Palaeoenvironment of the Barents Sea since the Last Glacial Maximum

Abstract

The palaeoenvironment of the Barents Sea and adjacent area since the Last Glacial Maximum (LGM) was reconstructed on fourteen gravity cores retrieved during a Korea-Russia joint cruise in 2002-2004. The Barents Sea sediments were classified into nine sedimentary facies: massive dark gray diamicton during the LGM

stratified dark gray diamicton, (light) olive gray clay, and light brownish (sandy) mud during the last deglaciation

and greenish gray mud, laminated greenish gray clay and mud, (cross-stratified) olive gray muddy sand, greenish gray sandy mud, and brownish mud during the Holocene. The grain size distribution, total organic carbon and total nitrogen contents, and the carbonate content for all the cores were analyzed at 2-4cm intervals. The depositional age was determined by AMS radiocarbon isotope dating on shell fragments. Sedimentological and geochemical analyses reveal that during the LGM, the Barents Ice Sheet had not developed over the Saint Anna Trough eastward. Early Holocene sedimentation in the Barents Sea is characterized by a high sedimentation rate accompanied by a rapid relative sea level rise. Cyclic sedimentation in a periodical anoxic environment occurred in the Pechora Sea. The sedimentation rate in the Barents Sea has decreased since 7-8 ka with a slowdown of the relative sea level rise, and coarse-grained sediment was deposited in the Pechora and southeastern Barents seas. A decrease in the sedimentation rate since the middle Holocene resulted in the formation of an oxidation crust in trough regions.