摘要
Abstract
In order to reveal the evolution process of Mahai sag in Qaidam basin, taking data of major elements, trace elements and rare elements of Paleogene Neogene mudstone in study area, using the numerical value com⁃parison and the chart identification, the provenance attitude, tectonic setting and palaeoclimate have been studied in this paper. The REE distributions of mudstones show LREE enrichment, have a flat HREE pattern and a week Eu anomaly. As showed by the numerical of V/(V+Ni),Ce/La and Ceanom, the palaeoclimate in anaerobic environ⁃ment. From the discrimination diagram of La/Yb ∑REE, La/Sc Co/Th, K2 O/Na2 O SiO2/Al2 O3 , La Th Sc、Th Sc Zr/10, Paleogene Neogene mudstone in Mahai sag in the area are in active continent magin and continental island arc environment. Felsic volcanic rock and femic rock could be seen, provenance parent rock com⁃position is quite complicated. Chemical Index alteration ( CAI) and the ratio of Sr/Cu indicate that the intensity of chemical weathering is relatively hot and week, and tectonic setting belongs to an active tectonic zone.关键词
古-新近系/地球化学特征/物源分析/马海凹陷/柴达木盆地/青海省Key words
Paleogene Neogene/geochemical characteristics/provenance analysis/Mahai sag/Qaidam basin/Qinghai province分类
天文与地球科学
