苏里格气田下古低渗碳酸盐岩气藏有利区评价方法  

Evaluation method for favorable areas of lower palaeo-low permeability carbonate gas reservoir in Sulige gasfield

作　　者：范惠珺 田敏[2,3] 张波[2,3] 薛媛[2,3] FAN Huijun;TIAN Min;ZHANG Bo;XUE Yuan(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China;Exploration and Development Research Institute of PetroChina Changqing Oilfield Company,Xi'an Shaanxi 710018,China;National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields,Xi'an Shaanxi 710018,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [3]低渗透油气田勘探开发国家工程实验室,陕西西安710018

出　　处：《石油化工应用》2021年第9期74-80,共7页Petrochemical Industry Application

基　　金：中国石油天然气股份公司重大科技专项,项目编号:2016E-0509。

摘　　要：苏里格气田下古生界科斯特风化壳气藏是苏里格气田的兼顾开发对象,该类气藏具有储层薄、丰度低、非均质性强、局部地层水发育、气井产能差异大的特征;受开发方式及气藏地质特征影响,该类气藏开发过程中面临气层钻遇率低难题。勘探开发实践和研究成果认识,进一步明确古地貌是控制优质储层发育的关键、孔隙结构及局部微构造影响气水分布,三者共同控制下古气藏“甜点区”的分布;通过高产气井钻井岩心、薄片、储层物性参数、试气及生产动态效果统计对比分析,认为气、水层在品质因子(RQI)分布特征方面有相对明显的差异,斜坡带背景下的储能系数(hS_(g)φ)与气井产能具有明显的正相关性。基于该认识提出基于储层品质因子、储能系数两种参数进行有利区评价及预测,在苏X区块落实有利区125 km2,近两年实施下古气井25口,气层钻遇率由往年平均42.5%提高至67.5%,开发效果显著提升。The gas reservoir of lower paleozoic karst weathering crust in Sulige gasfield is the development object of Sulige gasfield,which is characterized by thin reservoir,low abundance,strong heterogeneity,local formation water development and large difference in gas well productivity.Affected by the development mode and the geological characteristics of gas reservoirs,this kind of gas reservoirs are faced with the problem of low drilling rate.According to the exploration and development practice and research results,it is further confirmed that palaeogeomorphology is the key to control the quality reservoir development,pore structure and local microstructure influence the distribution of gas and water,and they control the distribution of"sweet spot"of lower palaeo gas reservoir together.Based on the statistical and comparative analysis of drilling cores,thin sections,reservoir physical parameters,gas testing and production performance of high gas production wells,it is concluded that there are relatively obvious differences between gas and water layers in the distribution characteristics of quality factors(RQI),the Energy Storage Coefficient(hS_(g)φ)has a positive correlation with gas well productivity.Based on this understanding,the favorable area is evaluated and predicted by two parameters:reservoir quality factor and energy storage coefficient,the favorable area is 125 square kilometers in Su X block,and 25 lower paleozoic gas wells have been operated in recent years,the gas formation drilling rate is increased from 42.5%to 67.5%,and the development effect is improved significantly.

关 键 词：储能系数 品质因子 有利区预测 下古气藏 苏里格气田 

分 类 号：TE122.3[石油与天然气工程—油气勘探]