通过对琼东南盆地东部研究区6口井的37块流体包裹体样品进行荧光观察和显微测温,认为该区共发生过4期与油气成藏有关的流体活动,结合埋藏史分析可知,油气成藏分别发生在距今20～18 Ma的早中新世、10～6.5 Ma的晚中新世、5.5～2 Ma的上新世和2～0 Ma的第四纪,其中第三期和第四期为主成藏期.第一期为成熟热成因气充注;第二期为低成熟度油伴随低成熟天然气充注;第三期为中等偏高成熟度的天然气充注,伴随少量凝析油充注;第四期为成熟-高成熟的天然气充注,伴随少量成熟的轻质油.此外,局部构造有幔源CO2气自中中新世(14 Ma左右)开始充注持续至今,对晚期烃类气体的运移和聚集有阻碍.%In this paper, 37 fluid inclusion samples from 6 wells in the eastern area of Qiongdongnan Basin have been employed to systematically obtain information including the observation of fluorescence colors and the measurement of homogenization temperatures, and the results indicate that there are four phases of thermal fluid flow relative to hydrocarbon chargings in the area. Integrated the average homogenization temperatures with burial historical curves, this paper concluded that the charging orders respectively correspond to 20 - 18 Ma( Early Miocene), 10-6.5 Ma (Late Miocene), 5.5 -2 Ma (Pliocene) and 2-0 Ma (Quaternary). In those periods, Pliocene and Quaternary are the primary stages of hydrocarbon charging. The first period fluid is mature thermogenic gas, the second one is low mature oil and gas, the third one is moderate and high mature gas and lease condensate, and the fourth one is mature-high mature gas accompanying a little mature light oil. Furthermore, mantle-source carbon dioxide has charged in local area since Middle Miocene ( 14 Ma), which hindered hydrocarbon migration and accumulation in late-stage.
展开▼
