泰国呵叻盆地二叠系Pha Nok Khao组碳酸盐岩沉积相特征  

Facies Characteristics of a Permian Carbonate Platform of Pha Nok Khao Formation from Khroat Basin,Thailand

作　　者：胡双全 杜贵超[2] 甄胜利 

机构地区：[1]陕西延长石油(集团)有限责任公司研究院,西安710075 [2]西安石油大学地球科学与工程学院,西安710065 [3]陕西延长石油国际勘探开发工程有限公司,西安710075

出　　处：《沉积学报》2017年第4期789-796,共8页Acta Sedimentologica Sinica

基　　金：陕西延长石油(集团)有限责任公司科技研发项目(ycsy2014ky-A-10)~~

摘　　要：通过研究区3口钻井岩芯、测井、录井资料分析,结合薄片鉴定、阴极发光、X衍射、同位素及微量元素分析等分析手段,对呵叻盆地二叠系碳酸盐岩沉积相发育特征及沉积模式进行了系统分析。研究表明,呵叻盆地二叠系Pha Nok Khao组发育缓坡型无障壁碳酸盐台地沉积,研究区位于碳酸盐台地前缘斜坡部位,以海水浪基面为界,可划分为台地前缘浅水斜坡亚相及较深水斜坡亚相。浅水斜坡亚相指示沉积环境为位于浪基面以下或附近、水动力弱、弱还原—弱氧化的台地前缘斜坡环境;较深水斜坡亚相组合指示沉积环境为位于浪基面以下、水体较深、水动力弱、弱还原—中等还原的前缘斜坡环境。整体来看,研究区二叠系碳酸盐岩沉积时期主要为水体较深、水动力弱、垂向上沉积环境稳定的低能环境沉积。该沉积环境不利于形成良好的基质孔隙条件,有利储层发育主要取决于碳酸盐岩地层后期改造程度。Based on core data description,logging data analyses,thin section analyses,SEM observations,X-ray diffraction（ XRD） analysis,C/O isotopic analyses and trace element analyses,sedimentary facies and depositional environments of Permian carbonate rocks taken from Pha Nok Khao Formation of Khroat basin were systemacially examined. This study shows that the Permian depositional sequence belongs to carbonate ramp deposits with no barrier. The study area locates in the fore-slope area of carbonate platform,which can be divided into shallow water fore-slope sub-facies and relatively deeper water fore-slope sub-facies. The former indicates a weak hydrodynamic condition,weak oxidation-weak reduction environment,with depositional water depth below or around sea wave base within a slope environment. The latter indicates a relatively deeper water depth than the former. Its environment is characterized by weak oxidation-moderate oxidation environment,with its depositional water depth below sea wave base. The Permian carbonate stata in the study area is a typically low-energy depositonal sequence with a relatively deeper water depth and weak hydrodynamic condition,and the vertical evolution of sedimentary environment is stable. High-energy sedimentary facies does not develop in the study area,indicating that the basic conditions for favorable reservoir development possibly do not exist and the development of potential carbonate reservoirs in Pha Nok Khao Formation will be controlled by alteration of tectonic movements or diagenesis.

关 键 词：呵叻盆地 二叠系 碳酸盐岩 PHA Nok Khao组 沉积相 

分 类 号：P512.2[天文地球—地质学]