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91.
刘海利 《中国煤田地质》2007,19(1):17-18,32
研究区位于山西沁水煤田东南部,晋城矿区的东部边缘,面积96km^2.该区普遍发育石炭、二叠纪地层。区内有晋城煤业集团古书院、王台铺、凤凰山三对生产矿井。以勘探资料为基础,对该区9号煤层赋存规律、成煤古地理及其演化进行了分析研究,阐述了沉积环境对煤层厚度的控制作用。  相似文献   
92.
江汉盆地潜江凹陷东南部储层特征研究   总被引:1,自引:0,他引:1  
研究了江汉盆地潜江凹陷东南部地区构造演化、沉积体系类型及其沉积相模式、沉积体系展布及其控制因素,分析认为潜江凹陷东南部地区新沟嘴组下段主要发育三角洲-咸水湖泊沉积体系,新沟嘴组下段沉积之前发育的深大断裂、继承性古隆起对新沟嘴组下段沉积相展布具有明显的控制作用。沉积微相包括水下分流河道、河口沙坝、席状砂、滨浅湖滩沙、沙坝等多种微相。物源供给和砂体展布都有两支,分别是汉水水系和汉川水系。由于对储层展布认识不清,致使油气的进一步勘探受到了制约。因此,开展沉积相控制下的储层展布特征研究,对该区油气勘探具有重要的意义。  相似文献   
93.
A particular non-stromatolitic carbonate succession making up the third member of the Mesoproterozoic Gaoyuzhuang (高于庄) Formation might demonstrate that a stromatolite decline of the Mesoproterozoic occurring at ca. 1 450 Ma besides other three events of the Proterozoic,respectively,occurred at ca. 2 000 Ma,ca. 1 000 Ma,and ca. 675 Ma. The forming duration of this non-stromatolitic carbonate succession can be generally correlative to that of a similar depositional succession in North America,i.e. a non-stromatolitic carbonate succession made up by the Helena Formation of the Belt Supergroup,which suggests that the stromatolite decline occurring at ca. 1 450 Ma may be a global event. This information endows the non-stromatolitic carbonate succession making up the third member of the Gaoyuzhuang Formation in the Yanshan (燕山) area with important significance for the further understanding of Precambrian sedimentology. The Mesoproterozoic Gaoyuzhuang Formation in Yanshan area is a set of more than 1 000 m thick carbonate strata that can be divided into four members (or subformations). The first member (or the Guandi (官地) subformation) is marked by a set of stromatolitic dolomites overlying a set of transgressive sandstones; the second member (or the Sangshu'an (桑树鞍) subformation) is a set of manganese dolomites with a few stromatolites; the third member (or the Zhangjiayu (张家峪) subformation) is chiefly made up of leiolite and laminite limestones and is characterized by the development of molar-tooth structures in leiolite limestone; the fourth member (or the Huanxiusi (环秀寺) subformation) is composed of a set of dolomites of stromatolitic reefs or lithoherms. Sequence-stratigraphic divisions at two sections,i.e. the Jixian (蓟县) Section in Tianjin (天津) and the Qiangou (千沟) Section of Yanqing (延庆) County in Beijing (北京),demonstrate that a particularly non-stromatolitic succession making up the third member of the Mesoproterozoic Gaoyuzhuang Formation is developed in the Yanshan area of North China,in which lots of grotesque matground structures (wrinkle structures and palimpsest ripples) are developed in beds of leiolite limestone at the Qiangou Section and lots of molar-tooth structures are developed in beds of leiolite limestone at the Jixian Section. The time scale of the Gaoyuzhuang Formation is deduced as 200 Ma (from 1 600 Ma to 1 400 Ma). The duration of an obvious hiatus between the Gaoyuzhuang Formation and the underlying Dahongyu (大红峪) Formation is deduced as 50 Ma to 100 Ma,thus the forming duration of the GaoyuzhuangFormation is thought as 100 Ma (1 500 Ma to 1 400 Ma). Furthermore,the age of the subface of the third member of the Gaoyuzhuang Formation that is just in the mid position of the Gaoyuzhuang Formation can be deduced as about 1 450 Ma,which is the basis to infer a stromatolite decline of the Mesoproterozoic occurring at ca. 1 450 Ma. Importantly,several features of both the molar-tooth structure and the stromatolite,such as the particular forming environment,the important facies-indicative meaning,and the episodic distribution in the earth history,might express the evolutionary periodicity of the surface environment of the earth and can provide meaningful clues for the understanding of the Precambrian world,although their origin and forming mechanism is highly contentious. Therefore,like other three stromatolitic declines,respectively,occurring at ca. 675 Ma,ca. 1 000 Ma,and ca. 2 000 Ma,the identification of the stromatolite decline occurring at ca. 1 450 Ma during the Golden Age of stromatolites (2 800 Ma to 1 000 Ma) has important meaning for the further understanding of the evolving carbonate world of the Precambrian.  相似文献   
94.
