摘要
通过对岩芯、岩石薄片的观察,运用扫描电镜、X衍射等分析方法,对永北地区沙三、四段砂砾岩储层进行了成岩作用研究,揭示了成岩作用对永北地区砂砾岩体储层物性的影响。认为胶结作用是储层物性变差的主要因素,胶结损孔率平均值高达43.95%;压实作用一方面导致储层原生孔隙减小,储层物性变差,另一方面强烈压实产生的大量粒内压裂缝,对砂砾岩储层物性具有一定的优化作用,但以损失原生孔隙为主,压实损孔率平均值为25.29%;溶蚀作用形成的次生孔隙为该储层主要的储集空间。有机质热演化、淋滤作用和异常高压所导致的溶蚀作用是该区次生孔隙形成的主要原因。
In order to understand the influence of pore evolution and diagenesis on sandstone and conglomerate reservoir petrophysical property of the third and fourth members of shahejie formation in yongbei area,reservoir rock property and diagenesis are studied by using the methods of core and rock tine section observation,electron microscope scanning and X-diffraction analysis.It is revealed that cementation destroys the reservoir property and dissolution improves it.Compaction result in primary pore decreasing,on the other hand,high pressure result in mineral grain breaking,so physical properties of reservoirs are improved.The loss ratio of porosity from the cementation and filling is about 43.95%,and that from compaction is about 25.29%.The secondary pores account for a great proportion in the Es3-Es4 reservoirs.The mechanism of genesis includes thermal evolution of organic matter,experiment indicates that the thermal degradation makes kerogen produce a large amount of organic acid before it goes into the oil-generation windows,eluviations at unconformities or fracture zones produce weathering crust secondary pores,the fluid thermal cycle convection leads to the formation of secondary pores.
出处
《西南石油大学学报（自然科学版）》
CAS
CSCD
北大核心
2008年第4期19-23,共5页
Journal of Southwest Petroleum University(Science & Technology Edition)
基金
国家自然科学基金项目(409972037)
关键词
储层
成岩作用
有机质热演化
淋滤作用
异常压力
东营凹陷
reservoir
diagenesis
thermal evolution of organic matter
leaching action
abnormal pressure
Dongying Sag
