【作者】 封丽洁；

【导师】 高金汉；

【作者基本信息】 中国地质大学(北京) ， 古生物学与地层学， 2012， 硕士

【摘要】 研究区范围西起甘肃肃南东至宁夏同心，北起甘肃张掖-武威一线，南抵甘肃天祝一靖远一线的广大区域。本文以现代沉积地质学、岩石学、岩相古地理学为理论基础，通过野外剖面测量、沉积相分析并结合前人研究成果，对甘肃河西走廊地区3条实测剖面、26条收集剖面的下石炭统进行沉积相及岩相古地理研究，并取得了以下主要成果：（1）通过野外露头研究及室内岩石薄片鉴定，对河西走廊地区下石炭统主要岩性进行了研究，并将其划分为灰岩、白云岩、砂岩、泥（页）岩、硅质岩、石膏和煤7种类型。其中，以灰岩、砂岩和泥页岩为主，白云岩、石膏、煤及硅质岩往往分布局限或成夹层状产出。（2）根据剖面岩性、沉积构造、含化石组合等，对研究区29条剖面的下石炭统进行了详细的沉积相划分，共识别出4大沉积体系、8种沉积相及若干种沉积微相，并对各沉积相和沉积微相进行了详细分析。4大沉积体系分别为碳酸盐岩台地、浅海体系、障壁-潮坪-泻湖体系和三角洲体系；8种沉积相包括开阔台地相、局限台地相、浅海相、潮坪相、泻湖相、障壁岛相、海湾相和三角洲相。（3）根据剖面相序结构的分析，对研究区4条剖面进行了详细的沉积旋回划分，将其划分为3个沉积旋回。由于各剖面地层发育完整性不同，所以各剖面旋回数目不尽相同。（4）根据29条剖面的横向对比，利用单因素分析多因素综合作图的方法，以阶为单位详细编制了走廊地区早石炭世岩相古地理图。在此基础上，详细总结了各主要沉积相带的区域展布特点及古地理演变规律。更多还原

【Abstract】 The study area is bounded by Sunan to the west of Gansu, Tongxin of Ningxia tothe east, Zhangye and Wuwei area to the north, Tianzhu and Jingyuan area to thesouth. on the basis of theories of Sedimentary geology, petrology, Lithofaciespaleogeography and the investigation of filed sections and analysis of sedimentaryfacies, coupled with previous study, the following fruitfull results have been achieved:The research of main lithology of lower Carboniferous in Hexi Corridor ofGansu prov.ince have been conducted by outcrop observation and thin sliceindentification, and limestone, dolomite, sandstone, mud(shale), cherts, gypsum andcoal are recognized as seven main types, among which limestone, sandstone, mud arethe majority and dolomite, gypsum and coal usually locate in limited area.According to the lithology, sedimentary structure and fossil assemblages， adetailed sedimentary facies division for lower Carboniferous in research area havebeen made and4sedimentary systems and8sedimentary facies and severalSedimentary micro facies have been identified. Four sedimentary systems arecarbonate platform, shallow water system, the barrier-tidal flat-lagoon system anddelta system separately;8sedimentary facies include open platform facies, restrictedplatform, shallow marine, tidal flat, lagoon, barrier Island phase, Gulf and delta faciesUnder the analysis of facies sequence configuration,3sedimentary three-level-cycles have been divided after a detailed division for sedimentary cycle of4sectionsin research area. The number of cycle in different section is not the same because ofthe difference of strata integrity.According to horizontal contrast of29sections, an Early Carboniferouslithofacies paleogeography map of Hexi Corridor in unit of stage have beenelaborated by mapping method of univariate analysis and multifactor comprehensive.A detailed conclusion about distribution characteristic of major sedimentary faciesand palaeogeographic evolution are made.更多还原