利用储层流体包裹体确定鄂尔多斯盆地塔巴庙区块上古生界油气充注期次和时期

Using Fluid Inclusions of Reservoir to Determine Hydrocarbon Charging Orders and Times in the Upper Paleozoic in Tabamiao Block,Ordos Basin

流体包裹体是保存在储层中的微小流体样品,包含有丰富的地质信息。通过对鄂尔多斯盆地塔巴庙区块18口井的62块流体包裹体样品进行荧光观察和显微测温,认为该区上古生界地层共发生过6期流体活动,均与油气成藏有关,并以第二期—第六期的天然气充注为主。结合埋藏史分析可知,油气成藏分别发生在距今190～150Ma的早侏罗世中期—中侏罗世晚期,150～124Ma的中侏罗世晚期—早白垩世早期,124～101Ma的早白垩世早期—早白垩世中期,101～86Ma的早白垩世中期—早白垩世中末期和86～70Ma的早白垩世中末期—早白垩世末期。其中,早侏罗世中期—中侏罗世晚期为油气充注的初始阶段,中侏罗世晚期—早白垩世早期为轻质油的主要成藏时期,中侏罗世晚期至早白垩世末为研究区内目的层天然气的主要成藏时期。

Fluid inclusions are micro samples saved in reservoirs, which include a large amount of geological information. According to the observation of fluorescence colors and the measurement of homogenization temperatures of fluid inclusions obtained from 18 wells in the Upper Paleozoic of Tabamiao block in Ordos Basin, this paper points that there have happened six times of thermal fluid flow in the sandstone reservoirs of the Upper Paleozoic, all of which are relative to hydrocarbon chargings. By integrating the average homogenization temperatures with burial historical curves, the charging orders respectively correspond to the 190 -150 Ma（ the middle of the early Jurassic to the late of the Middle Jurassic period）, 150- 124 Ma（the late of the Middle Jurassic period to the early of the Early Cretaceous period）, 124 - 101 Ma（the early of the Early Cretaceous period to the middle of the Early Cretaceous period）, 101 - 86 Ma （the middle of the Early Cretaceous period to the middle-late of the Early Cretaceous period） and 86 - 70 Ma （the middle-late of the Early Cretaceous period）. In those periods, the middle of the Early Jurassic to the late of the Middle Jurassic period is the primary stage of hydrocarbon charging, the late of the Middle Jurassic to the early of the Early Cretaceous period is the main period of oil charging and the late the Middie Jurassic period to the late of the Early Cretaceous period is the gas charging time in the favorable target beds.