柴西阿尔金山前下中侏罗统沉积地球化学特征及意义

Sedimentary geochemistry and significance of the Middle and Lower Jurassic strata in the frontal areas of the Altun Mountains,Qinghai

依据柴达木盆地西部阿尔金山前红沟子北部地区黑石山地质调查,结合样品的地球化学分析资料,对该区下中侏罗统的沉积特征和沉积环境进行了详细研究。其结果表明柴西阿尔金山前黑石山山顶下中侏罗统层位在横向上不见其相同层位,且岩性特征与山底区别较大,判断山顶上的下中侏罗统可能为"飞来峰";柴西阿尔金山前下中侏罗统的沉积环境为还原环境,有利于有机质的保存和烃源岩的生成,具有一定的油气勘探前景。

The sedimentary environments of the Middle and Lower Jurassic strata are discussed on the basis of geology and geochemical signatures of the samples from the Heishi Mountains in the frontal areas of the Altun Mountains, Qinghai. It is inferred, from the horizontal stratal differences and vertical lithologic differences between the top horizons and basal horizons of the Middle and Lower Jurassic strata in the study area, that the Middle and Lower Jurassic strata on the top may be assigned to the ＂ klippes＂. These Middle and Lower Jurassic strata laid down in the reducing environments are favourable for the preservation of organic matter and generation of the source rocks, indicating the potential of oil and gas exploration.