zum Inhalt springen

German contribution to the Elgygytgyn Drilling Project

The German contribution to the international El´gygytgyn Drilling Project was mainly funded by the German Ministry for Education and Research (BMBF). The BMBF funds provided about a third of the drilling costs, complemented by almost identical funding by the US Nationals Science Foundation (NSF) and the International Continental Scientific Drilling Program (ICDP), but also substantial support of the pre-site survey and the geoscientific investigation of the drill cores obtained.

First funding was provided in 10/2002 - 12/2005 for a "Pilot Study on Lake El´gygytgn" (grant no. 03G0586 A, B). German partners in this collaborative project, which was coordinated by Martin Melles, at that time at the University Leipzig, were the Alfred Wegener Institute (AWI) in Bremerhaven and in Potsdam. Its major objective was to test the hypothesis that Lake El´gygytgyn in remote Chukotka, Russian Arctic, which was formed by a meteorite impact crater some 3.6 Ma ago, hosts a unique sedimentary archive that reflects the environmental and climatic history of the Arctic throughout much of the Quaternary and potentially even Pliocene. For that purpose, we carried out comprehensive investigations (i) on the modern sediment genesis in Lake El´gygytgyn in dependence on the current climatic and environmental conditions, and the Late Quaternary sedimentation history - University Leipzig, (ii) on the constitution and history of the permafrost in the catchment of the Lake - AWI Potsdam, and (iii) on the thickness and layering of the entire sediment infill and the underlaying impact breccia. The results are based on extensive field and lab work, which involved monitoring programs, surface sediment sampling and shallow coring in the lake and in the permafrost catchment, as well as shallow and deep seismic surveys on the lake. They basically confirmed the project hypothesis and opened new opportunities for additional funding.

With regard to BMBF funding, the project was followed up by the collaborative BMBF project "Deep Drilling in Lake El´gygygtyn", which was funded 11/2006 - 10/2011 (grant no. 03G0642 A, B, C). This project was coordinated by Martin Melles at the University of Cologne. It consisted of four individual projects that concerned (i) the project coordination and the Pliocene and Quaternary paleolimnology from the Lake El´gygytgyn drill cores - University of Cologne, (ii) the sediment-physical properties of the El´gygytyn drill cores - AWI Bremerhaven, (iii) the permafrost history from the drill cores recovered in the periglacial surroundings of Lake El´gygytgyn - AWI Potsdam and (iv) the geochronology of the El´gygytgyn drill cores - GeoForschungsZentrum (GFZ) Potsdam. The investigations strongly build on drill cores, which were recovered in the El´gygytgyn Crater in 2008/09. Drilling comprised the entire, ca. 320 m thick lake sediment record and the upper ca. 200 m of the underlying impact breccia, and the upper ca. 140 m of permafrost deposits in the western lake catchment. The investigation of the drill cores confirmed a continuous sediment accumulation in Lake El´gygytgyn since the time of the meteorite impact. Gravitational mass movements are frequent, but led to only minor disturbance of the pelagic sediments, which could be properly dated by paleomagnetic dating and correlation of sediment proxies to known climate changes. A perennial lake ice cover first occurred at the Pliocene/Pleistocene boundary 2.6 Ma ago, however, full frequency of glacials with perennial lake ice was not obtained before ca. 1.8 Ma. The interglacials during the Quaternary exhibit distinct variability in intensities. The so-called "super interglacials" detected obviously correspond with melting events in Antarctica.

Complementary funding for the investigation of the drill cores from the lake sediments was provided by the German Research Foundation (DFG), including the projects Lake Elgygytgyn - Pliocene Arctic vegetation and Lakes Baikal and Elgygytgyn - paleoclimate comparison, which were run 2011 - 2017 and 2012 - 2017 by Martin Melles and Alexander Prokopenko at the University of Cologne.