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1.
With the aim of constraining the influence of the surrounding plates on the Late Paleozoic–Mesozoic paleogeographic and tectonic evolution of the southern North China Craton (NCC), we undertook new U–Pb and Hf isotope data for detrital zircons obtained from ten samples of upper Paleozoic to Mesozoic sediments in the Luoyang Basin and Dengfeng area. Samples of upper Paleozoic to Mesozoic strata were obtained from the Taiyuan, Xiashihezi, Shangshihezi, Shiqianfeng, Ermaying, Shangyoufangzhuang, Upper Jurassic unnamed, and Lower Cretaceous unnamed formations (from oldest to youngest). On the basis of the youngest zircon ages, combined with the age-diagnostic fossils, and volcanic interlayer, we propose that the Taiyuan Formation (youngest zircon age of 439 Ma) formed during the Late Carboniferous and Early Permian, the Xiashihezi Formation (276 Ma) during the Early Permian, the Shangshihezi (376 Ma) and Shiqianfeng (279 Ma) formations during the Middle–Late Permian, the Ermaying Group (232 Ma) and Shangyoufangzhuang Formation (230 and 210 Ma) during the Late Triassic, the Jurassic unnamed formation (154 Ma) during the Late Jurassic, and the Cretaceous unnamed formation (158 Ma) during the Early Cretaceous. These results, together with previously published data, indicate that: (1) Upper Carboniferous–Lower Permian sandstones were sourced from the Northern Qinling Orogen (NQO); (2) Lower Permian sandstones were formed mainly from material derived from the Yinshan–Yanshan Orogenic Belt (YYOB) on the northern margin of the NCC with only minor material from the NQO; (3) Middle–Upper Permian sandstones were derived primarily from the NQO, with only a small contribution from the YYOB; (4) Upper Triassic sandstones were sourced mainly from the YYOB and contain only minor amounts of material from the NQO; (5) Upper Jurassic sandstones were derived from material sourced from the NQO; and (6) Lower Cretaceous conglomerate was formed mainly from recycled earlier detritus.The provenance shift in the Upper Carboniferous–Mesozoic sediments within the study area indicates that the YYOB was strongly uplifted twice, first in relation to subduction of the Paleo-Asian Ocean Plate beneath the northern margin of the NCC during the Early Permian, and subsequently in relation to collision between the southern Mongolian Plate and the northern margin of the NCC during the Late Triassic. The three episodes of tectonic uplift of the NQO were probably related to collision between the North and South Qinling terranes, northward subduction of the Mianlue Ocean Plate, and collision between the Yangtze Craton and the southern margin of the NCC during the Late Carboniferous–Early Permian, Middle–Late Permian, and Late Jurassic, respectively. The southern margin of the central NCC was rapidly uplifted and eroded during the Early Cretaceous.  相似文献   

2.
Coal pebbles found in 1994 in the Greham Bell Island (Franz Josef Land Archipelago) are made up of the Barzas-type cuticular liptobiolith. The coal belongs to the initial stage of catagenesis and is characterized by high content of cutinite (up to 70%) with very low reflectance (Ro= 0.1%). Maceration products show some tegillate elements of Arthropodaand individual Devonian spores. It is supposed that plant cuticle and Arthropoda exocuticle are present in this coal. The obtained data suggest the presence of Paleozoic rocks in the sedimentary sequence, although they are not yet recovered. These data complement the available information on the distribution of specific Devonian coals and allow us to have a new insight into the zoogenic material involved in the coal formation.  相似文献   

