额济纳旗及其邻区二叠系哈尔苏海组烃源岩综合评价

Comprehensive Evaluation on Permian Ha'ersuhai Formation Hydrocarbon Source Rocks in Ejina Banner and Its Vicinity

通过对额济纳旗及其邻区二叠系哈尔苏海组烃源岩分布、有机质丰度、有机质类型和有机质成熟度的综合研究,总结了烃源岩的分布特征和地球化学特征。哈尔苏海组暗色泥岩平面上主要分布在雅干-哈尔苏海地区,且在上段和下段均有分布,厚度为143.7～969.6m。考虑风化作用的影响,分别对478、霍东哈尔和哈尔苏海3个剖面的烃源岩分层进行有机质丰度评价,区内哈尔苏海组发育中等-好的烃源岩,烃源岩有机质类型以Ⅱ1型为主。受断裂活动的影响,灰石山东北-霍东哈尔地区有机质成熟度较高,处于过成熟阶段,其他构造活动较弱地区烃源岩处于成熟-高成熟阶段。额济纳旗及其邻区二叠系哈尔苏海组烃源岩生烃潜力较大,该区具有良好的油气勘探前景。

Based on the comprehensive research of distribution,organic matter abundance,its type and maturity of Permian hydrocarbon source rocks of Ha'ersuhai Formation in Ejina Banner and its vicinity,the distribution and geochemical characteristics were summarized.The dark mudstones of Ha'ersuhai Formation were mainly distributed in the plane of Yagan-Ha'ersuhai Area,they were distributed both on upper and lower sections with the thickness of 143.7~69.6m.In consideration of the effect of weathering,the organic matter abundance of layered hydrocarbon source rocks were evaluated respectively in three sections of 478,Huodonghaer and Ha'ersuhai Formations,the middle-good hydrocarbon source rocks were developed in Ha'ersuhai Formation.The kerogen type was divided by using steranes relative content,and the type of hydrocarbon source rocks was mostly Ⅱ1 in Ha'ersuhai Formations.Influenced by fault movement,organic matter maturity of northeast Huishishan-Huodongha'er is overmatured,which is unfavorable for oil and gas generation.The hydrocarbon source rocks of the other area with weak structural activity are at maturity-high maturity stage.The hydrocarbon generating potentials of hydrocarbon source rocks are relatively large in Ha'ersuhai Formation,and better exploration prospects are obtained in Ejina Banner and its vicinity.