摘要
为了认识华庆地区长8油层组原油成藏过程,首次应用含氮化合物组成,结合该油层组剩余压力和流体包裹体特征,研究了原油充注点和运移方向、原油充注的动力特征、期次和时间,认为华庆地区长8油层组原油中咔唑类化合物的运移分馏效应显著,储层包裹体均一温度分布特征反映原油经历了3次运移期和充注期.研究结果表明:在横向上,原油样品中咔唑类化合物的绝对含量由南向北和由东向西减小,而咔唑类化合物异构体比值则由南向北和由东向西增加,反映了长8原油具有2个充注点和运移方向,即从研究区南部和东部充注,向北部和西部方向运移;在纵向上,从长7至长8、长10油层组,咔唑类化合物的绝对含量逐渐减小,而咔唑类化合物异构体比值则逐渐增大,反映了原油由上向下运移,即从长7油层组向长8运移.华庆地区长8原油这种充注点和运移方向与长7油层组和长8油层组之间的剩余压力差以及长8油层组剩余压力分布特征相一致.储层包裹体均一温度分布表现为3个显著的主峰温度,即80℃,100℃和120~130℃.根据盆地埋藏史和热史,推测原油注入长8储集层的地质时间为侏罗世末期-早白垩世晚期.
To understand the hydrocarbon accumulation process in Chang 8 subsection of the study area, based on the features of fluid inclusions and residual pressure in Chang 7 and Chang 8 subsections, this paper used the compositions of neutral nitrogen compounds for the first time to study crude oil charging sites and migration directions, crude oil charging dynamic characteristics, time and stages. The results show that the migration fractionation effect of carbazole compounds in Chang 8 subsection is significant. The homogenization temperature distribution of fluid inclusions demonstrates that the crude oil has experienced three stages of charging and migration. Horizontally, the absolute content of carbazole compound in crude oil decreases from south to north and east to west, but the isomer ratio shows an opposite increasing trend, indicating that there are two charging sites and migration directions in Chang 8 subsection, namely charging in the south and east of the study area and then migrating toward north and west, respectively. Vertically, the absolute content of carbazole compound reduces from Chang 7 to Chang 8 and Chang 10 subsections, but the isomer ratio gradually increases, indicating that the oil migrates top down from Chang 7 to Chang 8 subsection. The charging sites and migration directions of Chang 8 subsection are consistent with the residual pressure difference between Chang 7 and Chang 8 subsections and the residual pressure distribution in the Chang 8 subsection. The homogenization temperature of fluid inclusions in Chang 8 subsection exhibits three peak temperatures, which are 80, 100 and 120 to 130℃, reflecting the three stages of oil charging and migration. According to the thermal history and burial history of the basin, it is inferred that the geological time of crude oil charging into Chang 8 subsection is from late Jurassic to late period of early Cretaceous.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2017年第4期838-845,858,共9页
Journal of China University of Mining & Technology
基金
国家自然科学基金项目(41272125,41472121)
