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采用光学显微镜、扫描电镜、电子探针及 X射线衍射观察分析了塔里木盆地中新生界储层砂岩自生矿物及其在岩石中的产状 .形成于同生成岩期的自生矿物有海绿石 ,赤铁矿～褐铁矿和部分绿泥石 .浅埋藏期以碳酸盐～沸石～硬石膏组合为特征 .部分层位有自生高岭石 .在深埋藏期 ,以钠长石化为代表的水岩反应较活跃 ,蒙皂石向伊利石、绿泥石的转变亦主要发生在该期 .根据自生矿物与粘土矿物组合 ,在塔里木中新生界碎屑岩中可以识别出两种成岩环境 .上侏罗纪至第三系为碱性成岩环境 ,隙间流体继承了封存同生水特征 ,为碱性盐卤水 .三迭系至中下侏罗纪煤系为酸性成岩环境 ,它们在成岩过程中释放的有机酸使隙间流体呈酸性 .两种环境下形成的自生矿物组合截然不同 .成岩环境在一定程度上影响了水岩反应及次生孔隙发育
The authigenic minerals and their occurrences in the rocks of the Mesozoic and Cenozoic reservoirs in the Tarim Basin were observed by light microscopy, scanning electron microscopy, electron probe and X-ray diffraction. The authigenic minerals formed during the synsedimentary period include glauconite, Hematite to limonite and some chlorites.The shallow burial period is characterized by carbonate-zeolite-anhydrite assemblage, some of which have authigenic kaolinite, and the deep-burial period is represented by albite The water-rock reaction is more active, and the change of smectite to illite and chlorite occurs mainly during this period.According to the combination of authigenic mineral and clay mineral, two diagenetic environments can be identified in Cenozoic clastic rocks in Tarim Basin. The Upper Jurassic to the Tertiary are alkaline diagenetic environments, and the interstitial fluid inherits the characteristics of sealed-seawater and is alkaline brine. The Triassic to Middle-Lower Jurassic coal measures are acidic diagenetic environments, and during their diagenesis The released organic acid makes the interstitial fluid acidic, and the authigenic mineral assemblages formed in both environments are quite different.The diagenetic environment affects the water-rock reaction and secondary pore development to a certain extent