塔中地区东部中古51井区鹰山组碳酸盐岩油、气、水分布复杂。为探求鹰山组油气分布及成藏特征,通过对现有油、气、水勘探成果、断裂特征及储盖组合进行分析,应用常规测井、成像测井、地震及地化等多种方法开展研究。研究表明,该井区鹰山组储层以孔洞型和裂缝-孔洞型为主,沿不整合面准层状分布。走滑断裂有着明显的控藏作用,油气井多分布在距离主干走滑断裂0.5~4.0 km范围内,产量随着离断裂距离的减少有增加的趋势;油气各地化性质距离走滑断裂也呈规律性的变化,呈现出“近断裂气远断裂油”的平面分布局面。良里塔格组良三-良五段联合鹰山组内部数套高阻层组成多套封隔盖层,垂向上多套储盖组合相互叠置,油气多层聚集。早期油藏受后期气侵影响,使得垂向上具有“上油下气”的特点。油气在盖层及走滑断裂的联合控制下,在有利的构造圈闭和岩性圈闭内成藏。
Oil/gas/water distribution is complex in the marine carbonate reservoirs of the Yingshan Formation in ZG-51 well-block of eastern Tazhong area .Based on analysis of the existing oil and gas exploration results ,fault characteristics and reser-voir-seal assemblage ,we studied the oil/gas distribution and accumulation characteristics of the Yingshan Formation by using various data such as routine logging ,image logging ,seismic data and geochemical data .The reservoirs of Yingshan Formation in this wellblock are predominantly of vuggy type and fractured-vuggy type,and show quasi-layer distribution along unconformi-ties.The strike-slip faults significantly controlled hydrocarbon accumulation .The distance between oil/gas wells and major strike-slip faults ranges from 0.5 to 4.0 km.The daily oil and gas output decreases away from the strike-slip faults.The geo-chemical behaviors of oil and gas also changes regularly with the distance to the strike-slip faults.In plane view,the gas reser-voirs are near the faults,while oil reservoirs are far from these faults .The 3rd to 5th members of Lianglitag Formation as well as the high resistive intervals of the Yingshan Formation act as barriers .Vertically,multiple reservoir-seal combinations superim-pose each other,resulting in oil/gas accumulation in multiple layers .The early oil pools were influenced by gas invasion in later stage ,resulting in the vertical distribution characteristics of “upper oil and lower gas”.Hydrocarbons accumulated in favorable structural traps and lithologic traps under the jointly control of cap rocks and strike -slip faults.