沾化凹陷沙河街组砂岩透镜体表面与内部碳酸盐胶结作用的差异及其成因  

Carbonate cementation difference and its origin between exterior and interior surfaces of lenticular sandbody in Shahejie Formation of Zhanhua Depression

作　　者：孙海涛[1,2] 钟大康[1,2] 刘洛夫[1,2] 张思梦[1,2] 

机构地区：[1]中国石油大学资源与信息学院,北京102249 [2]中国石油大学油气资源与探测国家重点实验室,北京102249

出　　处：《石油学报》2010年第2期246-252,共7页Acta Petrolei Sinica

基　　金：国家自然科学基金项目(No.40672094)资助

摘　　要：对沾化凹陷沙河街组不同分布模式的砂岩透镜体内部和表面砂岩和泥岩的密集采样进行了薄片、X射线衍射、扫描电镜和阴极发光分析,探讨了砂泥岩界面附近与透镜体内部的碳酸盐胶结作用的差异及其成因。研究表明,这种差异随透镜体的埋藏深度以及砂岩、泥岩各自的厚度变化而变化。无论是孤立式透镜体,还是叠加式透镜体,当砂体厚度超过2m、泥岩厚度超过5m时,砂、泥岩界面的晚期碳酸盐胶结程度高于砂体内部。透镜体在埋藏过程中形成的大量次生孔隙,以及晚期成岩作用阶段砂泥岩之间存在的单向或双向流体(物质)传递,是晚期碳酸盐矿物能否在透镜体表面(或薄砂体内部)大量胶结的重要条件。The thin section,X-ray diffraction,scanning electron microscopy and cathodo-luminescence micrography were used to analyse the origin of carbonate cementation difference between the exterior and interior surfaces of the lenticular sandbody in Shahejie Formation of Zhanhua Depression by high density sampling in the lenticular sandbodies of diverse distribution patterns and near the sand-shale contact.The analyses showed that the difference of carbonate cementation changed with the buried depth of lenticular sandbody and the thickness of sandbody and shale.When the thickness of sandbody with different patterns is up to 2m and the thickness of shale is up to 5m,the later carbonate cementation can be developed near the sand-shale contact.The carbonate cementation of the exterior surface is bigger than that of the interior surface of the lenticular sandbody.All the later carbonate cementations are resulted from the secondary porosity formed during the early burial phase and the directional or bidirectional transfer of fluid and mass in the later diagenetic phase.

关 键 词：沾化凹陷 沙河街组 砂岩透镜体 碳酸盐胶结作用 物质传递 

分 类 号：TE112.2[石油与天然气工程—油气勘探]