noble gases; terrestrial fluid emanation; lake sediments; paleoseismology; recent earthquake; biomarkers and paleo-productivity; cosmogenic nuclides and solar activity; paleoclimate in the Middle East
Tomonaga Yama, Brennwald Matthias S., Livingstone David M., Kwiecien Olga, Randlett Marie-Ève, Stockhecke Mona, Unwin Katie, Anselmetti Flavio S., Beer Jürg, Haug Gerald H., Schubert Carsten J., Sturm Mike, Kipfer Rolf (2017), Porewater salinity reveals past lake-level changes in Lake Van, the Earth’s largest soda lake, in Scientific Reports
, 7(1), 313-313.
Tomonaga Y., Brennwald M. S., Livingstone D. M., Tomonaga G., Kipfer R. (2014), Determination of natural in vivo noble-gas concentrations in human blood, in PLoS ONE
, 9, e96972.
Stockhecke M., Anselmetti F.S., Meydan A-F., Odermatt D., Sturm M. (2014), The annual particle cycle in Lake Van (Turkey), in Palaeoecology
, 333-334, 148-159.
Cukur D., Krastel S., Tomonaga Y., Çağatay M. N., Meydan A. F. (2013), Seismic evidence of shallow gas from Lake Van, eastern Turkey, in Marine and Petroleum Geology
, 48, 341-353.
Glombitza C., Stockhecke M., Schubert C.J., Vetter A., Kallmeyer J. (2013), Sulfate reduction controlled by organic matter availability in deep sediment cores from the saline, alkaline Lake Van (Eastern Anatolia, Turkey), in Frontiers in Extreme Microbiology
, 4, 209.
Stockhecke M. (2013), The annual particle cycle in Lake Van (Turkey). Palaeogeography, Palaeoclimatology, in Palaeoecology
, 1, 1-10.
Tomonaga Y., Brennwald M. S., Kipfer R. (2013), Using helium and other noble gases in ocean sediments to characterize active methane seepage off the coast of New Zealand, in Marine Geology
, 344, 34-40.
Randlett M.E. , Coolen M.J.L., Stockhecke M., Pickarski N., Litt T., Balkema C., Kwiecien O., Tomonaga Y., Wehrli B., Schubert C.J., Alkenone distribution in Lake Van sediments over the last 600 kyrs: influences on temperature and haptophyte species composition, in Quaternary Science Review
Stockhecke M., Kwiecien O., Vigliotti L., Anselmetti F.S., Beer J., Namik Çağatay M., Channell J.E.T., Kipfer R., Litt T., Pickarski N., Sturm M., Chronostratigraphy of the 600,000 year old continental record of Lake Van (Turkey), in Quaternary Science Reviews
Kwiecien O. ., Stockhecke M., Haug G.H., Kipfer R., Litt T., Pickarski N., Sturm M., Anselmetti F.S., Dynamics of the last four glacial terminations recorded in Lake Van, Turkey, in Quaternary Science Reviews
Tomonaga Y., Brennwald M. S., Meydan A. F., Kipfer R., Noble gases in the sediments of Lake Van - Solute transport and palaeotemperature reconstruction, in Quaternary Science Review
Stockhecke M., Sturm M., Brunner I., Schmincke H.-U., Sumita M., Kipfer R., Kwiecien O., Cukur D., Anselmetti F. S., Sedimentary evolution and environmental history of Lake Van (Turkey) over the past 600,000 years, in Sedimentology
Cukur D., Krastel S., Schmincke H.-U., Sumita M., Çağatay N., Meydan A.F., Damcı E., Stockhecke M., Seismic stratigraphy of Lake Van, eastern Turkey, in Quat. Sci. Rev.
Cukur D., Krastel S., Schmincke H.-U., Sumita M., Tomonaga Y., Çağatay M.N., Water level changes in Lake Van, Turkey, during the past ca. 600 ka: climatic, volcanic and tectonic controls, in J. Paleolimnol.
