【作者】 吴海东；

【导师】 胡斌；

【作者基本信息】 河南理工大学 ， 地质资源与地质工程， 2010， 硕士

【摘要】 本论文在总结前人所做工作的基础之上,依据野外露头、测井、岩芯等资料,搜集了平顶山12-20钻孔资料以及其他专著、文献资料,选取禹州大风口、济源下冶两个野外露头作为实测剖面,结合露头、钻井和测试分析资料,综合研究了沉积体系、沉积类型、沉积相、沉积亚相及沉积微相的特征,划分了上、下石盒子组基准面旋回层序,推断基准面升降规律,总结旋回特征,编制上、下石盒子组地层等厚线图、砂地比等厚线图,并绘制出岩相古地理图,在此基础上探讨豫西上、下石盒子组聚煤环境。运用现代沉积学理论,较详细分析了豫西地区上、下石盒子组沉积相、沉积亚相和沉积微相的特征,按沉积亚相划分了沉积类型,建立了十七种沉积类型,包括上三角洲平原8种,下三角洲平原7种,三角洲前缘2种。同时绘制了豫西禹州大风口、平顶山12-20钻孔以及济源下冶地区三地区上、下石盒子组地层柱状图、相柱状图各1幅。将基准面旋回理论应用到豫西上、下石盒子组对该地层进行层序地层划分,分别对平顶山12-20钻孔、禹州大风口和济源下冶三地区的中期、短期基准面层序地层进行划分,识别了平顶山12-20中期基准面旋回8个,均为对称旋回;41个短期旋回,其中对称短期旋回为20个,非对称短期旋回21个,非对称短期旋回以向上变深的退积为主,向上变浅的加积旋回不发育;识别了大风口剖面中期旋回7个,其中对称旋回6个,非对称旋回1个,为向上变浅的半旋回,短期旋回共23个,其中对称旋回为10个,非对称旋回13个,有向上变深和向上变浅的两种非对称旋回;下冶地区识别了4个中期旋回,其中3个为对称旋回,一个为向上变深的非对称旋回,14个短期旋回,其中对称的短期旋回7个,非对称短期旋回7个。并分别探讨了各个地区的中期基准面旋回过程中的短期基准面结构类型的变化和叠置关系。绘制了河南省上、下石盒子组地层等厚线图、砂地比等值线图各1幅,并通过相比法绘制了上、下石盒子组的岩相古地理图。在豫西的中部地区为下三角洲平原,由于分流河道分叉增多且分流间湾发育,只形成一些不稳定薄煤层,仅局部达可采厚度。而在本区南部,三角洲分流间湾变得较开阔,充填淤平后可形成面积较大的分流间沼泽。局部废弃的三角洲朵体上以及广阔的海湾边缘环境也有利于聚煤作用的广泛发育,形成的煤层层数多,厚度大,且较稳定。研究区的聚煤环境主要是分流间湾泥炭沼泽,泥炭坪聚煤环境不发育,随着三角洲不断向前推进,聚煤作用的范围也随之增大。更多还原

【Abstract】 Based on the work done by our predecessors, and relying on the materal of the outcrops, well logging, cores, etc., selecting two outcrops, which are Dafengkou inYuzhou and xiaye in Jiyuan, as the measured profile, collecting data of drilling 12-20 in Pingdingshan, as well as other monographs、references, combining the information of outcrops, drillings and testing analysis, this paper has a comprehensive study on the characteristics of the sedimentary system, deposit types, sedimentary facies, sedimentary subfacies and microfacies, and divides the base-level cyclic sequences in the Upper and Lower Shihezi Formations, infers the lifting rules of base-level, review the cycle characteristics, draws out stratigraphic isopach map and sand-mud ratio contour map of the strata and the lithofacies palaeogeography maps, on this basis the coal-accumulating environment of the upper and lower Shihezi Formations in west Henan has been discussed.With the theory of modern sedimentation, this paper has a detailed analysis on features of sedimentary facies, sedimentary subfacies and microfacies in west Henan, divides the sediment types based on the sedimentary subfacies, including eight types of the upper delta plain, seven kinds of the lower delta plain, three kinds of the delta front. Then the stratigraphic column and formation phase histogram of the Upper and Lower Shihezi Formations in Dafengkou of Yuzhou city, drilling 12-20 of Pingdingshan city, xiaye area of Jiyuan city were drawed respectively.Applied the base-level cycles to the division of sequence stratigraphy of the Upper and Lower Shihezi Formations in western Henan, the medium-term, short-term base-level sequence formation are divided respectively in drilling 12-20 of Pingdingshan, Dafengkou of Yuzhou and xiaye of Jiyuan. 8 medium-term base-level cycles are identified in Pingdingshan 12-20, all symmetrical cycle; 41 short-term cycles, in which 20 symmetrical and 21 asymmetrical, non-symmetrical short-term cycles were mainly retrogradation in order to darken up, any shallowing-upward aggradational cycle was not development; 7 mid-cycles are identified in profile of Dafengkou, in which 6 symmetrical cycles, 1 asymmetric cycle, the half-cycles of upward shallowing, short-term cycles of 23 Among them, 10 symmetrical cycles and 13 non-symmetric cycles, there are two kinds of non-symmetric cycles which includes upward shallowing ones and upward darker ones; 4 medium-term cycles are identified in Xiaye area, in which 3 symmetrical cycles, 1 asymmetric cycle, the half-cycles of upward shallowing, 14 short-term cycles, including seven symmetrical short-term cycles, 7 non-symmetrical short-term cycles.The changement and Superimposition of structural type of the short-term base-level cycles in the process of medium-term base-level in various regions respectivelyhave been Explored.The stratigraphic isopach map, Sand-mud ratio contour map on Upper and Lower Shihezi Formations in Henan Province have been drawn, and lithofacies palaeogeography maps on the strata with facies-comparation method. It was a lower delta plain in the central region of west Henan, due to an increased bifurcation of distributary channel and the development of interdistributary, only some unstable thin coal seams which only can be taken up partially were formed. In the south of this area, the interdistributary became broader, formed larger stream swamp after filling with silt level. Locally abandoned delta body, as well as the edge of the vast bay environment, is also conducive to the extensive development of coal accumulation, the multi-layered coal seams formed are thick, and more stable. It tells that the coal-accumulating environment of the study area should primarily be deltic interdistributary peat bog, peat flat is not developed, with the delta continue to move forward, the scope of coal accumulation is even greater.更多还原