Control factors of reservoir oil-bearing difference of Cretaceous Mishrif Formation in the H oilfield, Iraq  

作　　者：ZHAO Limin ZHOU Wen ZHONG Yuan GUO Rui JIN Zhimin CHEN Yantao 

机构地区：[1]Chengdu University of Technology [2]Research Institute of Petroleum Exploration & Development,PetroChina [3]Research Institute of Petroleum Exploration and Development,Southwest Oil and Gas Field Company, PetroChina [4]State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University [5]Branch of Deposition and Accumulation, PetroChina Key Laboratory of Carbonate Reservoir, Southwest Petroleum University

出　　处：《Petroleum Exploration and Development》2019年第2期314-323,共10页石油勘探与开发（英文版）

基　　金：Supported by the China National Science and Technology Major Project(2017ZX05032004-001)

摘　　要：To reveal the law of oiliness of the Upper Cretaceous carbonate reservoirs in the Middle East and factors controlling the oiliness, the Mishrif Formation of the H oilfield in Iraq was examined comprehensively. Based on core observation and description, casting thin section analysis, and statistics of physical property and pore-throat structure parameter, etc., in combination with previous achievements and understanding, it is pointed out that the coring interval of Mishrif Formation has strong oiliness heterogeneity, and can be divided into 4 grades, oil rich, oil immersed, oil spot, and oil trace; the oil-bearing grade has obvious facies-controlled characteristic in macroscopic view; and in different oil-bearing grades, relatively oil-rich sections present higher karst development intensity, better physical properties and pore-throat structure characteristics. It is concluded through the study that the sedimentary microenvironment and eogenetic karstification determine the macroscopic oiliness of the reservoir in Mishrif Formation of H Oilfield, and the improvement of pore-throat structure caused by eogenetic karstification is the decisive factor of the micro oil-bearing difference of the reservoir. Finally,the genetic model of reservoir development and oil-bearing difference was established.To reveal the law of oiliness of the Upper Cretaceous carbonate reservoirs in the Middle East and factors controlling the oiliness, the Mishrif Formation of the H oilfield in Iraq was examined comprehensively. Based on core observation and description, casting thin section analysis, and statistics of physical property and pore-throat structure parameter, etc., in combination with previous achievements and understanding, it is pointed out that the coring interval of Mishrif Formation has strong oiliness heterogeneity, and can be divided into 4 grades, oil rich, oil immersed, oil spot, and oil trace; the oil-bearing grade has obvious facies-controlled characteristic in macroscopic view; and in different oil-bearing grades, relatively oil-rich sections present higher karst development intensity, better physical properties and pore-throat structure characteristics. It is concluded through the study that the sedimentary microenvironment and eogenetic karstification determine the macroscopic oiliness of the reservoir in Mishrif Formation of H Oilfield, and the improvement of pore-throat structure caused by eogenetic karstification is the decisive factor of the micro oil-bearing difference of the reservoir. Finally,the genetic model of reservoir development and oil-bearing difference was established.

关 键 词：carbonate reservoirs eogenetic KARSTIFICATION RESERVOIR OILINESS Mishrif FORMATION Upper CRETACEOUS Iraq 

分 类 号：TE[石油与天然气工程]