PaleoVan - The Lake Van Drilling Project

Principal Investigator

Prof. Dr. Thomas Litt, Rheinische Friedrichs-Wilhems-Universität Bonn, Nussallee 8, D-53115, Bonn, Germany.

Homepage of the PALEOVAN project

An international research group is proposing a new research initiative, the Lake Van Drilling Project ‘PaleoVan’ within the framework of ICDP.
The planned project will address several key questions related to the suitability of long continental lacustrine sediments as high-resolution paleoclimate archives.

Specific goals of the proposed PaleoVan project

(1) Paleoclimate in a sensitive semiarid region based on transfer functions (pollen, stable isotopes) and modeling;
(2) Climate variability in space and time based on teleconnection with other high-resolution records such as ice cores and marine sequences;
(3) Dynamics of lake level fluctuations and hydrogeological development;
(4) Formation and age of Lake Van;
(5) History of volcanism and volcanic activities based on tephrostratigraphy;
(6) Variations of the earth-magnetic field;
(7) Tectonic, paleoseismic and earthquake activities;
(8) The interaction between man and environment since prehistoric times

Paleoclimate

The controversial nature of the discussion of present and future global warming has shown that it is crucial to increase our knowledge of past climate change to better understand the dynamics and amplitude of the global climate system in space and time. In continental regions this information can be obtained from lacustrine sediments, where biotic and abiotic parameters provide proxy climate data. In this respect, Lake Van, the fourth-largest terminal lake in the world, situated in Turkey, promises to be an excellent paleoclimate archive. It has the potential to yield long continental records covering several glacial-interglacial cycles from annually-laminated sediments.

Human agriculture

An interesting aspect of the project is the discovery of specific Pollen in the uppermost part of sediments. These pollen might shed light on the history of the human agriculture in this cultural rich region, part of the Fertile Crescent.

Pollen from olive trees (Olea europeaea) indicate long distance transport from the Mediterranean region in the Lake Van record. Quercus sp. pollen is very common during the climate optimum of the Holocene. Pollen grains from steppic plants such as Artemisia and chenopods are common during cooler and/or dryer phases. Not shown are pollen grains from Cereals, which are native in the Near East (wild cereals). Higher percentages in Holocene pollen assemblages, however, indicate human impact.

Pollen from Olea, Quercus, Artemisia and a chenopod, viewed by confocal microscopy.

Group of volcanoes near Lake Van in eastern Anatolia

> Nemrut Dagi
> Mount Suphan, a magnificent dormant volcano northwest of Lake Van

Geology

Lake Van is on a high plateau in eastern Anatolia. It has a surface area of 3,522 km2, a volume of 576 km3, a maximum depth of 451 m, and it extends for 130 km WSW-ENE. The present lake level is at 1,648 m above sea level. The climate of the area is continental, with hot and dry summers, and cold winters. The Lake Van drainage basin covers 16,096 km2 and lies within the eastern part of the larger Muş Basin. Lake Van water is highly alkaline, with a PH reaching 9.8.  Salinity is 22 ppm, and calcium concentration is low. The southern shore is formed by the Bitlis massif (3,500 m above sea level). The area north and west of the lake is dominated by the large volcanos Nemrut and Süphan. Lavas and/or pyroclastic flows sourced in Nemrut volcano may have built the dam that now separates Lake Van from the rest of the Muş Basin. Rivers within the Lake Van basin discharge water and sediment into the lake, which has no outflow today.
Lake Van is the fourth-largest terminal lake in the world.

History of the Lake Van Project

Sediment cores recovered already in 1974 during a German expedition (University of Hamburg) provided evidence of an annually-laminated varve sequence. High-resolution hydrochemical, geochemical, geological, and biological investigations of Lake Van were continued in 1990 during a German-Swiss expedition (EAWAG Zürich, University Hamburg). Initial reconstruction of the frequency, duration, and rate of climate change in eastern Anatolia during the last 12,500 years was based on varve counting. Continuous records of varve thickness, geochemistry, stable isotopes, and pollen indicated several different climate phases and at least 11 volcanic ash layers.

In the light of these results, ICDP Germany, the priority program of the German Research Foundation (DFG) promoted a pre-site survey as a basis for future scientific studies and drilling initiatives on continent.

To exploit the potential of the site, an ICDP workshop was held in Van, Turkey, on June 6-9, 2006 (link mit den Workshops bei uns auf der Seite), organized by the Institute of Paleontology, University of Bonn (Germany), and hosted by the University of Van (Turkey). Thirty-five researchers from 12 countries took part in the meeting.

 VIDEO - a short video feature in German language on the Paleo Van Project can be found within the > Resources-Section.