Zhangqiang Depression Oil Deposit Forma Tion Characteristics And Exploration Targ Et Optimization

Zhang Qiang depression is a depression in Liaohe peripheral basins of many great exploration potential, the relatively high abundance of oil and gas resources in a Mesozoic depression. The sag sand clastic rocks and the Yixian Formation volcanic rock two sets of the main oil-bearing series, exist in Zhanggutai sag and seven shijiazi sag in the north and south two students subsag, two sag stratum structure, sedimentary environment, volcanic rock distribution characteristics are different, complex geological conditions; reservoir types in the region are more abundant, but oil and gas into reservoir controlling factors and accumulation of relatively weak, the favorable exploration direction has not been very clear, need to further study.The study by Zhang Qiang depression in Liaohe area as the scope of the study, in view of the problems existing in the area, use of drilling, seismic, testing and analysis of data, to oil and gas into the reservoir conditions of foundation, analysis of clastic rock and volcanic rock oil and gas controlling factors of hydrocarbon accumulation, summed up the oil and gas accumulation rules, preferably favorable exploration target zone.First,The stratigraphic features of Zhangqiang depression: sag southern(seven shijiazi sag) age of the basement of the old, the northern(Zhanggutai sag) age of the basement of the new; II Southern Mesozoic strata thickness, burial depth, thin stratum of northern, shallow burial; north and South Regions Mesozoic in lithology, sedimentary environment were different. Next, tectonic framework, fault distribution and trap are characterized by: overall fracture to NE, NW and near ns to give priority; and the secondary fracture control depression boundary and secondary structure distribution zone, three faults control the local configuration and trap. Discovery and favorable traps 17, the cumulative area of about 70 km2 implementation.Analysis shows that the reservoir conditions. Near the oil source, oil and gas migration, the main point of effective reservoirs and traps are the main controlling factors of reservoir into clastic rock reservoirs. Near sag, near the faults, the local structure or high volcano organization center facies is the most favorable area of volcano rock reservoir. Fan delta, delta front sub phase sand body and effusive facies in upper sub phase pore almond, fractured andesite is the most favorable reservoir facies belt. Intergranular pore and fracture is the main reservoir space. Lithologic reservoir is the main reservoir type structure. Development of Jiufotang formation, Shahai formation 2 sets of dark mudstone, belong to good source rocks, type II and type III kerogen, low mature mature; Qi Jia Zi source sag conditions better than Zhang Zhang gutai sag.Through comprehensive analysis that: along the eastern sag NS trending fault zones and sag area, close to the most favorable clastic rocks in the oil and gas exploration target zone is; close to Zhanggutai sag on the west side of the volcanic rocks in the structural high is currently the preferred area of volcanic rocks in the oil and gas exploration.