阿姆河右岸盐下断裂复杂化礁滩相气藏特征及勘探意义——以BP气藏为例  

Features of gas reservoirs in subsalt faulted reef complex in the right bank of the Amu Darya River,Turkmenistan,and their significance in exploration:A case study of the BP gas reservoir

作　　者：聂明龙[1,2] 徐树宝 吴蕾 何金有[2] 明海会 张瑞[1] 

机构地区：[1]辽宁工程技术大学 [2]中国地质大学(北京)能源学院 [3]中国石油(土库曼斯坦)阿姆河天然气公司 [4]中油国际曼格什套有限责任公司

出　　处：《天然气工业》2015年第6期24-29,共6页Natural Gas Industry

基　　金：国家科技重大专项"阿姆河右岸中区天然气开发示范工程"(编号:2011ZX-05059);国家科技重大专项"中亚地区重点含油气盆地研究"(编号:2011ZX05029-003)

摘　　要：盐下礁滩体是阿姆河盆地东北部斜坡带阿姆河右岸地区油气勘探的主要对象。由于该区盐膏岩具有复杂的变形特征,加之构造运动形成的复杂断裂给气藏类型的识别带来了很大困扰。为正确认识这种断层与礁滩体叠置形成的复杂气藏,以BP气藏为例,通过对地震、试气、测井及天然气组分等资料和地层压力系统的综合分析,研究了该区气藏的类型及其形成模式。结果表明:①BP气藏的礁滩体被断裂切割,具有统一的气水界面和地层压力系统,是盐下礁滩相碳酸盐岩块状气藏;②盐下基底正断层在晚期构造运动中重新活动,由于断距小于背斜构造圈闭幅度,盐膏岩未能形成侧向遮挡,再加上断层多期活动形成的裂缝增强了储层的连通性,使得断层两侧对接的礁滩相碳酸盐岩储层互相连通,由此形成了被断裂所复杂化的整装背斜构造气藏;③在盐下断裂发育区,礁滩体很难单独成藏,油气藏的发育一般受构造控制,构造与礁滩体叠置区油气最为富集。所取得的成果和认识突破了过去"一礁一藏"的观点,明确了应以寻找构造气藏为主的天然气勘探思路。Subsalt reefs are major exploration targets in the right bank of the Amu Darya River, Turkmenistan. Complicated features related to the deformation of salt gypsum rocks, together with complex faults generated by structural movements, bring about significant challenges for the determination of gas reservoir types within this area. Accordingly, it is necessary to gain a deeper under standing of those complicated gas reservoirs generated through the superimposition of faults and reefs. In a case study of the BP gas reservoir in this study area, seismic, trial gas production, logging, natural gas composition data and formation pressure system were reviewed comprehensively to determine classifications and formation patterns of natural gas reservoirs there. The following research results were obtained. （1） Cut by faults, reefs in the BP gas reservoir has a uniform GWC and formation pressure system. Accordingly, the BP gas reservoir can be classified as a massive carbonate gas reservoir in subsalt reefs. （2） Normal faults in the subsalt basement were reactivated in late stage structural movements. With fault displacements lower than trap amplitudes of anticline strut tures, salt gypsum rocks failed to generate effective lateral sealing. In addition, fractures generated in the multi-stage movements of faults significantly enhanced the connectivity of reservoir formations to establish communication between reef carbonate reservoir for mations on both sides of the fault. In this way, un-eompartmentalized gas reservoirs in anticline structures with complicated structures induced by faults were generated. （3） In the areas with subsalt faults, gas reservoirs can hardly form in reefs. Generally speaking, the development of reservoirs is controlled by structures with maximum hydrocarbon accumulations in such areas with the superimposition of structures and reefs. Relevant research conclusions may clarify principles for natural gas exploration to focus on structural gas reservoirs instead of the ＂one reef, one rese

关 键 词：阿姆河盆地 右岸 礁滩体 盐下 断裂复杂化 块状气藏 构造特征 地层压力系统 地质成因 

分 类 号：P618.13[天文地球—矿床学]