高邮凹陷阜宁组一段储层成岩环境演化的流体包裹体证据

Evolution of Diagenesis Environment of the 1st Member Funing Formation in Gaoyou Sag:Evidence from Fluid Inclusions

在对苏北盆地高邮凹陷阜宁组一段储层岩心薄片的大量观察和分析基础上,对与阜一段储层成岩作用有关的流体包裹体进行了系统分析,明确了成岩作用流体性质.根据流体性质可以分为四个重要成岩流体活动阶段：①早期弱碱性流体活动,成岩温度50～80℃；②成岩流体演变为酸性.成岩温度80～105℃：③成岩流体演变为碱性,成岩温度95～120℃；④成岩流体演变为酸性,成岩温度110～140℃.碱性流体活动时期发生碳酸盐胶结,酸性流体活动期发生硅质胶结（石英次生加大）.酸性流体对次生孔隙的发育有利,由于成岩演化历史过程中酸性流体有限,其活动区域应当重点分析.

Based on observation and analysis of rock flakes from the 1^st member Funing Formation in Gaoyou Sag, the fluid inclusions connected with diagenesis （the character and stages of diagenesis fluids） were analyzed systematically. The results show that the 1^st member Funing Formation mainly underwent four stages of diagenesis environment according to fluids characteristics. The first stage was alkalescent diagenesis fluid, with the diagenesis temperature from 50 to 80 ℃ ; the second stage was acidic fluid with the diagenesis temperature from 80 to 105 ℃ ; the third stage was alkaline fluid with the diagenesis temperature from 95 to 120 ℃ , and the last stage was acidic fluid with the diagenesis temperature from 110 to 140 ℃. Carbonate cementation occurred when alkalescent fluid appeared, while silica cementaion （quartz overgrowth） mainly occurred in stage of acidic fluid movement. In addition,acidic flu id was beneficial to the formation of secondary hole in reservoir, but its quantity was very limited in the history of di agenesis,so it was important to determine its activity area.