摘要
根据岩石薄片、扫描电镜、物性和测井等资料,分析了渤中凹陷A2-1构造东营组砂岩储层品质控制因素,探讨了测试段产能差异的原因。通过分析认为:渤中凹陷古近系东营组储层物性主要受压实作用、沉积条件、碳酸盐胶结、溶蚀作用和黏土转化阶段控制。在负胶结物投点图上,大部分砂岩都落在压实作用区间,显示了压实作用是减少孔隙的主要因素;沉积条件对储层物性的影响突出体现在粒度和泥质含量方面的影响,随着粒度变细、泥质含量增加,渗透率明显降低。储层中普遍含碳酸盐胶结物且含量较高,是DST2测试段渗透率低、产能差的重要原因之一。两测试段储层中溶蚀作用普遍存在,主要体现在对长石的溶蚀,DST2测试段是强超压的半封闭系统,溶出物不能有效带出系统而沉淀在孔隙和喉道中,对储层物性破坏较大。黏土转化阶段与渗透率的快速降低段有较好的对应关系,渗透率变差段主要出现在伊蒙混层有序混层带以下。
On the basis of thin section analysis, electron microprobe scanning, physical properties and logging data, this paper studies on controlling factors of reservoir in Paleogene Dongying formation of structure A2 - 1 in Bozhong Sag and discusses the reasons for different productions between the test sections. Through the analysis concerned, sandstone reservoir properties of Dongying formation in Bozhong Sag are mainly controlled by compaction, depositional environment, carbonate cementation, dissolution and clay transformation stage. In the minus-cement point diagram, most of the points are in the lower left corner, meaning compaction is the major factor of de- creasing porosity. Influence of depositional environment on reservoir properties reflected most outstandingly in respect of grain size and clay content. With decreasing of grain size and increasing of clay content, permeability is rapidly decreasing. Those are the major cau- ses of low yield. One of the reasons of low permeability and productivity of DST2 is that reservoirs generally contain carbonate cement. Dissolution which mainly reflected in the dissolution of feldspar generally exists in two test sections, DST2 test section is semi-closed system with strong overpressure, dissolving objects cant be effectively brought out from the system and deposit in pore and throat which destroyed reservoir properties a lot. Clay transformation stage has a good corresponding relationship with permeability, and permeability becomes worse when US（S% ） is less than 15%.
出处
《海洋石油》
CAS
2011年第4期59-62,67,共4页
Offshore Oil
基金
国家科技重大专项"近海富烃凹陷资源潜力再评价和新区
新领域勘探方向"(2008ZX05023-001-004)
中海石油(中国)有限公司天津分公司"十一五"重大基础研究项目"渤海湾地区古近系层序地层及隐蔽圈闭分布预测"(SC06TJ-TQL-004-BH02)
关键词
渤中凹陷
东营组
储层物性
控制因素
渤海湾盆地
Bozhong Sag
Dongying formation
reservoir properties
controlling factors
Bohai Bay Basin
