河北省开平向斜页岩气地球化学特征及生烃潜力评价

Geochemical Characteristics and Hydrocarbon Generation Potential Evaluation of Shale Gas in Kaiping Syncline of Hebei Province

石炭-二叠系是河北省开平向斜主要的含煤地层,煤系地层中的暗色泥页岩具备赋存页岩气的条件。通过对研究区内的样品进行岩石学分析、地球化学分析、含气性分析认为:研究区内泥页岩有机质类型以Ⅱ2型为主,以一般烃源岩为主,有机质成熟度属于高成熟-过成熟阶段;泥岩的矿物组成以黏土矿物含量最高,其次是以脆性矿物中的石英为主;泥页岩孔隙度大部分为超低孔,渗透率类型为超低渗。

The Carboniferous Permian is the main coal-bearing strata in the Kaiping Syncline of Hebei Province,and the dark shale in the coal-bearing strata has the conditions for the occurrence of shale gas.Through petrological analysis,geochemical analysis,and gas-bearing analysis of the samples in the study area,it is believed that the organic matter type of the shale in the study area is mainly II,type,with general hydrocarbon source rocks as the main type.The maturity of the organic matter belongs to the high maturity to over maturity stage.The mineral composition of mudstone is mainly composed of clay minerals,followed by quartz in brttle minerals.The majority of shale porosity is ultra-low porosity,and the permeability type is ultra-low permeability.