非震综合物探方法在辽西牛营子地区油气地质调查中的应用

为系统研究辽西牛营子地区的地层及断裂展布、深部构造特征等关键基础地质问题, 开展油气远景区评价, 在建立该区物性结构模型的基础上, 综合处理解译重磁电等地球物理资料, 确定了本区断裂特征、构造格架、中生代地层展布及有利生储盖组合的综合物探异常特征。结果显示: 研究区内共有断裂26条, 走向主要有NNE—NE向、NW向, 前者以逆冲为主, 后者以平移为主, 兼具逆冲, NNE向断裂控制了本区的构造格架; 区内划分出5个二级构造单元, 呈"三凹二凸、凹凸相间"的格局, 其中, 牛营子凹陷夹持于逆冲断裂间, 中生界底面最大深度达2400 m, 侏罗系发育全, 厚度大; 宋杖子凹陷呈断坡, 中生界底面最大深度达1200 m; 三家子凹陷为东倾单斜, 中生界底面最大深度达1400 m。依据石油地质条件及解释成果, 牛营子凹陷北票组-海房沟组烃源岩发育, 确定为油气勘探有利区。研究成果为辽西牛营子地区油气勘探及工作部署提供了重要的地球物理学依据。

Application of non seismic comprehensive geophysical prospecting method in oil and gas geological survey in Niuyingzi area,western Liaoning Province

In order to systematically study the strata, fault distribution, deep structural characteristics and other key basic geological problems in Niuyingzi area, western Liaoning Province, and carry out the evaluation of oil and gas prospect areas, this paper, based on the establishment of physical property structure model and comprehensive processing and interpretation of gravity-magnetic-electric and other geophysical data, determines the comprehensive structure of fault characteristics, structural framework, Mesozoic strata distribution and geophysical abnormal characteristics of the under combination's favorable combination of reservoir. The results show that: there are 26 faults in the study area, and the strike is mainly NNE-NE and NW. The former is dominated by thrust, while the latter is dominated by translation with both thrust. The NNE faults control the structural framework of the area; the study area is divided into five secondary structural units, showing a pattern of three concave and two convex, alternating concave and convex. Among them, Niuyingzi sag is sandwiched between thrust faults, the maximum depth of the bottom of Mesozoic is 2400 m, and the Jurassic system is fully developed with large thickness; Songzhangzi sag is a fault slope, and the maximum depth of the Mesozoic bottom is 1200 m, Sanjiazi sag is an East dipping monocline, and the maximum depth of the Mesozoic bottom is 1400 m. According to the petroleum geological conditions and interpretation results, the source rocks of Beipiao formation-Haifanggou formation in Niuyingzi sag are well developed, which is determined as a favorable area for oil and gas exploration. The research results of this paper provide an important geophysical basis for oil and gas exploration and work deployment in Niuyingzi area, western Liaoning Province.