珠江口盆地荔湾3-1深水气田成藏模拟实验  

Geological features and gas accumulation simulation experiments of the Liwan 3-1 Gas Field in the Baiyun Sag,Pearl River Mouth Basin

作　　者：高岗[1] 刚文哲[1] 张功成[2] 何文军[1,3] 崔鑫[1] 沈怀磊[2] 苗顺德[2] 

机构地区：[1]"油气资源与探测"国家重点实验室.中国石油大学 [2]中国海洋石油研究总院 [3]中国石油新疆油田公司勘探开发研究院

出　　处：《天然气工业》2014年第11期26-35,共10页Natural Gas Industry

基　　金：国家高技术研究发展计划(863计划)项目“南海深水盆地油气资源形成与分布基础性研究”(编号:2009CB219400)

摘　　要：为了厘清深水区天然气成藏过程及其成藏控制因素,在对珠江口盆地白云凹陷荔湾3-1气田基本地质特征、天然气来源与成藏过程进行分析的基础上,开展了深水天然气成藏物理模拟实验,最终建立了白云凹陷的天然气成藏模式,明确了其成藏特征。实验研究的结果表明:1荔湾3-1断背斜型气田的形成与大断层的长期活动有着密切的关系,其天然气组成以烃类为主,非烃类含量很低,高成熟阶段的湿气垂向运移效应显著;2天然气伴生液态烃来自晚始新统—早渐新统恩平组和晚渐新统珠海组烃源岩,而天然气则以恩平组烃源岩来源为主,但早始新统文昌组烃源岩也有贡献;3白云凹陷天然气在早期由于断裂活动性较强,虽有运移,但以散失为主,晚期断裂活动逐渐减弱,天然气开始聚集成藏;4油气的垂向运移作用明显大于侧向运移作用,断裂沟通有效烃源岩与储集层的部位最有利于气藏的形成;5源—断—储时空晚期有效耦合是该区天然气成藏的关键;6圈闭距大断裂和烃源灶越近,越有利于天然气的晚期聚集,反之则天然气成藏效率明显降低。This paper aims to make a better understanding of geological features,gas sources,and the pool-forming process of the Liwan 3-1deepwater gas field in the Baiyun Sag,Pearl River Mouth Basin.A number of physical simulation experiments on gas reservoir formation were conducted and various gas accumulation patterns in the Baiyun Sag were established.The following findings were obtained.（1）The formation of the Liwan 3-1faulted anticline gas field was closely related with a long-term active giant fault,where natural gas was composed of a large number of hydrocarbons ＆fewer nonhydrocarbons,and the high-mature-stage wet gas had a clear vertical migration effect.（2）The associated liquid hydrocarbons in the gas there came from the source rocks in the Late Eocene– Early Oligocene Enping Fm and the Late Oligocene Zhuhai Fm,but natural gas mainly sourced from the Enping Fm with a tiny amount from the Early Neocene Wenchang Fm.（3）In the Baiyun Sag,natural gas migrated but scattered or disappeared at the early stage because of strong fault activities,but really started to accumulate and form reservoirs at the late stages due to the weakening fault activities.（4）In general,gas migration in the vertical direction is stronger than that in the lateral direction,agas reservoir easily formed in those zones where faults connect well between effective source rocks and reservoir beds.（5）The late-stage effective time-space coupling of source rock-fault-reservoir was a key to the formation of a gas reservoir in the Baiyun Sag.（6）The closer a trap is to a giant fault and hydrocarbon source kitchen,the more favorable for natural gas to accumulate at the late stage,otherwise the gas accumulation efficiency obviously decreases.

关 键 词：珠江口盆地 白云凹陷 荔湾3-1气田 深水区 气藏形成 模拟实验 源—断—储耦合成藏模式 

分 类 号：P618.13[天文地球—矿床学]