The Thrill to Drill in the Chill — 3.6 Million Years of Arctic Climate Change from Lake El’gygytgyn, NE Russia
Julie Brigham-Grette University of Massachusetts – Amherst
Martin Melles University of Koln
Pavel Minyuk Northeastern Interdisciplinary Scientific Research Institute (NEISRI) – Magadan
Christian Koeberl University of Vienna
After several years of preparation, pre-site survey work, and arduous logistical planning, Lake El’gygytgyn is now the focus of a challenging interdisciplinary multi-national drilling campaign as part of the International Continental Drilling Program (ICDP). With drilling initiated in Nov. 2008, the goal is to collect the longest time-continuous record of climate change in the terrestrial Arctic and to compare this record with those from lower latitude marine and terrestrial sites to better understand hemispheric and global climate change.
Figure 1 – Cross section of Lake El’gygytgyn showing drilling locations.
Coring objectives include replicate overlapping lake sediment cores of 330 m and 420 m length at 2 sites (D1 and D2 in Fig. 1; four cores total) near the deepest part of the lake. Coring shall be continued 300 m (D1) and 100 m (D2) into the underlying impact breccia and brecciated bedrock in order to investigate the impact process and the response of the volcanic bedrock to the impact event. One additional land-based core (site D3) to ca. 200 m in lake sediments now overlain by frozen alluvial sediments on the lake-shore will allow better understanding of sediment supply to the lake and spatial depositional heterogeneity since the time of impact. This latter drill site at the west edge of the lake outside the talik (unfrozen ground in an area of permafrost) will also be used for permafrost studies and be permanently instrumented for future ground temperature monitoring as part of the Global Terrestrial Network for Permafrost (www.gtnp.org/index_e.html). Drilling of the primary D1 and D2 sites will take place from February to the middle of May 2009 using the lake ice as a drilling platform. The project is using a new GLAD-800 drilling system modified for extreme weather conditions by Drilling, Observation and Sampling of the Earths Continental Crust Inc. (DOSECC). Moreover, the science and logistics involves close cooperation with the Russian Academy of Sciences (Far East Geological Institute-Vladivostok; and Northeast Interdisciplinary Scientific Research Institute-Magadan) and Roshydromet’s Arctic and Antarctic Research Institute-St. Petersburg.
In summer 2009, the cores will be flown by chartered cargo plane to St. Petersburg. Later they will be trucked to the University of Cologne, Germany, for sub-sampling starting in September by the international team and their students; the archive core halves will be shipped to the University of Minnesota LacCore Facility in the US for post-moratorium studies.
The impetus for deep drilling at Lake El’gygytgyn is largely based on field and laboratory studies carried out over the past decade. Seismic work in the lake and morphostratigraphic work in the catchment and surrounding region confirmed that the lake record is undisturbed, without evidence of glaciation or desiccation (Niessen et al., 2007; Glushkova and Smirnov, 2007). A 12.9-m-long sediment core retrieved from the deepest part of the lake in 1998 revealed a basal age of ~ 250 kyr and demonstrated, using a variety of proxies, the sensitivity of this lacustrine environment to record high-resolution climatic change across NE Asia at millennial timescales (Brigham-Grette et al., 2007; Melles et al., 2007; Nowacyzk et al., 2007; Forman et al., 2007; plus 7 other papers in same issue listed in supplemental references; Fig. 2). A 16.7-m-long sediment core taken nearby in 2003 dated to nearly 300 kyr and confirmed the reproducibility of the record (Juschus et al., 2007).
This research also showed that nearly every proxy can be systemically linked to changes in the duration of seasonal lake ice cover, regional temperature, and changes in hydrologic input driven largely by high latitude precessional cycles and feedbacks. For example, the magnetic susceptibility and sedimentology showed that perennial ice cover during glacial summers led to anoxia in the hypolimnion, which had a profound impact on the biogeochemistry at the sediment/water interface (Nowacyzk et al. 2007; Minyuk et al., 2007). Knowledge of the basin geomorphology and sedimentation processes informs us of likely changes in landscape weathering and sedimentation rates (Asikainen et al., 2007; Glushkova and Smirnov, 2007). We have also demonstrated that while gravitational sediment transport occurs in the basin, such events do not cause erosion of the continuous stratigraphy in the center of the lake where drilling is planned. Documenting the dynamics and controls on the lake’s seasonal ice cover (Nolan et al, 2003; Nolan and Brigham-Grette, 2007) has been key to understanding lake circulation and beach geomorphology. Moreover, this work has been critical to developing safety plans for ice thickening and engineering prior to drilling from the lake’s frozen surface.
Figure 2 – DOSECC’s drilling platform on Lake El’gygytgyn, March 2009.
Our ability to inform policy makers about global/regional climate and related environmental change and its uncertainties depends on our capacity to understand the role of the Arctic region in modulating past periods of change under different climate forcing conditions. Of prime interest to the scientific community is determining why and how the Arctic climate system evolved from a warm forested ecosystem into a cold permafrost ecosystem between 2 and 3 million years ago. A continuous depositional record in this unique lake provides a means of capturing the mechanisms and dynamics of glacial/interglacial and millennial-scale change from this region over the duration of the “41 kyr world” and late Cenozoic “100 kyr world”. This record will then be compared with other long records from around the world, but especially the low latitude ocean records, to evaluate polar amplification, model systemic teleconnections and leads/lags relative to insolation forcing. This record will also provide insight as to whether rapid change events identified during the last glacial cycle are typical of earlier glacial periods. We hope to provide the science community with an understanding of the poorly documented regional sensitivity of the NE Asian Arctic to millennial-scale abrupt change (Heinrich and D/O scale) and interglacial warmth detected at global vs. regional scales, within the timeframe of the EPICA ice cores, long Asian loess and lake records, and comparable marine records. Climate modeling is also an important aspect of the program to allow these relationships to be evaluated systematically.
The Lake El’gygytgyn Drilling Project is an international effort funded by the International Continental Drilling Program (ICDP), the US National Science Foundation Earth Sciences Division and Office of Polar Programs (NSF/EAR/OPP), the German Federal Ministry for Education and Research (BMBF), Alfred Wegener Institute (AWI), and GeoForschungsZentrum-Potsdam (GFZ), and the Russian Academy of Sciences Far East Branch (RAS/FEB). The leading Russian institutions include Roshydromet’s Arctic and Antarctic Research Institute (AARI), the Northeastern Interdisciplinary Scientific Research Institute (NEISRI) and the Far East Geological Institute (FEGI). The deep drilling system for Arctic operations was developed by DOSECC, Inc.
Brigham-Grette, J., Melles, M., Minyuk, P. and Scientific Party, 2007: Overview and Significance of a 250 ka Paleoclimate Record from El’gygytgyn Crater Lake, NE Russia, Journal of Paleolimnology, 37: 1-16.
Gebhardt, A.C., Niessen, F. and Kopsch, C., 2006: Central ring structure identified in one of the world’s best-preserved impact craters, Geology, 34: 145-148.
Melles, M., Brigham-Grette, J., Glushkova, O.Yu., Minyuk, P.S., Nowaczyk, N.R. and Hubberten, H.W., 2007: Sedimentary geochemistry of a pilot core from Lake El’gygytgyn – a sensitive record of climate variability in the East Siberian Arctic during the past three climate cycles, Journal of Paleolimnology, 37: 89-104.
Nowaczyk et al., 2002: Magnetostratigraphic results from impact crater Lake El’gygytgyn, northeastern Siberia: A 300 kyr long high resolution terrestrial paleoclimatic record from the Arctic, Geophysical Journal International, 150: 109-126.