南襄盆地泌阳凹陷南部陡坡带隐蔽油气藏形成与分布

FORMATION AND DISTRIBUTION OF SUBTLE RESERVOIRS IN THE SOUTHERN STEEP SLOPE ZONE IN THE BIYANG SAG OF THE NANXIANG BASIN

南襄盆地泌阳凹陷南部陡坡带不同地区发育了不同类型的隐蔽油气藏。双河地区形成砂岩上倾尖灭及断层—岩性复合油气藏;赵凹—安棚地区主要形成成岩物性封堵、上倾尖灭及透镜状浊积砂体油气藏;下二门地区主要形成断层—岩性复合油气藏;边界大断裂附近发现少量地层不整合油气藏和基岩潜山油气藏。控制该区隐蔽油气藏形成与分布的主控因素有古构造背景、油气疏导体系、生储盖组合等,其中,断层作为油气的疏导体系是影响油气分布的主要因素。

The southern steep slope zone in the Biyang Sag of the Nanxiang Basin, is characterized by various categories of subtle hydrocarbon reservoirs. In Shuanghe area, the updip pinch-out sandstone reservoir and the fault-lithologic reservoir dominate over others. In Zhaowa-Anpeng region, the updip pinch-out reservoir and the lenticular turbidite reservoir are the major categories. In Xiaermen area, the fault-lithologic reservoir precedes. Near the large boundary faults, a small quantity of the unconformity reservoir and the buried hill bedrock reservoir have also been drilled. The formation and distribution of subtle reservoirs in this region are controlled by various factors, such as the palaeotectonic setting, the migration pathway of hydrocarbon and the source-reservoir-caprock assemblage, of which the fault as a migration pathway of hydrocarbon is the major factor to control the hydrocarbon occurrence. It is significant for the oil and gas exploration to recognize the hydrocarbon-forming model and its primary controlling factor in different area.