重庆市沥鼻峡背斜盐井矿区龙潭组沉积特征及聚煤规律   总被引:1,自引:0,他引:1  
通过对重庆市沥鼻峡背斜盐计矿区含煤地层研究,探讨了矿区龙潭组的沉积特征和聚煤规律,得出矿区龙潭组为泻湖-海湾-潮坪沉积体系,成煤时期的不同沉积环境,聚煤沉降幅度小,沉积速度和物质补偿均衡,有利于泥炭堆积,因此矿区含煤层数、煤层厚度较稳定,该区处于华蓥山潮坪地带,是龙潭期聚煤中心之一。  相似文献   
95.
On the southwestern margin of the Yangtze Block, the Dongchuan Group consists of slightly metamorphosed sedimentary rocks, including silty slate, argillaceous slate, clayey slate, arkose, dolomite, and minor volcanic rocks. To date, it is still a controversy over the depositional age and stratigraphic sequence of the Dongchuan Group. In this study, we analyzed five samples of meta-sedimentary rocks and one sample of meta-tuff from the Yinmin, Luoxue and Etouchang Formations of the Dongchuan Group in the Yuxi region for detrital zircon U-Pb ages and Lu-Hf isotope. The detrital zircon ages of the meta-sediments vary from 3073 to 1703 Ma, mainly clustered at three periods, from 1889 to 1840, 2490 to 2008 and 2878 to 2844 Ma. The youngest age peak of all the samples is ~1859 Ma, with the εHf(t) values of the zircons ranging from-20.3 to +4.3 and more than 90% being negative, indicating that the Paleoproterozoic crustal accretion on the southwestern margin of the Yangtze Block was dominated by reworking of the ancient crustal materials involved in the assembly and breakup of the Columbia supercontinent. Another important age range is between 2490 Ma and 2008 Ma, with εHf(t) values from-14.7 to +8.9 and 70% of them are negative, suggesting that the magmatism in the source area was also dominated by reworking and recycling of the ancient crustal materials, with minor juvenile mantle substances added. The detritus was probably derived from the Paleoproterozoic crystalline basement in the southern Yuxi region. The oldest peak age is ~2847 Ma and the εHf(t) values are from-7.7 to +7.0 with 50% of both positive and negative values, demonstrating a possible ~2.85 Ga ancient continental nucleus on the southwestern margin of the Yangtze Block and substantial growth in juvenile crust materials during this period. Besides, the weighted average age of the zircons from the meta-tuff of the Etouchang Formation is 1677 ± 14 Ma. Combining the previous research data and this study, we can constrain the depositional age of the Dongchuan Group in central Yunnan Province to the period from the late Paleoproterozoic to early Mesoproterozoic, slightly earlier than that of the Dongchuan Group in the Dongchuan area near to the southwestern Sichuan Province. The depositional age of the Dongchuan Group is older than that of the Kunyang Group.  相似文献   
96.
