鄂尔多斯盆地绥靖地区长7油层组沉积相特征研究

在前人研究成果的基础上,通过对鄂尔多斯盆地绥靖地区15口取心井岩心、测井、沉积构造以及野外露头等资料进行综合研究,并采用沉积学原理和方法对绥靖地区三叠系延长组长7油层组的沉积环境进行了系统分析。结果表明,长7油层组为三角洲沉积体系,主要发育三角洲平原亚相,并进一步划分出了三种沉积微相:分流河道、天然堤和分流间洼地微相;分流河道和天然堤微相为储集层骨架砂体。同时对长7油层组各小层(长71、长72、长73)沉积微相的空间展布特征进行了分析,认为油气聚集受有利沉积相带的控制,三角洲平原上的分流河道微相和天然堤微相是油气聚集的主要场所,也是下一步油气勘探开发的方向。

Study on sedimentary facies characteristics of Chang-7 oil reservoir group in Suijin area,Ordos basin

On the basis of predecessors' research results,through comprehensive analysis of 15 coring Wells cores,well logging,sedimentary structure and field outcrop data,by adopting the principle and methods of sedimentology,the systematic analysis on sedimentary environment on Triassic Chang-7 oil reservoirs in Suijin area has been carried out.The results show that Chang-7 oil reservoirs belong to delta sedimentary system,and the delta plain subfacies have been mainly developed.Three sedimentary microfacies have been further classified:distributary channel,natural levee and split between depressions microfacies.Distributary channel and the natural levee microfacies have sand bodies of reservoir skeleton.At the same time,the research on spatial distribution characteristics of small layers of Chang-7 oil reservoir,namely Chang 71,Chang 72 and Chang 73 has been carried out.The results believe that the hydrocarbon accumulation is controlled by favorable sedimentary facies belt,the distributary channel microfacies and natural levee microfacies on the delta plain are the main oil and gas gathering places,and it is the further direction for oil and gas exploration and development in the next step.