石油实验地质2025，Vol.47Issue(3)：530-540,11.DOI:10.11781/sysydz2025030530
东海盆地西湖凹陷平湖斜坡油气差异富集特征及主控因素
Differential characteristics and main controlling factors of hydrocarbon enrichment in Pinghu Slope,Xihu Sag,East China Sea Basin
摘要
Abstract
The Pinghu Slope in the Xihu Sag of East China Sea Basin exhibits significant hydrocarbon exploration potential,characterized by strong heterogeneity in its enrichment patterns.Investigating the differential enrich-ment characteristics and their main controlling factors can offer a theoretical basis for oil and gas exploration in the Xihu Sag and similar areas.To this end,the study thoroughly examined typical hydrocarbon reservoirs and analyzed logging,seismic,and physical property testing data.It investigated the differences in enrichment and layer distribution of hydrocarbons in the Pinghu Slope and identified their influencing factors.The findings indi-cated a gradual decrease in hydrocarbon enrichment from the southern zone to the northern zone of the Pinghu Slope.Structural and lithologic as well as faulted anticline hydrocarbon reservoirs exhibited higher enrichment than faulted noses and fault block reservoirs.The hydrocarbon-enriched layers were classified into three types:multilayer enrichment in the Pinghu and Huagang formations,enrichment in the middle and upper sections of the Pinghu Formation,and enrichment in the lower and middle sections of the Pinghu Formation.The differential hydrocarbon enrichment in the study area was controlled by hydrocarbon supply distance,reservoir conditions,trap conditions,and fault sealing ability.Specifically,the hydrocarbon supply distance mainly controlled the differences in enrichment between different structural zones and reservoir types,while the differences in hydro-carbon enrichment between reservoirs of the same types were also influenced by reservoir conditions,trap condi-tions,and fault sealing ability.Shorter hydrocarbon supply distances,greater effective reservoir thicknesses,larger trap areas,and stronger fault sealing ability led to higher hydrocarbon enrichment.The vertical distribution of the hydrocarbon enrichment was influenced by fault transport capacity as well as fault and caprock configuration.When the fault's vertical transport capacity was robust and the residual sealing thickness exceeded the lower limit,hydrocarbons tended to accumulate in the middle and upper sections of the Pinghu Formation of the lower part of the regional caprock.In cases where the fault had a strong vertical transport capacity and had completely broken the caprock in the Pinghu Formation,hydrocarbons accumulated in both the Pinghu and Huagang formations.Conversely,when the fault transport capacity was weak,hydrocarbons mainly accumulated in the lower and middle sections of the Pinghu Formation.By focusing on the hydrocarbon supply distance,reservoir conditions,fault transport capacity,and fault and caprock configuration,this study provides a basis for determining the differences in hydrocarbon enrichment and identifying oil and gas enrichment strata in the Xihu Sag and similar areas.关键词
油气差异富集/供烃距离/储层条件/圈闭条件/断层输导与封闭/断—盖配置/西湖凹陷/东海盆地Key words
differential hydrocarbon enrichment/hydrocarbon supply distance/reservoir conditions/trap condi-tions/fault transport and sealing/fault and caprock configuration/Xihu Sag/East China Sea Basin分类
石油、天然气工程引用本文复制引用
郭刚,苏圣民,徐建永,廖计华,李林致,李峰..东海盆地西湖凹陷平湖斜坡油气差异富集特征及主控因素[J].石油实验地质,2025,47(3):530-540,11.基金项目
中海油重大科技项目"中国近海新区新领域勘探技术"(KJGG2021-0300)资助. （KJGG2021-0300）