扇三角洲沉积体系及其与油气聚集关系   总被引:23,自引:2,他引:21  
扇三角洲沉积体系是断陷盆地中极为发育的一种沉积体系,主要由扇三角洲平原组合、扇三角洲前缘组合和前三角洲沉积构成,可识别出9种成因相。受沉积物供给速率、可容空间增长速率及盆缘断裂产状等因素控制可划分出退积型、加积型、前积型、陡坡型和缓坡型5种扇三角洲类型。位于扇三角洲平原的辫状分流河道砂体及其位于扇三角洲前缘的与之有成因联系的水下分流河口坝、洪水型重力流砂体等物性好,可以构成优质储层。含油性勘探成果亦证实各主力油层段平面上主要分布于扇三角洲前缘及分流间湾区,小部分位于扇三角洲平原区。受埋藏深度和成岩场的影响,不同地区、不同层位主力油层段的物性与岩性相关性各异。因此,应用沉积体系分布与油气聚集规律挖掘剩余油层及进行远景区预测是有效的与可行的。  相似文献   
97.
本文运用层序地层学理论和工作方法,对吐鲁番-哈密盆地南缘诛罗系地层进行了详细研究,识别出3个I类层序,分别与岩石地层单位八道湾组、三工河组、西山窑组大致相当;在层序体系域、沉积体系研究的基础上,指出层序内高水位体系域(HST)中的辫状河三角洲体系是层间氧化带砂岩型铀矿产出的有利层位。  相似文献   
98.
西北侏罗纪盆地沉积层序演化与储层特征   总被引:9,自引:3,他引:6  
吴因业  罗平 《地质论评》1998,44(1):90-99
笔者研究了西北侏罗纪盆地沉积层序及储层特征,根据露头观察,井下实钻资料及实验室内分析结果,提出中,下侏罗统主要为湖沼相含煤碎屑岩沉积,主要发育河流中冲积相及三角洲相的砂岩集集体,上统为红色或杂色碎屑岩,侏罗纪计导氏孔低渗为主的富含火山岩屑的碎屑岩,局部可发育较好砂岩储层,侏罗系本身可构成妨好的生储盖组合。  相似文献   
99.
南京汤山膨润土矿地质特征,物化性质及矿床成因   总被引:3,自引:0,他引:3  
通过对南京近郊汤山膨润土矿床的矿区地质、矿床地质特征的分析,阐明了该矿床的成因及其矿石的物化性能。综合研究表明,该矿床是以流纹岩及凝灰岩为成矿原岩,在特定的条件下,经热液蚀变改造而形成的矿床。此矿床之矿石属钙基膨润土,经适当选矿后可用于深加工。  相似文献   
100.
赵省民  陈登超  邓坚 《地质学报》2010,84(8):1183-1194
长期以来,由于埋藏深、地质复杂及自然条件恶劣等原因,银根-额济纳旗及邻区石炭系-二叠系的油气勘查程度低,相关研究成果少.鉴于此,本文充分利用研究区的周缘露头,借助近30条剖面的详细调查,分析了本区石炭系-二叠系的沉积特征.研究表明,本区石炭系-二叠系包括了泥岩、砂岩、砂砾岩、碳酸盐岩和火山岩(或火山碎屑岩)等,海相生物丰富.暗色泥岩是石炭系-二叠系的主体,是潜在的烃源岩和盖层;火山岩(或火山碎屑岩)发育,碳酸盐岩多呈透镜状且硅化普遍,砂砾岩相对较少,三者构成石炭系-二叠系重要储层.岩石组成及展布特征表明,石炭纪-二叠纪期间,本区张裂频繁,火山作用强烈,远离陆源区,水体深而宁静,利于生烃物质发育.期间,区内主要发育了浅海相、广海海岸相、碳酸盐台地相、辫状三角洲相、扇三角洲相和火山喷发相等沉积类型.其中,浅海相和局限海岸相主要形成了烃源岩和盖层,其他沉积则形成了储层,为区内石炭系-二叠系造就了良好的油气地质条件.  相似文献   
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