3.
内蒙古扎赉特旗德发屯地区下三叠统老龙头组的新发现   总被引:3,自引:0,他引:3  
扎赉特旗德发屯地区的木化石原定为PhoroxylonmultiforiumZheng&Zhang,现修订为Scalaroxylonmultiforium(Zheng&Zhang)Zhang&Zhengcomb.nov.,Scalaroxylon迄今仅见于德国南部的晚三叠世沉积中。根据区域地层对比,含木化石的地层是一套红杂色陆相沉积,其地层层序、岩性、岩相特征与邻区的下三叠统老龙头组完全可以进行对比,含木化石的地层层位应为下三叠统老龙头组,而不是“上侏罗统”大磨拐河组。根据这一研究结果,对大兴安岭中部地区的下三叠统老龙头组及哈达陶勒盖组进行了较详细的讨论和对比。  相似文献   

4.
据西藏自治区大地构造演化特征,从整个青藏高原构造单元分布特点考虑,本文将西藏自治区地层区划结合构造单元和含煤地层一并考虑,将其划分为三个构造-地层大区:羌塘-三江构造-地层大区、班公湖-双湖-怒江构造-地层大区、冈底斯-喜马拉雅构造-地层大区。从区域地层、沉积构造及其古生物化石组合等特点综合分析,得出西藏赋煤区聚煤作用具有时代多、分布广、煤层层数多、厚度薄和稳定性差的总体特点。区内含煤地层包括下石炭统、上二叠统、上三叠统、中侏罗统、下白垩统和古近系等。最主要煤系是下石炭统马查拉煤系、上二叠统妥坝煤系、上三叠统土门煤系、下白垩统多尼煤系。  相似文献   

5.
东昆仑地区发育一套显生宙碎屑岩地层,包括下寒武统沙松乌拉组、中—上奥陶统纳赤台群、上石炭统—下二叠统浩特洛哇组、下三叠统洪水川组、中三叠统希里科特组以及上三叠统八宝山组。研究区砂岩的CIA值反映沙松乌拉组砂岩源区化学风化程度较高,其余各组砂岩源区化学风化程度较低。主量和微量元素研究结果表明各组砂岩源区以长英质岩石为主,包含少量中性成分。La、Ce、Th、U、∑REE含量和La/Sc、Th/Sc、Sc/Cr、La/Y比值指示沙松乌拉组和纳赤台群砂岩沉积环境为大陆岛弧或活动大陆边缘,浩特洛哇组砂岩形成于被动大陆边缘环境,洪水川组砂岩沉积环境为活动大陆边缘,希里科特组砂岩的微量元素含量及其比值接近于活动大陆边缘和被动大陆边缘,八宝山组砂岩沉积环境为活动大陆边缘。综合分析认为沙松乌拉组和纳赤台群砂岩形成于原特提斯洋俯冲阶段,浩特洛哇组砂岩形成于古特提斯洋持续扩张阶段,洪水川组砂岩形成于古特提斯洋俯冲阶段,希里科特组砂岩形成于陆(弧)陆初始碰撞阶段,八宝山组砂岩形成于陆陆全面碰撞—碰撞后阶段。  相似文献   

6.
中国南方古生界-中生界油气藏成藏规律及勘探方向   总被引:17,自引:3,他引:17  
中国南方古生界—中生界古油藏主要分布于黔中—雪峰 -江南隆起北侧 (以下古生界及上震旦统灯影组古油藏为主 ,其烃源主要是下寒武统 )及南盘江—十万大山地区上古生界及下三叠统台地及孤立台地边缘 (主要是上古生界及下三叠统自生自储型古油藏 ) ;现存古生界—中生界油气藏主要分布于四川盆地。根据南方多期构造改造及油气演化复杂性的特点 ,将南方古生界—中生界油气藏分成原生、次生及再生烃油气藏 3类。认为南方现存的古生界—中生界原生油气藏很少 ,绝大部分原生油气藏均已破坏成为古油藏 ,四川盆地现存的大多数油气藏是典型的次生油气藏。提出次生气藏有利勘探领域有川东南及大巴山前缘上石炭统—下三叠统、乐山 -龙女寺隆起东南斜坡上震旦统灯影组及下古生界、川西北地区及楚雄盆地北部凹陷上三叠统—下侏罗统煤成气藏 ,再生烃油气藏有利勘探地区有苏北盆地阜宁—盐城—海安—兴化—宝应地区、江汉盆地沉湖地区南部潜江—仙桃—牌州—汊参 1井地区及江西鄱阳盆地南部凹陷。这一认识已经得到苏北盆地盐城凹陷朱家墩气田、川东方斗山背斜带寨沟湾石炭系气田及江汉盆地沉湖地区南部开先台西油藏勘探发现的证实。  相似文献   

