Objective To study the effect of different sedimentary environment on shale organic matter enrichment with the shales from the Carboniferous Gaolishan Formation in Chaohu area of Anhui province.Methods Based on organic geochemical and elemental geochemical analyses,the differences of organic matter enrichment and sedi-mentary environment characteristics of the Gaolishan shales were investigated.Results The research results showed that the Gaolishan shales had a low TOC content ranging from 0.03％to 0.89％with low generation po-tential,and Tmax values from 519 to 543℃ indicated that shales had evolved into the highly mature stage.As to the elemental geochemistry,the Gaolishan shales had a Fe2O3 content ranging from 2.19％to 17.90％,indicating that the changes of the sedimentary water depth and the alternation of oxidation/hypoxia was relatively frequent.The paleo-productivity,hydrodynamics,paleo-salinity and redox elements parameters reflected the evolution trend of the sedimentary environment during the Gaolishan Period,which changed from the quiet and oxidized fresh water environment in the lower part to the turbulent and reduced brackish water environment in the upper part.Conclusion The Gaolishan Formation is developed in the environment of low paleoproductivity,turbulent and oxidation water body,not conducive to the enrichment of organic matter.The relatively high TOC contents of Member Ⅰ shales indicate that paleoproductivity and quiet water environment are the main influencing factors of organic matter enrichment in study area.
NETL
NSTL
维普
万方数据
