渤海海域蓬莱19-3油田油气成藏特征新认识  

New understandings of hydrocarbon accumulation in Penglai 19-3 oilfield,the Bohai waters

作　　者：郭永华 周心怀 凌艳玺 李建平 王飞龙 王军 

机构地区：[1]中国海洋石油(中国)有限公司天津分公司渤海油田勘探开发研究院,天津300452

出　　处：《石油与天然气地质》2011年第3期327-332,共6页Oil & Gas Geology

基　　金：国家科技重大专项(2008ZX05023-001-004)

摘　　要：蓬莱19-3油田是中国近海海域迄今发现的最大油田,油气来源和晚期超大规模成藏研究是其发现以来地质家不断研究和争论的焦点。研究认为:1)蓬莱19-3油田原油主要源于沙河街组烃源岩,部分源于东营组(渤中凹陷为主)烃源岩。油田周边存在两个非常明显的油气充注方向,即:油田的北西方向(渤中凹陷)和东南方向(庙西凹陷)。2)渤中凹陷极为丰富的油源、长期的低势区和郯庐断裂的能量释放以及以不整合面为主导输导体系的优势成藏模式是蓬莱19-3油田形成的先决条件。3)油藏内部井间温度的显著差异、原油密度、粘度和气体的变化规律,以及直至海底的‘气烟囱’较大面积存在等,说明油藏油气源非常充足,油田北侧至今存在超强充注,晚期成藏特征明显。证实了蓬莱19-3油田是渤海海域一种典型的晚期大规模快速成藏类型。As the biggest oilfield discovered offshore China so far,the Penglai 19-3 oilfield has aroused constant debates on oil sources and characteristics of massive-scale hydrocarbon accumulation in the late stage.From this study,we have brought up with three new understandings.First,oil in the Penglai 19-3 oilfield mainly originates from the source rocks in the Shahejie Formation and partially from source rocks in the Dongying Formation（in the Bozhong sag）.Hydrocarbons charged reservoirs from two apparent directions,i.e.,the NW direction（from the Bozhong sag） and the SE direction（from the Miaoxi sag）.The favorable factors for the development of the Penglai 19-3 oilfield are extremely abundant oil source in the Bozhong sag,long-existing low-potential energy area and the energy release from the Tan-Lu Fault as well as favorable carrier system dominated by unconformities.Third,The significant differences of interwell temperature,change patterns of oil density,viscosity and gases and large-scale existence of ＂gas chimney＂ rooted in ocean floor reveal that this oilfield is obviously characte-rized by abundant hydrocarbon sources and late hydrocarbon accumulation.Oil charging is still intensive in the northern part of the field at present.All leads to the conclusion that the Penglai 19-3 oilfield is a typical massive-scale,rapid hydrocarbon accumulation in the late stage in Bohai Sea.

关 键 词：生物标志化合物 郯庐断裂 气烟囱 新近系油藏 晚期成藏 蓬莱19-3油田 渤海海域 

分 类 号：TE112.3[石油与天然气工程—油气勘探]