马达班湾盆地某区块上新统砂岩成岩作用对储层的影响

Diagenesis and its influence on reservoirs of Pliocene in a block of Moattama Bay Basin

缅甸马达班湾盆地位于油气富集的弧后走滑拉张盆地构造位置,寻找有利储层成为该区油气勘探取得突破的关键。运用铸体薄片和X射线衍射等岩矿分析技术对缅甸马达班湾盆地某区块上新统砂岩储层岩石矿物特征和成岩作用进行了分析,认为研究区砂岩储层岩石类型主要为长石石英砂岩和岩屑石英砂岩,多为中等成熟。总体上,压实作用、胶结作用和溶解作用对研究区储层物性的影响均较小;研究区南部影响储层物性的主要因素为压实作用。研究区整体上破坏性成岩作用对孔隙度损失的影响较小,综合认为上新统具备形成油气储层的有利条件。

The Moattama Bay Basin is located in the back arc strike slip and extensional tectonic position with oil and gas enrichment, seeking favorable reservoirs become the key for the breakthrough of petroleum exploration in this area. By using techniques of casting thin section and X-diffraction, this paper analyzed mineral characteristics and diagenesis of Pliocene sandstone reservoirs in a block of Moattama Bay Basin. It is believed that the rock types of sandstone reservoir are mainly feldspar quartz sandstone and lithic quartz sandstone, with moderate maturity mostly. As a whole, the study area experienced diagenesis of compaction, cementation and dissolution, which influenced reservoir properties little. In the south of the study area, compaction is a main factor influences the reservoir properties dominantly. Destructive diagenesis has little effect on the porosity loss, so Pliocene formations possess advantages of forming hydrocarbon- bearing reservoirs in this area.