断裂附近源断砂空间配置油气运聚有利部位预测方法及其应用

为研究含油气盆地下生上储式断裂附近断砂空间配置圈闭中油气分布规律,在断裂附近源断砂空间配置油气运聚机理及有利部位研究的基础上,利用源岩排烃分布区和断裂输导油气有利部位,确定断裂附近源断空间配置油气运移有利部位;通过断裂侧向封闭分布部位和油气储集砂体发育部位,厘定断裂附近断砂空间配置油气圈闭部位,两者叠合建立了一套断裂附近源断砂空间配置油气运聚有利部位的预测方法,并将其应用于渤海湾盆地冀中坳陷廊固凹陷大柳泉地区旧州4条分支断裂附近沙三中下亚段源断砂空间配置油气运聚有利部位的预测中。结果表明:旧州4条分支断裂附近沙三中下亚段源断砂空间配置油气运聚有利部位主要分布在F9断裂、F8断裂中部西南及东北部局部和F7断裂西南部,有利于下伏沙四段源岩生成油气沿断裂附近源断空间配置油气运移有利部位向上覆沙三中下亚段断砂空间配置圈闭中运聚成藏,与目前旧州4条分支断裂附近沙三中下亚段已发现油气主要分布相吻合,表明该方法用于预测断裂附近源断砂空间配置油气运聚有利部位是可行的。

Proposed Method for Predicting Favorable Locations for Oil and Gas Migration and Accumulation in Source-faulted-sand Zones near Faults and Its Application

A set of methods is established for predicting the most favorable positions for oil and gas migration and accumulation in source-faulted-sand zones near faults. The study examined the distribution of oil and gas in traps of lower-generation and upper-reservoir faulted-sand zones near faults in petroliferous basins, based on the mechanism of hydrocarbon migration and accumulation, as well as the most favorable positions of source-faulted-sand zones near faults. This was applied to the middle and lower subsections of Es₃ near the 4 branches of Jiuzhou fault, Daliuquan area, Langgu Sag, Jizhong Depression, Bohai Bay Basin. The most likely locations of source-faulted zones for oil and gas migration in the region of source rock hydrocarbon expulsion, and favorable regions of faults for oil and gas transportation were determined. The positions of oil and gas traps in faulted-sand zones near faults were predicted from the position of laterally sealed faults and the area of sand bodies that could store oil and gas. The most favorable positions for oil and gas migration and accumulation in this region are predicted to be mainly in the F9 fault, in the area southwest of the middle part and the northeastern part of the F8 fault, and in the southwestern part of the F7 fault. These areas are beneficial for the migration and accumulation of oil and gas from the Es₄ source rock along favorable migration pathways to the faulted-sand zone traps in the middle and lower subsections of Es₃. This is consistent with the main distribution of oil and gas that have been discovered in the middle and lower subsections of Es₃ near the 4 branches of Jiuzhou fault, indicating that the proposed method is feasible for predicting favorable regions for oil and gas migration and accumulation in source-faulted-sand zones near faults.