Petromagnetic parameters of bottom sediments as indicators of the climatic and environmental changes in the central zone of the Sea of Okhotsk during the last 350 kyr
M.I. Malakhov a , S.A. Gorbarenko b , G.Yu. Malakhova a , N. Harada c , Yu.P. Vasilenko b , A.A. Bosin b , E.L. Gol'dberg d , A.N. Derkachev b
a Northeastern Interdisciplinary Research Institute, Far Eastern Branch of the RAS, 16 ul. Portovaya, Magadan, 685000, Russia
b Pacific Oceanological Institute, Far Eastern Branch of the RAS, 43 ul. Baltiiskaya, Vladivostok, 690041, Russia
c Institute of Observational Research for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka, 690 Sekine, Mutsu 035-0022, Japan
d Institute of Archeology and Ethnography, Siberian Branch of the RAS, 17 prosp. Akad. Lavrent'eva, Novosibirsk, 630090, Russia
Keywords: bottom sediments; petromagnetism; relative paleointensity; magnetoclimatic parameters; paleoclimatic changes; Late Pleistocene; Sea of Okhotsk
Pages: 973-982
Abstract
Bottom sediments from the central zone of the Sea of Okhotsk were preliminarily dated. The petromagnetic parameters of two groups of samples formed at cold and warm climatic stages were studied. Warm oxygen isotopic stages and substages were characterized by the coexistence of pseudo-single-domain allogenic magnetite and predominant magnetite and greigite (pyrrhotite) grains subject to biologic control. At cold stages, sediments containing a mixture of pseudo-single-domain and multidomain terrigenous magnetite particles accumulated. The petromagnetic curves agree with the normalized standard oxygen isotopic curve over the last 350 kyr of the column section.
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