7.
We have studied pebbles of igneous rocks from the Lower Jurassic sedimentary succession of Hall Island, Franz Josef Land. Pebbles are represented by felsic intrusive and extrusive rocks, often cataclased and greisenized. The U–Pb age of crystallization for zircons of the studied samples yielded the Latest Devonian–Early Carboniferous and Early–Middle Permian ages. In addition, the studied zircons demonstrate a broad scatter of ages, from Middle Paleozoic to Mesozoic, suggesting repeated thermal reworking and metamorphism of granites. It is shown that coeval Late Paleozoic magmatism indicates the similarity of the geological evolution of the northern Barents Sea and the Severnaya Zemlya archipelago.  相似文献   

8.
试论川渝河包场地区上三叠统须家河组沉积相   总被引:1,自引:0,他引:1       下载免费PDF全文
川渝河包场地区发育上三叠统须家河组,该组假整合于中三叠统雷口坡组海相碳酸盐岩侵蚀面之上,不整合/整合伏于侏罗系红层之下的一套以砂泥岩为主,砂岩与泥岩不等厚互层夹薄煤层的“煤系”地层,该组的沉积相长期存在争议。笔者据野外实测剖面资料,结合室内薄片分析,从沉积学观点系统地分析了其砂体展布、岩性、组构等特征,认为河包场地区的须家河组沉积相为湖泊相,沉积亚相主要为滨浅湖亚相及滨岸沼泽。  相似文献   

9.
我国腐植煤的还原性质及其与沉积环境的关系   总被引:3,自引:2,他引:3  
赵师庆 《沉积学报》1984,2(2):53-65
一、不同还原性腐植煤的基本特征在研究华北聚煤区东部晚古生代太原组(C3)和山西组(P11)煤性质差别及显微特征的基础上,作者认为除煤岩成分和变质程度外,还存在着影响煤质的第三个成因因素--还原性质。  相似文献   

10.
INTRODUCTIONTheLatePaleozoicNorthChinabasinisahugecratonicbasin,thestratadistributionandcoal-bearingcharacteristicsvaryindife...  相似文献   

11.
平顶山煤田的太原组属于混合型的碳酸盐浅海和陆源碎屑海岸沉积。下部和上部灰岩段主要形成于滨海潮间带和浅海中,并在其中发育行风暴浊流沉积。中部碎屑岩段为障壁岛-泻湖-潮坪体系沉积。太原组煤的显微组分为微镜惰煤,煤质属于低灰高硫煤。  相似文献   

12.
南祁连盆地在晚三叠世时期处于陆相沉积,上三叠统阿塔寺组碎屑岩十分发育。盆地三叠系砂岩的岩性及岩相特征与二叠系非常相似,但是源岩构造背景、物质组成及物质来源与二叠系有所差异。根据地球化学主量元素、微量元素分析结果,上三叠统阿塔寺组源岩构造背景活动性较强,以活动性较强的大陆岛弧及活动大陆边缘为主,源岩物质组成以长英质火成岩为主。结合区域地质构造背景判断,南祁连盆地上三叠统阿塔寺组沉积物源区以北物源为主,以南物源为辅,中祁连的前震旦系及下古生界变质结晶岩系及花岗岩为其主要物源。  相似文献   

