伊拉克哈勒法耶油田中、上白垩统碳酸盐岩储层岩石类型及特征  

Rock types and characteristics of the Middle-Upper Cretaceous carbonate reservoirs in Halfaya oilfield,Iraq

作　　者：王昱翔[1] 周文[1] 郭睿[2] 伏美燕[1] 沈忠民[1] 赵丽敏[2] 陈文玲[1] 

机构地区：[1]成都理工大学油气藏地质及开发工程国家重点实验室,四川成都610059 [2]中国石油勘探开发研究院,北京100083

出　　处：《石油与天然气地质》2016年第5期764-772,共9页Oil & Gas Geology

基　　金：中国石油天然气股份有限公司"十二五"重大专项(2011E-2501)

摘　　要：伊拉克哈勒法耶油田中、上白垩统碳酸盐岩储层是重要的产油层系。综合利用岩心、薄片、物性测试、压汞数据及扫描电镜分析资料,以典型取心井为研究对象,开展研究区岩石类型及特征研究。结果表明,岩石矿物成分主要为方解石和泥质,局部含少量白云石。岩石组分多样,各组分相对含量差异明显。在岩石组分类型及特征研究基础上,以泥晶基质、有孔虫骨架和生屑/砂屑为三端元,提出研究区岩石类型划分方案。将研究区岩石划分为泥晶灰岩、有孔虫灰岩和生屑/砂屑灰岩3大类,并进一步根据颗粒含量的多少将岩石类型划分为9小类。不同岩石的孔隙类型、孔隙结构和物性特征均不相同,是不同沉积环境的产物,储集性能差异较大。总体来看,平面上不同岩石类型分布明显受沉积环境控制。纵向上,有孔虫灰岩集中分布在上白垩统碳酸盐岩储层,厚度较大,生屑/砂屑灰岩分布较为局限,中白垩统碳酸盐岩储层多为生屑/砂屑灰岩。泥晶灰岩以薄层状分布在生屑/砂屑灰岩之间,有孔虫灰岩类罕见。The Middle-Upper Cretaceous carbonate reservoirs are the main pay zones in Halfaya oilfield of Iraq.Comprehensive analyses of cores,thin sections,physical property test results,mercury injection data and scanning electron microscopy （SEM） images were carried out on samples from typical coring wells in the reservoirs of the field to figure out rock types and characteristics in them.The results show that the mineralogy of the rocks is dominated by calcite and clay,with small amount of dolomite scattered locally.Components and their relatively contents in rocks vary greatly.Based on rock component types and characteristics,we constructed a three end-member framework with micritic matrix,foraminifera skeleton and bioclast/calcarenite limestone as each end-member,respectively,and proposed a classification scheme for rock types in the field.According to the scheme,the rocks can be categorized into three major classes （micrite,foraminifer limestone and bioclastic limestone/calcarenite） and nine sub-classes based on the contents of certain grains in the rocks.Different types of the rocks are observed to have various pore structure and physical characteristics-footprints of different sedimentary settings.Horizontally,the distribution of different types of rocks shows clear evidence of being controlled by sedimentary settings.And vertically,foraminifera limestone of greater thickness seems to be concentrating more on the Upper Cretaceous carbonate reservoirs.Bioclastic limestone/calcarenite was rather confined within certain areas and the Middle Cretaceous carbonate reservoirs contained mostly bioclastic limestone/calcarenite.Micrite is seen interbedded as thin layers in bioclast/calcarenite.And foraminifera limestone is rare.

关 键 词：岩石类型 碳酸盐岩 中、上白垩统 哈勒法耶油田 伊拉克 

分 类 号：TE122.2[石油与天然气工程—油气勘探]