莺歌海盆地乐东地区石英裂隙内流体包裹体特征及其对天然气成藏制约

莺歌海盆地乐东地区是我国典型高温超压天然气勘探领域，其关键储层黄流组砂岩以天然气富含CO₂为特征，对其中石英颗粒内裂隙包裹体的研究能为CO₂来源和天然气成藏信息提供重要线索。本文通过对黄流组砂岩石英颗粒内包裹体进行岩相学、显微测温与激光拉曼分析，结果表明黄流组砂岩石英颗粒内正常捕获流体包裹体均一温度主要分布在155~165益与170~180益两个温度区间，流体包裹体成分为CO₂（气）和H₂O（液）两种或CO₂（气）和CO₂（液）、H₂O（液）三种。这些特征表明乐东地区黄流组至少经历两期富含CO₂的热液活动，记录了埋藏晚期无机CO₂在火山活动或深大断裂发育期充注成藏的信息。

Characteristics of fluid inclusions in quartz fractures in Ledong area of Yinggehai Basin and its constraints on gas accumulation

Ledong area in Yinggehai basin is a typical field of high temperature and overpressure gas exploration in China. A large number of fluid inclusions are trapped in the quartz grains of sandstones in Huangliu Formation. Studying its characteristics and composition can analyze the information of gas accumulation in this area. According to the petrography,micro temperature measurement and laser Raman analysis of fluid inclusions,there are two types of fluid inclusions in the Huangliu formation quartz grain fracture: homogeneous and heterogeneous capture. The normally trapped fluid inclusions are mainly distributed between 155-165℃ and 170-180℃,and the compositions of fluid inclusions are CO2 (gas) and H2O (liquid) or CO2 (gas) and CO2 (liquid) and H2O (liquid). The characteristics of fluid inclusions indicate that the Huangliu formation in Ledong area experienced at least two periods of CO2 rich hydrothermal activity,recording the information of inorganic CO2 filling and reservoir formation in the late burial stage during volcanic activity or deep fault development.