13.
总结前人研究成果和近期勘探成果,重新确立了该区石炭纪地层层序,将原小海子组解体,以其内部存在的沉积间断为界,其上划为下二叠统南闸组,其下归为上石炭统,并命名为喀拉拜勒组;将原巴楚组解体,其上部“双峰灰岩”段及泥岩段仍为下石炭统巴楚组,下部砂泥岩互层段及砂岩段(东河砂岩段)归入上泥盆统,称东河塘组,并对井下石炭系进行了横向对比。  相似文献   

14.
民和盆地侏罗系地层划分与对比   总被引:2,自引:0,他引:2  
民和盆地是一个油、煤、气伴生的中新生代陆相盆地,侏罗系地层层序自下而上划分为下侏罗统炭洞沟组(大西沟组)、中侏罗统窑街组、红沟组、上侏罗统享堂组。中侏罗世早、中期气候温暖湿润,形成了以沼泽相煤系地层和湖相暗色泥岩、油页岩为主的生油建造,晚侏罗世至白垩纪气候较为干燥,形成了以河流相为主的砂砾岩储集建造。根据古生物、岩性、电性、含煤性、构造、古气候等地层划分对比标志,重新确立了盆地的地层系统,建立了盆地中新生界地层标准剖面,为盆地石油勘探奠定了坚实的基础。  相似文献   

15.
从岩相古地理论中国南方石炭系油气潜景   总被引:8,自引:4,他引:4       下载免费PDF全文
石炭系是中国南方重要的海相含油气地层之一。下石炭统的油气生成条件比上石炭统的好,这和早石炭世的盆地面积较大有关。石炭系下伏的志留系和上覆的二叠系的油气生成条件比石炭系还要好。上石炭统的油气储集条件比下石炭统的好,这和上石炭统的白云岩和滩相石灰岩分布较广有关。石炭系油气藏的直接盖层是下二叠统下部的梁山组,区域盖层是中新生代的泥岩为主的地层。南方石炭系油气生储盖条件的配置关系相当好。但是,南方石炭系以及整个古生代和三叠纪海相地层均经历了多次大的构造变动,其油气藏形成条件遭受相当大的破坏。在有利的生储配置关系的基础上,在区域盖层和保存条件较好的及面积较大的中新生代沉积盆地中,尤其是在邻近石炭系本身或其下伏志留系油气源岩的地区,是寻找和发现石炭系新的油气藏的有利地区。  相似文献   

16.
华北东部地区盆地叠合特征与古生界生烃史   总被引:10,自引:2,他引:8  
胡宗全 《现代地质》2006,20(4):585-591
华北东部地区下古生界沉积了海相碳酸盐岩潜在的烃源岩,上古生界发育良好的煤系气源岩。由于经历了多期次、不同规模盆地的多种样式的叠合,其间又经历多期次的抬升、剥蚀与改造,因此,不同地区的古生界烃源岩生烃史具有显著的差异。地层对比和上古生界RO特征指示研究区北部的济阳坳陷具有较厚的三叠系原始沉积,三叠纪盆地的叠合对古生界烃源岩生烃史具有重要影响。依据盆地叠合方式、上古生界热演化程度,将上古生界生烃史划分为三叠纪、侏罗纪-白垩纪、早第三纪以来等3个阶段,分别对应生烃史的早期、中期和晚期,早期浅埋、中期抬升、晚期深埋型地区的“二次生烃”潜力大,如济阳坳陷和东濮凹陷。上古生界盆地的均衡面式叠合使下古生界的热演化程度比上古生界至少高0.3%以上,因此,在三叠纪末下古生界基本达到生烃高峰,在一定程度上损耗了其原始有机质并降低其“二次生烃”潜力。  相似文献   

