基岩油气成藏特征与中国陆上深层基岩油气勘探方向  

Hydrocarbon accumulation characteristics in basement reservoirs and exploration targets of deep basement reservoirs in onshore China

作　　者：汪泽成[1] 江青春[1] 王居峰[1] 龙国徽[2] 程宏岗[1] 施亦做 孙琦森 姜华[1] 阿布力米提·依明[3] 曹正林[1] 徐洋 陆加敏[4] 黄林军[1] WANG Zecheng;JIANG Qingchun;WANG Jufeng;LONG Guohui;CHENG Honggang;SHI Yizuo;SUN Qisen;JIANG Hua;ABULIMITI Yiming;CAO Zhenglin;XU Yang;LU Jiamin;HUANG Linjun(PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;PetroChina Qinghai Oilfield Company,Dunhuang 736202,China;PetroChina Xinjiang Oilfield Company,Karamay 834000,China;PetroChina Daqing Oilfield Co.,Ltd.,Daqing 163458,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油青海油田公司,甘肃敦煌736202 [3]中国石油新疆油田公司,新疆克拉玛依834000 [4]中国石油大庆油田有限责任公司,黑龙江大庆163458

出　　处：《石油勘探与开发》2024年第1期28-38,共11页Petroleum Exploration and Development

基　　金：中国石油天然气集团有限公司科技项目“陆相深层超深层油气富集规律与勘探评价技术研究”(2021DJ02)。

摘　　要：基于全球基岩油气藏数据库和中国基岩油气藏解剖,深入分析基岩油气成藏特征,探讨深层基岩油气成藏的有利条件和勘探方向。研究表明:全球已发现的基岩油气田主要分布在埋深小于4500 m的中浅层,层位以太古宇和前寒武系为主,储集层岩性以花岗岩和变质岩为主;规模较大的基岩油气田主要分布在中新生代构造运动活跃的裂谷盆地、弧后盆地和前陆盆地。基岩油气成藏特征主要表现为:(1)以孔隙-裂缝型低孔特低渗储集层为主,非均质性强,强抗压实作用导致储集层物性不受埋深控制,规模成储期为盆地基底风化剥蚀期及后期构造改造期;(2)他源供烃,成藏组合可划分为烃源岩-基岩接触型和烃源岩-基岩分离型两大类;(3)烃源岩异常高压和基岩储集层常压-低压,导致烃源岩与储集层之间存在较大的压力差,有利于深层基岩抽吸成藏。基底构造活动性、成藏组合关系、深大断裂(尤其走滑断裂)发育程度及区域性盖层等是深层基岩选区评价的主要参数;古老克拉通盆地陆内裂谷边缘的前寒武系结晶基底、紧邻生烃凹陷的古生代褶皱基底和中新生代块断基底,均具有较好的成藏条件,是未来深层基岩油气勘探的主要方向。Based on the global basement reservoir database and the dissection of basement reservoirs in China,the characteristics of hydrocarbon accumulation in basement reservoirs are analyzed,and the favorable conditions for hydrocarbon accumulation in deep basement reservoirs are investigated to highlight the exploration targets.The discovered basement reservoirs worldwide are mainly buried in the Archean and Precambrian granitic and metamorphic formations with depths less than 4500 m,and the relatively large reservoirs have been found in rift,back-arc and foreland basins in tectonic active zones of the Meso-Cenozoic plates.The hydrocarbon accumulation in basement reservoirs exhibits the characteristics in three aspects.First,the porous-fractured reservoirs with low porosity and ultra-low permeability are dominant,where extensive hydrocarbon accumulation occurred during the weathering denudation and later tectonic reworking of the basin basement.High resistance to compaction allows the physical properties of these highly heterogeneous reservoirs to be independent of the buried depth.Second,the hydrocarbons were sourced from the formations outside the basement.The source-reservoir assemblages are divided into contacted source rock-basement and separated source rock-basement patterns.Third,the abnormal high pressure in the source rock and the normal–low pressure in the basement reservoirs cause a large pressure difference between the source rock and the reservoirs,which is conducive to the pumping effect of hydrocarbons in the deep basement.The deep basement prospects are mainly evaluated by the factors such as tectonic activity of basement,source-reservoir combination,development of large deep faults(especially strike-slip faults),and regional seals.The Precambrian crystalline basements at the margin of the intracontinental rifts in cratonic basins,as well as the Paleozoic folded basements and the Meso-Cenozoic fault-block basements adjacent to the hydrocarbon generation depressions,have favorable conditions for hydroca

关 键 词：基岩油气藏 花岗岩储集层 成藏组合 抽吸成藏 走滑断裂带 深层基岩 

分 类 号：TE122.3[石油与天然气工程—油气勘探]