Sediment and fluid transport triggered by major seismic events need to be quantified in order to calibrate the sedimentological record of lakes located in tectonically active areas. The continuation of the Swiss initiative within the frame of the ICDP drilling project on Lake Van will focus on the major earthquake occurred close to the lake on October 2011 and its geochemical and sedimentological implications.

Lay summary

Lake Van is the fourth largest terminal lake in the world, extending 130 km WSW-ENE at 1650 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 200m-long sedimentary record recovered from Lake Van during the ICDP PaleoVan drilling operations in 2010 has been shown to be an excellent palaeoclimate, palaeoenvironment, and palaeoseismic archive. The continuous, high-resolution continental sequence, which covers several glacial/interglacial cycles (for more than 500’000 years), represents a unique possibility to investigate in detail the climatic, environmental, and volcanic evolution 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 facilitating the study of the 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. 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 possible emission of terrigenic fluids to the recent seismic activity.

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, will put special emphasis on the recent major earthquake and its biogeochemical and sedimentological implications as a modern analogue to interpret the unique sedimentological record of the lake in terms of past seismic activity in eastern Anatolia.