琼东南盆地中部隆起带断裂对天然气成藏的控制作用  

Controlling effect of faults in central uplift belt of Qiongdongnan Basin on natural gas accumulation

作　　者：何小胡 杜彦男 欧阳杰 任丽娟 李彦颖 吴孔友[2] 季芬 杨富财 HE Xiaohu;DU Yannan;OUYANG Jie;REN Lijuan;LI Yanying;WU Kongyou;JI Fen;YANG Fucai(Hainan Branch,CNOOC China Limited,Haikou 570100,China;School of Geosciences,China University of Petroleum(East China),Qingdao 266580,China;Shandong Jiaye Petroleum Technology Co.,Ltd.,Dongying 257000,China)

机构地区：[1]中海石油(中国)有限公司海南分公司,海南海口570100 [2]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [3]山东佳业石油科技有限公司,山东东营257000

出　　处：《断块油气田》2025年第2期201-210,共10页Fault-Block Oil & Gas Field

基　　金：国家自然科学基金项目“碳酸盐岩区走滑断裂带内部结构及启闭差异性研究——以塔里木盆地为例”(42272155)。

摘　　要：琼东南盆地中部隆起带断块圈闭中天然气成藏的有效性评价和控制因素分析是制约该地区油气勘探的主要因素之一。文中根据高精度三维地震资料和测、录井资料数据,选取研究区3个典型含气构造区,开展断裂对天然气成藏控制作用研究,改进了原有断裂封闭性评价方法,计算了断面正应力、泥岩削刮比、断面紧闭指数和断裂泥质充填率等参数,并利用加权赋值的数学模型确立了断裂侧向封闭指数和垂向封闭指数,明确了各含气构造区断裂封堵天然气的界限值,揭示了断裂控藏影响因素。研究认为:研究区断裂封堵天然气的界限值存在差异,其中崖城A地区断裂更易形成天然气的侧向封堵,而松涛C地区断裂垂向封闭性更好;NE向断裂侧向和垂向封闭性优于NW向和近EW向断裂,反向断块封闭性优于顺向断块;砂泥厚度比与断裂侧向、垂向封闭指数呈负相关关系,且与垂向封闭指数相关性更大。该研究结果对于预测含气区和含气区勘探潜力评价具有一定的指导意义。The effectiveness evaluation and controlling factor analysis of natural gas accumulation in fault-block traps in the central uplift belt of Qiongdongnan Basin are one of the main factors restricting the oil and gas exploration in the region.In this paper,high-precision three-dimensional seismic data and logging data are used to study the controlling effect of faults on natural gas accumulation in three typical gas-bearing structural areas of the study area.The original evaluation method for fault sealing is improved,and parameters such as fault normal stress,mudstone scraping ratio,fault sealing index and fault mud filling rate are calculated.The lateral and vertical sealing indices of faults are established using a weighted mathematical model to clarify the boundary values of natural gas sealed by faults in various gas-bearing structural areas,and the influencing factors of fault-controlled reservoirs have been revealed.The research suggests that there are differences in the boundary values for fault sealing of natural gas in the study area.Among them,faults in Yacheng A area are more likely to form lateral sealing of natural gas,while faults in Songtao C area have better vertical sealing.The lateral and vertical sealing of NE-oriented faults is better than that of NW-oriented and near EW-oriented faults.The sealing performance of reverse fault-blocks is better than that of forward fault-blocks.The thickness ratio of sand and mud is negatively correlated with the lateral and vertical sealing indices of faults,and has a greater correlation with the vertical sealing indices.The research results have certain guiding significance for predicting gas-bearing areas and evaluating the exploration potential of gas-bearing areas.

关 键 词：断裂发育特征 侧向封闭指数 垂向封闭指数 断裂控藏 琼东南盆地 

分 类 号：TE122[石油与天然气工程—油气勘探]