form of ecological and ecosystem responses to climate variability and change in the past have been increasingly influenced by human activity especially during Late-Holocene period, and thus become increasingly difficult to isolate from anthropogenic signals in the sedimentary records. It becomes even more difficult if a single proxy is used in such a reconstruction. We examined evidence from pollen and non-pollen palynomorphs (e.g. charcoal, spores, Pediastrum species and δ13C isotope) from multi-sediment cores (code named here as K4L, LVNG2 and KAG2) obtained from within Lake Victoria to unravel Late-Glacial to Late-Holocene climate and environmental history in the lake’s basin. We investigated extent of vegetation changes and main drivers for the changes, climatic variations and link with palaeo-lake level dynamics. AMS14C dating provided chronological age for the sediment cores. Results provide time-constrained historical perspective on Late-Glacial to Late-Holocene vegetation dynamics and climatic variability in Lake Victoria basin; and permit to trace, a semi-quantitative depth and/ or surface-area inference of palaeo-lake levels of the lake. Period between ca. 12033 ± 60 to 10691 ± 60 yr. BP was dominated by C4-types of vegetation cover. Onset of forest recovery followed,


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continued uninterrupted between ca. 11843 ± 60 and 11673 ± 60 yr. BP, with increasing diversity in arboreal taxa, and subsequent development of forests under wet-humid climate in the basin prior to ca. 11311 ± 60 yr. BP and thereafter. Period ca. 11311 ± 60 to 10715 ± 60 yr. BP was marked by repeated decline and recovery of forest alternating with increase and decline in non-arboreal pollen taxa inferring low humidity at ca. 11230 ± 60 yr. BP and ca. 10737 ± 60 yr. BP. Forested vegetation is inferred between ca. 10715 ± 60 to 10691 ± 60 yr. BP under wet conditions. On the other hand, pollen and charcoal records infer a mixture of both dry and humid climatic conditions between ca. 4186 ± 40 and 1830 ± 40 yr. BP. A closed vegetation cover was re-established in the lake’s basin towards ca. 1320 ± 40 yr. BP and ca. 1247 to 190 ± 40 yr. BP, becoming more humid with dense forest cover at ca. 458 ± 40 yr. BP. However, from ca. 190 ± 40 to 70 ± 40 yr. BP, δ13C values, indicate drastic vegetation changes, from a C3-type to a C4-type, presumably as a result of human-induced forest disturbance.




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Sasanian Sub-aquatic: The Underwater Survey of the Tammīsheh and Gorgān Walls. Results of a joint project by the ICHHTO and the Universities of Edinburgh and Durham

Julian Jansen van Rensburg

An underwater survey of the Gulf of Gorgān and the south-eastern section of the Caspian Sea took place between 2007 and 2009. The aims of this sub-aquatic survey were to look for remains of the Tammīsheh and Gorgān Walls, previously discovered by a team of Iranian underwater archaeologists in 2001; to ground truth satellite imagery of submerged structures in the Gulf of Gorgān and determine the extent of the submerged remains of the Gorgān Wall. In this paper the three seasons of underwater surveys undertaken and the results achieved are discussed in relation to the rapidly changing sea-level of the Caspian Sea. The focus of this paper will be on the structures that were mapped and areas searched beneath the Gulf of Gorgān and south-eastern section of the Caspian Sea, looking at what we know about the inundation of the Tammīsheh and Gorgān Walls, and how and what the human response was to this event. This will take into account all aspects of the underwater and foreshore survey together with ethnographical work undertaken during the course of the Gorgān Wall project.



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A Programmatic Research Plan to Mitigate the Impacts of Global Change in Central Iran

Wigand, Peter E. Department of Geography, University of Nevada, Reno, Reno, NV 89557-0154 Department of Geology, California State University, Bakersfield, Bakersfield, CA 93311-1022

