Geochemistry and environment evolution of Core E in the Laizhou Bay since last stage of Middle Pleistocene
Geochemistry and environment evolution of Core E in the Laizhou Bay since last stage of Middle Pleistocene作者机构:Ocean University of Qingdao Qingdao 266003 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China
出 版 物:《Acta Oceanologica Sinica》 (海洋学报(英文版))
年 卷 期:2001年第20卷第3期
页 面:391-399页
核心收录:
学科分类:0710[理学-生物学] 070902[理学-地球化学] 0709[理学-地质学] 0908[农学-水产] 07[理学] 0707[理学-海洋科学]
主 题:Laizhou Bay last stage of Middle Pleistocene geochemistry paleo-environment element strata
摘 要:Geochemistry analysis has been done on Core E (37 07 N, 118 55 E; depth: 82.1 m) taken from the Laizhou Bay in 1994. Nine kinds of invariable elements, 15 kinds of microelements and the content of lime carbonate are measured by means of ICP. The results indicate that most of the invariable elements and microelements in Core E show significant changes in the boundary stratotype, and the ratios between elements (Mn/Fe, Sr/Ba, Ti/Al) in particular. So they can be used as characteristic indicator to stratigraphic division of Quaternary. The changes of invariable elements are primarily controlled by the host minerals, and they mainly indicate the provenance as well as the sedimentation and depositional environment. Several elements, such as Fe, Al, Ca, Mg, Mn and Ti, are very sensitive to the provenance and environment. The distribution of microelements differs in four depositional periods: last stage of Middle Pleistocene, last interglacial period, last glacial period and Recent epoch, and especially in the cold period and warm period . The loops in the cycle curves of the most microelements correspond with the sand bed sediments, among which there are six sand units representing warm period sediments, and one representing cold period sediments. The carbonate is on the high side in the aeolian silt sediments formed in the glacial lowering of sea level in Core E, but on the low side in the transgressive sand beds formed in the interglacial period. The content variation of carbonate has a direct bearing on the grain size and the styles of sediments, and is a good indicator to the climate, environment and stratigraphic division.