摘要
川中古隆起震旦系灯影组成藏过程复杂,油气藏成藏流体充注期次及演化历史恢复难度较大,前人对该地区古油藏成藏演化过程观点不一,从而制约了深层海相油气藏成藏规律的认识。文中以川中古隆起北斜坡蓬莱-中江地区为例,通过镜下岩相学观察、烃包裹体丰度测定、激光拉曼光谱分析、均一温度及盐度测定,对该地区流体包裹体进行了综合分析。结果表明:蓬莱-中江地区震旦系灯二段发育3期流体包裹体,早、中期以沥青包裹体为主,主要分布在孔洞早期充填的方解石及中期碳质沥青旁的白云石、石英中,晚期以气态烃包裹体为主,有少数气液烃包裹体和液态烃包裹体,次生在最晚形成的石英及方解石愈合缝中;研究区晚期气态烃包裹体丰度EGOI多大于3%,为含油层。通过对包裹体均一温度及盐度测试发现,研究区包裹体均一温度在80.6~231.4℃连续分布,在3个区间内出现了峰值,盐度范围主要为8%~20%。成藏过程分析表明:研究区共经历3期成藏,晚志留世形成Ⅰ期古油藏,中三叠世-晚三叠世形成Ⅱ期古油藏,侏罗纪-早白垩世原油裂解形成Ⅲ期古气藏;从晚白垩世至今,古气藏经过调整期逐渐定型。
The accumulation process of Sinian Dengying reservoir in central Sichuan Paleo-uplift is complicated,and it is difficult to recover the filling period and evolutionary history of reservoir accumulation fluid.Predecessors have different views on the evolution process of paleo-oil reservoir accumulation in this area,which restricts the understanding of the accumulation law of deep marine oil and gas reservoir.This study takes the Penglai-Zhongjiang area on the northern slope of central Sichuan paleo-uplift as an example,and comprehensively analyzes the fluid inclusions in the area through microscopic petrographic observation,hydrocarbon inclusion abundance measurement,laser Raman spectroscopy analysis,homogenization temperature and salinity determination.The results show that there are three stages of fluid inclusions developed in the second Member of Dengying Formation of the Sinian in the Zhongjiang area of Penglai.In the early and middle stages,asphalt inclusions are mainly distributed in the calcite filled with pores in the early stage and in the dolomite and quartz near the carbonaceous asphalt in the middle stage.In the late stage,fluid inclusions are mainly gaseous hydrocarbon inclusions,with a few gas-liquid hydrocarbon inclusions and liquid hydrocarbon inclusions which distribute in the most recently formed healing fractures in quartz and calcite.The abundance EGOI of late gaseous hydrocarbon inclusions in the study area is more than 3%,which is an oil-bearing layer.The homogenization temperature and salinity tests show that the homogenization temperature of inclusions in the study area is continuously distributed from 80.6℃to 231.4℃,and peaks appear in three sections,and the salinity ranges mainly from 8%to 20%.The analysis of reservoir accumulation process shows that there are three stages of accumulation in the study area.The first stage of paleo-oil reservoir was formed in the Late Silurian,the second stage of paleo-oil reservoir was formed in the MiddleTriassic to Late Triassic,and the third stage of paleo-oil rservoir was formed by crude oil cracking from the Jurassic to Farly Cretaceous;From the late Cretaceous to the present,the paleo-gas reservoir has been formed gradually through the adjustment period.
作者
宋嘉琦
肖晖
SONG Jiaqi;XIAO Hui(School of Earth Science and Engineering,Xi′an Shiyou University,Xi′an 710065,China;Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi′an 710065,China)
出处
《断块油气田》
CAS
CSCD
北大核心
2024年第5期762-770,共9页
Fault-Block Oil & Gas Field
基金
陕西省教育厅重点研究计划项目“高-过成熟度烷烃气碳同位素倒转成因分析——以鄂尔多斯盆地靖边气田为例”(17JS109)。
关键词
流体包裹体
油气成藏
灯影组
震旦系
川中古隆起
fluid inc lusion
oil-gas accumulation
Dengying Formation
Simi an
central Sichuan paleou plift
