新疆富蕴盆地南明水组暗色泥岩沉积环境演化及其页岩气地质特征  

Sedimentary environment evolution and shale gas geological features of dark mudstone from Nanmingshui Fm of Fuyun Basin,Xinjiang

作　　者：熊小辉[1,2] 王剑[1,2] 熊国庆[1,2] 余谦[1,2] 陆俊泽[1,2] 周继兵 白洪海 邓奇[1,2] 

机构地区：[1]成都地质调查中心,四川成都610083 [2]国土资源部沉积盆地与油气资源重点实验室,四川成都610083 [3]新疆地矿局第9地质大队,新疆乌鲁木齐830009

出　　处：《煤炭学报》2016年第6期1476-1486,共11页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(华南新元古代"楔状地层"沉积充填序列及大地构造研究)(41030315);新疆自治区地勘基金资助项目(N13-4-XJ02);扬子北缘新元古代花山群火山-沉积序列及其构造属性研究资助项目(41402103)

摘　　要：为了查明新疆北部富蕴盆地萨尔布拉克地区南明水组多套暗色泥页岩沉积环境演化、页岩气资源前景及两者内在的制约关系,进行了有机、无机地球化学及矿物学等分析,表明南明水组暗色泥岩沉积水体早期可能受大型河流影响明显淡化,后期开放性降低,盐度逐渐升高和恢复。暗色泥岩沉积时期气候总体温暖潮湿,中晚期温度稍有上升,较早期相对干旱,水体深度自下而上呈现由深变浅再变深的趋势,总体还原,向上还原性减弱。第2亚组生物生产率及总有机碳含量（介于0.42%-1.11%）均最高,有机质类型基本以Ⅲ型干酪根为主,含少量II2型干酪根,成熟度达到高—过成熟阶段。矿物成分以黏土矿物和石英为主,尤其是第2亚组（黏土矿物：32%-49%;石英：33%-41%;伊利石占黏土总量：61%-77%）,具备页岩气发育条件。对比分析显示,海陆交互区半咸水偏咸水的盐度条件、缺乏大型入海河流的干扰、稳定的沉积环境等更有利于产气页岩的发育。To understand the sedimentary environment evolution,shale gas prospect and their relationship of Nanmingshui Fm dark mudstone from Shaerbulake Region,Fuyun Basin,the analysis on inorganic,organic geochemistry and mineralogy were performed. It shows that,influenced by large rivers import,water desalination occurred during the sedimentation. Water openness decreased later,and the salinity re-increased gradually. It was warm and moist generally,then became warmer and drier in middle-late stage during Nanmingshui Fm sedimentation. There was a deep-shallowdeep change in water depth upward Nnmingshui Fm. Reducing condition occurred during dark mudstone sedimenta-tion,but it weakened upward Nanmingshui Fm. The organic matter is dominated by type Ⅲ with a few type II2,and its evolution is in a high-over maturation. The second member of Nanmingshui Fm bears highest biological production and total organic matter（ TOC： 0. 42%-1. 11%）. Mineral composition is dominated by clay and quartz,especially in the dark mudstone from the second member（ clay： 32%- 49%; quartz： 33%- 41%; illite in clay： 61%- 77%）,which have good factors for shale gas development. The study shows that brackish water with salinity lean to salt water,lack of large river import,stable sedimentary environment etc. are more beneficial to the development of gas-producing shale.

关 键 词：页岩气 沉积环境 地球化学 南明水组 富蕴盆地 

分 类 号：P618.13[天文地球—矿床学]