桩海地区下古生界古潜山碳酸盐岩储层非均质特征及成因

Carbonate pore characteristic and genesis of reservoir heterogeneousness of Paleozoic in Zhuanghai area

桩海地区下古生界潜山碳酸盐岩储层表现出极强的非均质性。主要表现为储集空间构成、储层与非储层配置关系和储集能力等方面。研究表明,岩性是研究区储层非均质性的基础;早期的溶蚀孔隙和潜山内幕储层与多级不整合面古岩溶作用密切相关;深埋藏溶蚀作用对碳酸盐岩次生孔隙的后期溶蚀及太古界与下古生界统一油水界面和二者相同的溶蚀特征的形成具重要影响;构造运动和埋藏溶蚀作用则能够合理解释下古生界古潜山带"上缝下洞"的储集空间分布特征及下古生界井段泥浆放空与标准风化壳模型中的孔隙度模式不匹配情况;地层条件下压力和温度对碳酸盐岩储层物性的影响导致研究区白云岩储集能力远高于灰岩。

The reservoir of Paleozoic carbonate in Zhuanghai area represents strong heterogeneousness. The carbonate heterogeneousness of research area primarily includes porosity construction, distribution of reservoir-nonreservoir and accommodation capacity. Research results indicate that lithologic character is the basis of carbonate heterogeneousness. Multistage unconformity karsts lead to early stage corrosion pore and the inside reservoir of buried-hill. Deep-buried karsts cause the formation of deep corrosion pore space and leads to uniform oil-water boundary and same erosion characters between Archean and Paleozoic. Tectonic movement and deep-buried karsts together result in the ＂upper fissureunder hole＂ reservoir character of buried-hill and can be used to particular the disagreement between the emptying of Paleozoic and the pore model in prototype karst. The Influence of pressure and temperature on the carbonate physical features causes the reservoir capacity of dolomite higher than that of limestone.