新疆乌苏地区新近系石膏脉特征及形成过程  

Characteristics and Forming Process of the Neogene Gypsum Veins in Wusu Area,Xinjiang

作　　者：杨少春[1] 赵晓东[1,2] 刘桓 向奎[4] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266580 [2]中国石油冀东油田勘探开发研究院,唐山064300 [3]中国石油川庆钻探工程公司井下作业公司,成都610051 [4]中国石化胜利油田新疆勘探项目管理部,东营257017

出　　处：《高校地质学报》2014年第3期425-432,共8页Geological Journal of China Universities

基　　金：国家科技重大专项课题(2011ZX05009-003);中央高校基本科研业务费专项资金(13CX06013A)共同资助

摘　　要：基于野外地质调查及采集样品的微观分析,文中详细研究了新疆乌苏地区新近系发育的石膏脉特征,并从古沉积环境、成岩作用、风化作用和溶盐水注入期次等方面分析了石膏脉的形成过程。该区石膏脉发育形态特殊,主要是由两横两纵4条线状主控石膏脉派生出的各种产状石膏脉组成,呈龟壳状。通过分析认为该石膏脉的形成过程共经历过4个阶段,炎热的古沉积环境为沉积大量的石膏矿物奠定了基础,先成岩后胶结的成岩作用为石膏脉形成提供了必要条件,加上强烈的风化作用和多期地表溶盐水注入和析出,形成了现今的龟壳状结构石膏脉。该套石膏脉的存在为推测盆地中心可能存在天然储层裂缝改造区提供线索,并对西北地区新近纪干旱沉积环境具有一定的指示意义。Based on field geological investigations and microscopic analysis of samples, this paper analyzed the characteristics of the Neogene gypsum veins in Wusu area in detail. Also, the forming process of gypsum veins is analyzed by examining the ancient sedimentary environment, diagenesis, weathering, and saline solution injection. The gypsum veins of this area were very special because they were mainly composed of various secondary gypsum veins that were derived from two vertical and two horizontal linear master gypsum veins, displaying a turtle-shell-like geometry. The study shows that the forming process includes 4 stages. Ancient warm deposition environment is needed for depositing abundant gypsoide. Diagenesis is necessary for the gypsum formation. Furthermore, the strong weathering and multi stages of injected saline solution precipitation lead to the formation of the turtle-shell-like geometry of gypsum veins. The findings of this gypsum may provide clues for predicting that the central part of the northern sedimentary area where naturally fracture-affected reservoir may exist. It may also be used to indicate arid sedimentary environment of the Neogene strata in the northwestern region.

关 键 词：乌苏地区 新近系 龟壳状 石膏脉 

分 类 号：P512.2[天文地球—地质学]