鄂尔多斯盆地深层寒武系碳酸盐岩储层特征与主控因素

寒武系是鄂尔多斯盆地重要的油气勘探潜力层系。基于最新钻井、野外露头、地震资料和镜下薄片鉴定，识别出其主要发育相控型和构造强改造型两大类储层，进而细分出8类储集体，其中表生岩溶储集体和高能云化鲕粒滩是鄂尔多斯盆地寒武系的主要储集体。寒武系碳酸盐岩储集体的储集空间类型丰富，孔、洞、缝均发育，不同储集体类型的储集空间类型差异明显。提出了寒武系储层发育主要受控于高能相带云岩、古隆起区表生岩溶作用和断裂活动等3方面因素，建立了寒武系储层模式图。在此基础上探讨了鄂尔多斯盆地寒武系碳酸盐岩油气勘探方向，指出盆地西南缘的庆阳古陆周缘地区的寒武系岩溶缝洞型储集体发育区是重点勘探地区。

Characteristics of deep Cambrian carbonate reservoirs in the Ordos Basin and main control factors

The Cambrian carbonates are important oil and gas exploration targets in the Ordos Basin.An integration of the latest drilling and seismic data as well as outcrop and thin section observation shows that the Cambrian carbonates contain two major categories of reservoirs, i.e.facies-controlled and intensively structure-modified reservoirs.They can be further subdivided into eight types, of which the epigenetic karst and high-energy dolomitized oolitic shoal are the main reservoirs.The Cambrian carbonates are characterized by well-developed pores, cavities and fractures of different types and high diversity.The study proposes that the Cambrian reservoir development is mainly controlled by the dolomite of high-energy facies, epigenetic karstification of the paleo-uplift zone and faulting activity.And a model for the Cambrian reservoir development is also established.In addition, a discussion based on the study was carried out for the exploration direction of the Cambrian carbonates in the Ordos Basin and it is concluded that the Cambrian fractured-vuggy karst reservoirs around the Qingyang paleo-land at the southwestern margin of the basin shall be the next focus for exploration.