天然气藏形成过程动态物理模拟——以柴北缘鄂博梁Ⅲ号构造为例  

Dynamic physical simulation of gas pool forming process:A case study of Eboliang Ⅲ structure in the north margin of the Qaidam Basin

作　　者：汤国民[1,2] 罗群[3] 庞雄奇[1] 向才富[1] 徐子远[4] 彭威龙 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室 [2]中海石油(中国)有限公司天津分公司勘探开发研究院 [3]中国石油大学(北京)非常规天然气研究院 [4]中国石油青海油田公司勘探开发研究院 [5]中国石油勘探开发研究院

出　　处：《天然气工业》2015年第9期24-34,共11页Natural Gas Industry

基　　金：国家重点基础研究发展计划(973计划)项目(编号:2011CB201100);国家重点基础研究发展计划(973计划)(编号:2015CB250900)

摘　　要：物理模拟实验是研究油气运聚的重要方法与手段,为改进、完善这一实验方法,在前人物理模拟实验成果的基础上,将构造挤压融入油气充注的实验过程中,并以柴达木盆地北缘鄂博梁Ⅲ号构造天然气藏为例,利用研发的天然气运聚成藏动态模拟实验装置,成功模拟了该构造天然气藏的形成过程,并进一步总结了该区气藏的形成规律。实验结果表明:①该区存在深、浅2套输导体系,深部输导体系为断裂—输导层输导体系,有利于天然气的向上运移并在优质储层中聚集成藏,而浅部输导体系为断裂—输导层—断裂输导体系,对浅部天然气藏具有破坏作用,不利于天然气的聚集成藏;②气藏形成后期,当供气量小于散失量时,气藏逐渐萎缩直至消失,由于深部地层的保存条件相对浅部更为优越,因此气藏消失的顺序也是先浅层后深层,由此形成了该区"浅差深好"的天然气藏保存序列。结论认为:鄂博梁Ⅲ号构造中深部可能存在保存较好的大型整装天然气藏。Physical simulation experiment is an important method and way to study oil and gas migration and accumulation. For the purpose of improving and perfecting this experimental method, tectonic compression was integrated into oil and gas charging experi- ment on the basis of previous physical simulation experiment results. In this paper, the Eboliang III structure in the north margin of the Qaidam Basin was taken for a case study, and its gas pool forming process was successfully simulated by using gas migration, accumulation and pool formation dynamic simulation experiment facilities. And moreover, the gas pool forming rules in this area were further summarized. Based on the experiment, there are two conduit systems in the deep and shallow layers respectively. The deep conduit system is a fracturing-carrier bed system, which is favorable for natural gas to migrate upward and accumulate in good reservoirs. However, the shallow one is a fracturing-carrier bed-fracturing system, which is destructive to shallow gas reservoirs and unfavorable for gas pool forming. During the late stage of gas pool formation, the gas reservoirs shrink gradually and finally disap- pear when the gas supply is less than the leakage. The preservation conditions in the deep reservoirs are better than those in the shal- low ones, so the gas reservoirs in the shallow beds disappear earlier than those in the deep beds. In this way, the gas reservoir pres- ervation sequence of being poor in the shallow beds and good in the deep ones was formed in this area. It is concluded that there are probably better-preserved large intact gas reservoirs in the middle-deep part of Eboliang III structure.

关 键 词：柴达木盆地北缘 鄂博梁Ⅲ号构造 气藏形成 物理模拟实验 输导体系 保存序列 构造挤压 勘探区 

分 类 号：P618.13[天文地球—矿床学]