摘要
通过对东营凹陷古近系异常高压分布和砂岩透镜体成藏响应特征分析后认为:岩性油气藏发育的沙三段主要处于下部异常高压体系中;平面上,该高压体系的分布基本上与生油洼陷一致——北部陡坡带压力系数较高,南部缓坡带压力系数相对较低,这与欠压实发育带分布规律具有很好的一致性,也就证实了欠压实和泥岩成熟生烃作用是导致东营凹陷沙三段普遍超压的重要因素;包围在异常高压泥岩中的透镜体处于低势区,在泥岩和砂岩流体压力差异作用下,泥岩破裂,发生幕式排烃作用;砂体在烃类充注之后,也形成与烃源岩平面分布规律相似的较高的流体压力。
Lithological reservoirs are developed in below abnormal high-pressure system, by analyzing character of the distribution of pressure of early-Tertiary in Dongying Depression and its response to the lens' hydrocarbon accumulation. The distribution of abnormal high-pressure is in accord with source-subdepression in plane on the whole. Pressure coefficient is higher in north region and lower in south region, which is correspond with the distribution of undercompaction region. The main factors, which led to Es_3 abnormal high-pressure in Dongying depression, are undercompaction and hydrocarbon generation. Hydrocarbon accumulation of lens reservoirs are controlled by the distribution of abnormal high-pressure. Lens reservoirs, enveloped in dark mudstone, is mostly distributed in relative low-pressure region. Microfracture and episodic expulsion hydrocarbon of mudstone are generated by pressure difference between mudstone and lens. Sandstones have relative high fluid pressure after hydrocarbon filling.
出处
《天然气地球科学》
EI
CAS
CSCD
2004年第1期95-98,共4页
Natural Gas Geoscience
基金
国家"十五"攻关项目"济南坳陷复杂隐蔽油气藏地质评价和关键技术研究"(编号:2001BA605A09)资助.
关键词
凹陷
古近系
异常高压
成藏响应
幕式排烃
压力纵向分布
Dongying depression
Early Tertiary
Abnormal high-pressure
Episodic expulsion hydrocarbon
Response to hydrocarbon accumulation.
