准噶尔盆地乌尔禾地区二叠系风城组盐类矿物特征及成因

发布时间：2018-03-04 12:06

本文选题：准噶尔盆地　切入点：乌尔禾　出处：《成都理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：热水沉积一直是各国地质学界的前沿问题和研究热点,国内外针对湖相热水沉积岩的相关研究报道相对较少。乌尔禾地区风城组致密油储层是一套成因非常特殊的湖相“暗色细粒含盐火山-沉积建造”,岩性为富含盐类矿物的深湖相云质岩类,早期的研究认为属较罕见的湖底热液喷流沉积成因。这套深湖沉积建造中发育了大量盐类矿物,如白云石、铁白云石、硅硼钠石、碳酸钠钙石、苏打石、石盐、硬石膏等,引起了作者所在团队的高度关注,但却在前期的研究很少提及。本文充分调研前人对海相/湖相、蒸发/热液成因盐类矿物的研究成果,以沉积学、岩石学、矿物学、储层地质学和地球化学等学科理论为指导,通过钻井岩心观察,薄片鉴定,扫描电镜分析,X衍射分析,电子探针分析,同位素分析,微量元素分析,稀土元素分析,包裹体显微测温和激光拉曼分析等技术手段,围绕着研究区风城组盐类矿物展开深入的研究。通过分析研究区的区域构造背景、沉积环境、岩石学和矿物学特征,得出盐类矿物的特征,并证明研究区风城组的盐类矿物与现代蒸发盐湖沉积的特有盐类矿物不同,凸显出特殊性。分析地球化学特征,得出成矿流体的性质及来源,并证明沉积环境为相对封闭、还原、有间歇性海水混入的深湖环境。在此基础上得出盐类矿物的成因类型,并建立起研究区风城组湖相盐类矿物的内、外源混合成因的深盆热液双扩散对流成盐模式。
[Abstract]:Hot water deposition has always been a frontier problem and research hotspot in the geological circles of various countries. There are relatively few reports on lacustrine hydrothermal sedimentary rocks at home and abroad. The dense oil reservoir of Fengcheng formation in Wuerhe area is a set of very special lacustrine facies "dark fine-grained salt-bearing volcano-sedimentary formation", and its lithology is salt-rich. Deep-lacustrine dolomites of mineralogy, Early studies considered it to be a rare source of hydrothermal jet deposition at the bottom of the lake. In this set of deep lake sedimentary formations, a large number of salt minerals, such as dolomite, iron dolomite, boronite, sodium carbonate, soda, stone salt, anhydrite, etc., were developed. In this paper, the previous researches on marine / lacustrine facies, evaporation / hydrothermal genesis, salt minerals, and sedimentology, petrology, mineralogy, etc. Guided by the theories of reservoir geology and geochemistry, through drilling core observation, thin section identification, scanning electron microscope analysis, electron probe analysis, isotope analysis, trace element analysis, rare earth element analysis, The inclusion microthermometry and laser Raman analysis are used to study the salt minerals of Fengcheng formation in the study area. By analyzing the regional tectonic background, sedimentary environment, petrology and mineralogical characteristics of the study area, The characteristics of salt minerals are obtained, and it is proved that the salt minerals of Fengcheng formation in the study area are different from the special salt minerals of the modern evaporative salt lake deposits. It is proved that the sedimentary environment is a deep lake environment with relatively closed, reduced and intermittent seawater mixing. On this basis, the genetic types of salt minerals are obtained, and the interior of lacustrine salt minerals of Fengcheng formation in the study area is established. A deep basin hydrothermal double diffusion convection salt formation model of mixed exogenous origin.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

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