松南断陷群石油勘探潜力与勘探方向分析

松南断陷群位于松辽盆地南缘,依据断陷盆地发育时代及后期改造特征,北以西拉木伦河断裂为界、南以赤峰—开原断裂为界,将松南断陷群由北到南划分为3个带:北部昌图—茫汉断陷带,中部彰武—东胜断陷带,南部黑山侏罗系残留盆地。彰武—东胜断陷带具有断陷结构好、满洼含油的特点,勘探目标应围绕断陷内具有连续层状反射特征的烃源岩展开,以寻找构造和隐蔽型油气藏作为主攻方向。昌图—茫汉断陷带九佛堂组烃源岩厚度大,烃源岩指标好,有利的勘探目标应紧邻生油洼陷或位于生油洼陷内,油气主要分布在洼陷内或与之相邻的圈闭中。 

Petroleum exploration potential and targets in fault depressions, southern Songliao Basin

The Songnan fault depressions locate in the south of the Songliao Basin. According to the development ages and late reforming characteristics of the fault depressions, with the Xar Moron River fault as the northern boundary and the Chifeng-Kaiyuan fault as the southern boundary, the Songnan fault depressions can be divided into three belts from north to south:the Changtu-Manghan fault depression belt (the north), the Zhangwu-Dongsheng fault depression belt (the middle) and the Heishan Jurassic residual basin (the south). The Zhangwu-Dongsheng fault depression belt has good structure and is rich in oil all over the belt; hence explorations should be focused on the source rocks with continuous layered reflection, and the structural and subtle reservoirs should be targeted. In the Changtu-Manghan fault depression belt, the source rocks of the Jiufotang Formation has the characteristics of big thickness and fine geochemical index, so explorations should be carried out close to or in the source faults, and oil and gas mainly distribute in traps in the fault or close to it.