17.
塔西南白垩系发育,可分为上、下两统。下白垩统克孜勒苏群可分4段,多以陆相沉积为主,富含棕红色砂砾岩夹少许砂岩、粉砂岩、泥岩和砾岩。上白垩统英吉沙群为海陆相并存,库克拜组可分2段,常见泥岩、膏岩和海相化石;乌依塔格组多为红色泥岩、泥质粉砂岩夹砂岩;依格孜牙组多见灰岩、白云质灰岩,富含海相化石;吐依洛克组为棕红色泥岩、石膏和砂、砾岩,含海相化石。通过勾勒9个岩性单元的沉积相展布,分析昆仑山前白垩纪的沉积环境演化过程。克孜勒苏群西区多为陆相快速堆积,东区远离陆源为三角洲和滨岸沉积,具有宽泛的冲积扇—辫状河三角洲相分布。库克拜组总体显示为辫状河三角洲—潮坪相变的过程;乌依塔格组以潮坪为主;依格孜牙组表现为碳酸盐岩台地—台地边缘的演化;吐依洛克组为宽广潮坪。  相似文献   

18.
The crystallochemical characteristics of Cr-spinels and tourmalines in combination with U–Pb isotope data on detrital zircons from the Upper Permian and Lower Triassic sandstones of the Belskii Depression showed that the main provenances of the molasse sequence in the southern part of the Cis-Uralian foredeep were Lower Paleozoic (Sakmara zone) and Precambrian (Uraltau zone) complexes. The absence of Late Paleozoic zircons in the Tatarian (Upper Permian) sandstones, as well as their small amount in the Lower Triassic psammites together with geochemical and petrographic data, suggest that granite massifs of the Main Granitic Axis of the Urals, as Middle–Upper Paleozoic magmatic complexes of the Magnitogorsk Megazone, were not involved in erosion. At the same time, the significant amount of Precambrian zircons is indicative of the presence of metamorphic complexes in the provenance of the Uraltau zone.  相似文献   

19.
Stable carbon isotopes were used together with molecular markers to constrain genetic relationships between sandstone extracts and potential source rocks in the pre-Tertiary in the Huanghua Depression, North China. Comparison of the extracts from Permo-Carboniferous terrigenous mudstones and Ordovician marine carbonates indicated that their prominent differences are in stable carbon isotopes, molecular markers and thermal maturity. Although the extracts of the Mesozoic and Lower Permian Xiashihezi Formation sandstones have some similar iso-topic characteristics, molecular markers data provide a good correlation between the Upper Jurassic-Lower Cretaceous oils and the Upper Carboniferous Taiyuan Formation mudstones, and between the Lower Permian Xiashihezi Formation oils and the Lower Permian mudstones. The results showed that the Upper Jurassic-Lower Cretaceous sandstone oils were derived chiefly from the Upper Carboniferous Taiyuan Formation terrigenous mudstones and that the Lower Permian Xiashihezi Formation oils were sourced from the Lower Permian Shanxi Formation and Xiashihezi Formation terrigenous mudstones.  相似文献   

20.
为揭示鄂尔多斯盆地多种能源矿产间的关系,根据盆地石油、油气伴生水以及煤、煤层夹矸、铀矿及围岩样品的氯仿沥青中57种元素的分析结果,进行了Q型聚类分析。结果表明:侏罗系下统延安组石油、侏罗系中统直罗组石油与三叠系延长组石油有相近的成因特征;三叠系延长组石油沥青、三叠系延长组含油砂岩沥青与侏罗系中统直罗组石油沥青具有类似的成因特征;神木侏罗系下统延安组煤沥青、东胜侏罗系中统直罗组煤沥青、铜川陈家山侏罗系下统延安组煤层石油以及铜川陈家山侏罗系下统延安组煤沥青成因特征相近;铜川陈家山侏罗系下统延安组煤层石油沥青可能与准格尔黑岱沟石炭二叠系煤沥青具有成因上的联系;侏罗系下统延安组石油沥青与放射性铀矿的形成具有密切关系;天然气的物质来源复杂,且与石油和煤的进一步演化有一定关系。鄂尔多斯盆地多种能源矿产成因较复杂、相互问关系密切,且具有多源性成藏(矿)特征。  相似文献   

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