琼东南盆地深水区结构构造特征及油气勘探潜力

在对新采集和处理的高精度地震资料进行详细的构造-地层解释的基础上，将琼东南盆地划分为北部隆起区、中央坳陷区和南部隆起区3个一级构造单元，并识别了重要的北西向“堑垒”构造带，表明盆地整体呈现“南北分带，东西分块”的基本构造格架特征。对北部隆起区和中央坳陷区重要分界地质标志——2号断裂系统开展了详细的地质构造解释和断裂活动性定量分析，证实2号断层具有区段式活动特征。研究了各构造单元凹陷的结构特征，识别出半地堑、地堑和复式地堑3种基本类型和与之对应的10种次级类型。以盆地构造单元划分为基础，结合已有地质资料和勘探成果，综合分析认为盆地各区带具有良好的油气勘探潜力。图8参22

Structural characteristics and petroleum exploration potential in the deep-water area of the Qiongdongnan Basin, South China Sea

According to analysis of the newly acquired high-quality seismic reflection data, the Qiongdongnan Basin is divided into three first-order structural units, i.e. northern uplift, central depression, and southern uplift. An NW-trending graben and horst belt is identified, showing that the structural framework of the basin is characterized by zones in the north-south direction and blocks in the west-east direction.. A detailed interpretation of geological structures and quantitative analysis of faulting is carried out on No. 2 fault system, which is an important boundary marker between the northern uplift and the central depression. Results indicate that No. 2 Fault is characteristic of segmented faulting. The structural characteristics of sags in each structural unit is studied and the sags are classified into three types, half-graben, graben, and compound graben, which are further divided into ten subtypes. On the basis of the structural unit classification, along with existing geological data and exploration achievements, it is believed that the petroleum exploration potential is good in the structural units of the basin.