This SNF proposal seeks funding for the continuation of the Swiss contribution to the Lake Van Drilling Project executed by the International Continental Scientific Drilling Program (ICDP). Among other previous Swiss ICDP engagements, the Lake Van Drilling project was pivotal in triggering the newly established SNF-supported Swiss membership in ICDP. Further, the SNF Swiss contribution is a central building block of the entire ICDP PaleoVan initiative.Lake Van is the fourth-largest terminal lake in the world, extending 130 km WSW-ENE 1674 m above sea level on a high plateau in eastern Anatolia, Turkey. The lake is surrounded by active volcanoes within a tectonically active area and it is known to accumulate fluids emanating from the Earth’s mantle.The partly annually-laminated sedimentary record down to 220 m depth recovered from Lake Van during the ICDP PaleoVan drilling operations in 2010 has been shown to be an excellent palaeoclimate and palaeoenvironment archive. The continuous, high-resolution continental sequence, which covers several glacial-interglacial cycles (> 500 kyr), represents a unique possibility to investigate in detail the climatic, environmental, and volcanic changes that occurred in the Near East, the cradle of human civilization, during much of the Quaternary Period. Furthermore, the sediments contain an invaluable record of past earthquake activities, allowing the construction of a catalogue of prehistoric earthquakes and making it possible to study fluid transport in the continental crust that was triggered by seismic events. In this context, the societal vulnerability of the area to seismic hazards was dramatically documented by the occurrence of the devastating earthquake of magnitude 7.2 close to the city of Van on 23 October 2011 (hereafter referred to as the VE11 earthquake). This unfortunate and tragic event offers a unique opportunity to calibrate the past seismic events recorded in the sediments of Lake Van and the related emission of fluids from the solid earth to a modern seismic analogue. Sediment and fluid transport triggered by this major seismic event need to be quantified in order to calibrate the sedimentological record, which is targeted by the follow-up field campaign proposed within this project extension.The continuation of the Swiss initiative, embedded in the overarching ICDP drilling project on Lake Van, encompasses all the 5 initial research modules (A-E) of the ongoing SNF project (200021_124981). Within this proposal extension, the extended modules (A*-E*) will focus on key issues and new developments that expand the initial topics, with a special emphasis on the recent major earthquake VE11 and its biogeochemical and sedimentological implications. At the same time, this extension will also allow the results that have already been acquired to be further analysed and written up for publication by the project team. A large number of publications is foreseen.Module A*: Calibrating the prehistoric seismic event catalogue: The signature of the recent magnitude 7.2 earthquake in the Lake Van sedimentary record: The devastating VE11 earthquake with epicentre located 16 km north-east of the city of Van allows investigation of the impact of an instrumentally quantified seismic event on the sediments of Lake Van. For this purpose, during an additional field campaign we propose to collect a series of short cores at various locations within Lake Van a varying epicentral distances. This study will allow the response of the finely laminated sediments to seismic shaking of known intensity to be calibrated and the area of the lake affected by the VE11 event to be investigated. A short core at the ICDP Ahlat Ridge drilling site will be taken to investigate possible sediment deformations that may be compared directly with the numerous deformed layers in the ICDP drill cores. The seismic-hazard assessment accomplished through the palaeoseismic investigation of the drilled cores will thus be quantified and significantly improved.Module B*: Signature of tectonic activity and active fluid emission imprinted in the Lake Van water column. As a result of extensive research conducted during the last two decades, the hydrochemistry of Lake Van is relatively well known. Anomalies in the concentration of major ions will facilitate assessment of the influence of the VE11 earthquake on the geochemical composition of the water column. Additionally, in combination with extended CTD profiles, we plan to measure the concentration of radon (radionuclide 222Rn) on-line and at different water depths to determine the physical state of the water column. Due to its short half-life (~3.8 days) and its biogeochemical inertness as a noble gas, radon is an ideal conservative tracer to study active and very recent fluid emission from the lake sediments into the water column.Module C*: Alkenones as markers for palaeotemperature and palaeosalinity, and for use in an independent age model. Module C focuses on organic matter and more specifically on organic molecules used as proxies for reconstructing palaeoenvironments (so-called biomarkers). The potential of biomarkers in the sediments of Lake Van was evaluated in 2011 by identifying and quantifying alkenones (C37-38, lacustrine markers) and n-alkanes (C29, terrestrial marker) within 60 samples distributed over the entire profile. The continuation of the project will focus on the D/H ratios of those markers to reconstruct palaeosalinity and humidity/aridity patterns. Whereas investigation of the D/H ratios of land-derived markers (long chain n-alkanes) will reveal precipitation patterns in the Lake Van region, investigation of the D/H ratio in alkenones will allow the salinity of Lake Van water to be reconstructed over time. We will collect surface-water and rainwater samples and will determine their D/H ratios to reveal fractionation patterns between water sources and biomarkers.Module D*: Beryllium-10 as a tracer of solar and geomagnetic variability and erosion rate. Work on polar ice cores has proven 10Be to be an excellent tracer for the reconstruction of the long-term history of solar and geomagnetic variability. The sediments of Lake Van have a unique potential not only to extend the 10Be ice core records from about 100,000 yr to 500,000 yr, but also to increase their temporal resolution to a few years by analysing the varved sections of the ICDP PaleoVan drill cores. However, during wet periods with increased erosion rates the solar and the geomagnetic signal may have been disturbed. During such periods 10Be can serve as a tracer for particle transport. Our main focus will be on the reconstruction of the decadal to centennial variability of solar activity for times not accessible via polar ice cores (100-500 kyr).Module E*: Using noble gases to determine the impact of the VE11 event and related tectonic activity on the release of sediment porewater and mantle-derived fluids in Lake Van. In combination with CTD profiles, noble-gas, CH4, and CO2 concentrations and d13C values measured in the water column of Lake Van will be used to study the impact of the VE11 earthquake on the physical flux and accumulation of mantle-derived fluids in Lake Van. In particular, the accumulation of He will allow the fluid emission from the sediments into the water body of Lake Van to be identified and characterized geochemically. The results will be interpreted within the context of the ongoing noble-gas measurements in the ICDP PaleoVan sediment porewater samples in terms of terrigenic fluid transport mechanisms and past seismic events.As in the ongoing SNF project, these five independent research modules will complement each other and will comprise critical components of the multinational and multidisciplinary effort to reconstruct the Quaternary history of Lake Van.