제4기 퇴적작용에 해한 규소 및 탄산염의 선택적 모드: 동해 퇴적물에 대한 고찰

Abstract

Previous data from East Sea (Sea of Japan ) sediment cores show that the biogenic fractions such as organic matter, carbonate and biogenic opal exhibit large fluctuation. Especially, during glacial and interglacial period the content of carbonate and biogenic opal show cyclic variation, but carbonate and biogenic silica contents vary inversely. Data from the Ulleung Basin (cores 97PC-19 and 94PC-2) and Korea Plateau (96EBP4) show that carbonate content increases during glacial intervals and decreases during interglacials, whereas biogenic silica increases during interglacial intervals and decreases during glacial intervals. It is proposed that this distinctive pattern results from alternating states of the ocean system. The obvious inverse correlation between carbonate and biogenic silica content supports the idea of two mutually exclusive modes of biogenic pelagic sediment accumulation. Cores from East Sea locations where the sea floor is deeper than the carbonate compensation depth contain no such alternate modes, suggesting that carbonate dissolution or dilution by terrigenous material has taken place.