川中磨溪构造龙王庙组流体包裹体特征及其地质意义  

Characteristics and geological significance of fluid inclusions in Longwangmiao Formation of Moxi structure in Central Sichuan,China

作　　者：刘伟[1] 王国芝[1] 刘树根[1] 范蕾[1] 和秀蓉[1] 

机构地区：[1]油气藏地质及开发工程国家重点实验室(成都理工大学),成都610059

出　　处：《成都理工大学学报（自然科学版）》2014年第6期723-732,共10页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家重点基础研究发展计划"973"项目(2012CB214805);国家自然科学基金资助项目(41072082;41273060)

摘　　要：对四川盆地磨溪构造下寒武统龙王庙组储层中所充填石英与沥青的关系、石英中流体包裹体进行综合研究，探讨油气藏的成藏过程。通过对龙王庙组储层白云岩标本观察、石英中流体包裹体的镜下分析、显微测温表明，形成于石油热裂解后的石英流体包裹体主要为气液H2O包裹体、烃-H2O包裹体和纯甲烷包裹体。气液 H2O 包裹体的均一温度峰值为210-230℃，纯甲烷包裹体的密度为0．2148-0．2997 g／cm^3，流体的捕获压力为73．10-153．74 MPa，峰值为100．00-135．00 MPa，显示明显的超压特征。说明古气藏保存条件较好，现今气藏仍旧具有超压特征，应为古气藏经调整后重新聚集成藏的结果。This paper studies the relations between quartz and bitumen,and the fluid inclusions in the quartz from the Lower Cambrian Longwangmiao Formation of the Moxi structure, in order to approach the oil and gas accumulation process.The research result shows that the types of the fluid inclusions formed after the oil thermal cracking are saline aqueous inclusion,hydrocarbon-aqueous inclusion and methane inclusion.The peak homogenization temperature of saline aqueous inclusions is 210 - 230℃, and the density of methane inclusions is 0.2148 - 0.2997 g/cm^3 . Using the homogenization temperatures of saline aqueous inclusions as the trap temperature of methane inclusions,the calculated trap pressure of methane inclusions is 73.10-153.74 MPa,and the peak value is 100.00-135.00 MPa.The peak pressure shows the overpressure characteristics obviously. This indicates that the preservation conditions of the ancient gas pools in Longwangmiao Formation of the Moxi structure are relatively good.The gas pools nowadays have formed after the ancient gas reservoir was damaged.

关 键 词：磨溪构造 龙王庙组 流体包裹体 超压 成藏 

分 类 号：TE122.113[石油与天然气工程—油气勘探]