通过对准页3井中芦草沟组页岩样品测试数据进行分析,探讨了页岩样品的地球化学特征及垂向变化规律,进一步阐述了其沉积环境指示意义及变化特征.结果表明准页3井芦草沟组页岩中Al和K偏低,Na、Ca和Fe偏高,P元素明显富集,整体属于较为干旱的环境;Sr/Ba与B参数特征说明芦草沟组整体处于半咸水-咸水沉积环境,垂向上盐度含量不断增大;Fe2+/Fe3、V/V+ Ni、V/Cr、LREE/HREE、δCe和δEu参数特征表明芦草沟组整体为酸化弱还原环境下近源沉积,而下段为贫氧环境,中上段为厌氧环境,且受北天山陆源碎屑和火山灰间歇性影响,为有机质的输入和保存提供了较为有利的条件.%Through analysis of Lucaogou Formation shale samples from the well ZY3,has discussed shale samples geochemical features and vertical variation pattern;and then further expounded its sedimentary environmental indicative significance and variation features.The result has shown that the elements Al and K on the low side in well ZY3 Lucaogou Formation shale,Na,Ca and Fe on the high side and P obviously enriched;indicated a rather arid environment as a whole.The Sr/Ba and B parametric features indicated brackish water to salt water sedimentary environment as a whole;from bottom to top the salinity continuously increasing.The Fe2+/Fe3+,V/V + Ni,V/Cr,LREE/HREE,δCe and δEu parametric features indicated Lucaogou Formation is a kind of proximal sedimentation under acidification weak reduction environment as a whole,while lower member under oxygen poor environment,middle and upper members under anaerobic environment.Because of intermittent impacts from the northern Tianshan Mts.terrigenous clasts and volcanic ash have provided rather favorable condition for organic matter entering into and preservation.
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