We present a phased program for the identification and

mitigation of the potential impacts of future climate change based upon past paleoecological proxy data. The identification of wetter climate episodes has been selected because surficial processes in arid and semi-arid regions are accelerated during such periods whether they are warmer or cooler. Phase1) Identify Past Climatic Episodes: Paleoenvironmental data from throughout the eastern Mediterranean, and northeastern Africa indicate at least three long-term episodes of wetter climate whose onset was dramatic characterize the Holocene. Each episode was marked by dramatic different causes, and by radically different characteristics as well. Proxy data from stratigraphic and sedimentological, palynological, macrobotanical, diatom, and ostracod studies evidence these climatic episodes, and reveal the nature of these events. The earliest event around 9,600 rcyr B.P. reflects the northward movement of the Intertropical Convergence Zone characterized by warm, wet climate comprised of summer rains. An episode of winter dominated rainfall between about 3,700 and 2,600 rcyr B.P. is stronger in the north than in the south. Finally an episode between ~2,100 and 1,400 rcyr B.P. is characterized by dramatic, nearly decadal variation in late Spring to early Summer shifted precipitation. The onset of each of these episodes is usually dramatic and each phase is characterized by extreme variability. Phase 2) Assess Paleoclimatic Impact Upon Surficial Processes: We already know from studies in other regions of the world what the expected response of geomorphic or surficial processes may be under specific regimes of past climate. Because of their extremely different natures, each of these climate regimes had dramatically different effects on surficial processes, especially in


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desert environments. In particular, aeolian and alluvial processes (the most important in desert environments) reveal dramatic differences in both their predominance as sediment transport agents, but also in the magnitudes of their effectiveness. Phase 3) Generate Predictive Models of Future Regional and Local Climate: Global change scenarios from local to regional levels are available and could be applied to the region of interest. In some cases modification of the scenario might be required based upon the information gleaned from studies conducted in Phase 1. Phase 4) Identification of the Response of Surficial Processes: After selection of the best scenario for future climate, we can then identify the response of surficial processes on both a local and regional scale. Under some scenarios alluvial processes will be accelerated and become more prominent as a geomorphic process. Under other scenarios aeolian processes might predominate. In other cases they might both be come more active. We might also expect, based upon other studies that there might be a lag in the response of geomorphic processes. Phase 5) Formulate a Plan of Mitigation: In many cases changes in geomorphic/surficial processes will have detrimental effects upon people. However, if we have predictions of potential changes in these processes, we should be able to formulate and recommend, based upon in other parts of the world, ways of reducing the harmful impacts of these changes upon people.



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Use of Multiple Proxy Data to Track Rapid Changes in the Depth of Tulare Lake in the San Joaquin Valley, Southern California

Wigand, Peter E.1, Rob Negrini1, Manuel Palacios-Fest2

1: Department of Geology, California State University, Bakersfield, Bakersfield, CA 93311-1022 2: Terra Nostra Earth Sciences Research, LLC, 6312 N Barcelona Lane # 606, Tucson, AZ, 85704-5425

ABSTRACT. Past levels of Tulare Lake, San Joaquin Valley,

southern California, are being used to forecast future Sierra Nevada Mountain run off and water supply to a thirsty population. Tulare Lake, once the largest (1,600 km2 and 12 m deep) lake in the U.S. west of the Great Lakes, is fed by four rivers which rise in the Sierra Nevada Mountains, the Kings, Kern, Tule and Kaweah, Consequently, the lake directly reflects precipitation in the Sierras. Since the 1800s agricultural diversion of steams feeding the lake has led to it’s rapid decline and eventual desiccation. Previous studies by two of our authors (Negrini et al. 2006) revealed a general 12,000-year lake level history recorded in the stratigraphy of trenches excavated into the former lake’s western shoreline. A dramatic increase in lake depth followed by a precipitous drop in lake depth between 3,200 and 2,800 cal B.P. provides the bases for the current study. Mapping and dating of shallow water deposits near this shoreline provides an accurate overview of lake depth and by extrapulation lake extent. This information is combined with data collected from cores taken in continuously deposited sediments just off shore of these trenches. Samples taken from these cores have been used to obtain: 1) increased magnetic susceptibility, and 2) increased grain size as indicators increased input of inorganic sediment during increased stream input, 3) increased total organic carbon as a measure of increased marsh, 4) increased total inorganic carbon as reflection of drought, 5) increased carbon/nitrogen ratios during deep lake, 6) ostracods as a reflection lake chemistry, 7) increased diatom abundance, another measure of lake chemistry, especially during the


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influx of fresh water, 8) mesotrophic versus eutrophic algae presence as a measure of deep lake versus marsh, and 9) pollen as a measure of the dynamics of marsh versus desert shrub vegetation surrounding the lake as climate changed, and the amount of exposed shore changed. Each of these data can be used individually, but used together they provide a robust and continous record of changes in past lake levels and the impact of climate change on a large interior lake system during the late Holocene. Not only is the history of lake level fluctuations more continous now, but more importantly we now have a clearer idea of the impact of climate change upon sediment transport in regional streams, lake chemistry, and the dynamics of adjacent vegetation.



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Appandix Field Brochure

the foreword - brunel university london · dynamics during the late-glacial to early holocene. ......

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