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1.
赣中西部早二叠世晚期—晚二叠世地层   总被引:1,自引:1,他引:0  
曾书明  游玮  覃兆松 《地质通报》2010,29(11):1619-1632
对赣中西部早二叠世晚期-晚二叠世地层进行了多重地层划分,从下至上划分为鸡公岭组、栖霞组、小江边组、茅口组、南港组、乐平组、七宝山组、长兴组;从底至顶划分为Schwagerina cushmani-Darvasites.、Staffella、Misellina claudiae、Parafusulina、Chusenella、Neoschwagerina、Yabeina、Neomisellina、Gallwoayinella、Palaeofusulina minima和P.sinensis11个带,鸡公岭组的Sweetognathus whitei,茅口组Jinogondolella serrata,七宝山组Clarkina leveni、C.guanyuanensis、C.oriantalis,长兴组C.subcarina-ta、C.changxingensis7个牙形石带。同时划分出Shouchangoceras、Anderssonoceras、Prototoceras、Konglingites、Sanyanites5个菊石带。依据生物地层单位将这段地层划分为下统隆林阶,中统罗甸阶、祥播阶、孤峰阶、冷坞阶和上统吴家坪阶、长兴阶。  相似文献   

2.
赣北上二叠统多重地层划分研究   总被引:2,自引:0,他引:2  
覃兆松 《江西地质》2000,14(4):241-250
在开展赣西1∶5万区调中,对上石炭统至下侏罗统开展了岩石地层、层序地层、生物地层、生态地层、年代地层及旋回地层和同位素地层研究,本文即是部分成果的总结。依据岩石特征,将赣北上二叠统分为6个岩石地层区,并创竹亭组代表其深水相沉积。依据七宝山、枣木两剖面资料,进行了生物地层、生态地层及年代地层划分,提出长兴阶顶界位于青龙组底部、底界位于长兴组下部的结论,并对吴家坪阶底界的优选点进行了探讨。通过生态地层  相似文献   

3.
贵州紫云晒瓦晚二叠世深水相地层   总被引:10,自引:1,他引:10  
高勇群  杨逢清  彭元桥 《地层学杂志》2001,25(2):116-119,124
通过对晒瓦晚二叠世岩石地层和生物地层的初步研究 ,认为晒瓦晚二叠世地层属于深水相沉积 ,可划分成4段 ;并根据双壳类、腕足类延限和发育特征 ,分别建立了一个双壳类化石带 (Claraia primitiva- H unanopecten exi-lis组合带 )和二个腕足类化石带 (N eochonetes substrophomenoides- Orthothetina ruber组合带 ,Acosarina dorsisulca-ta- Crurithyris speciosa组合带 ) ;在对牙形石、双壳类和腕足类等典型化石的综合研究基础上 ,首次划分出吴家坪阶和长兴阶 ,改变了以往本区晚二叠世年代地层未细分的状况 ,提高了划分对比精度。  相似文献   

4.
西南地区晚二叠世层序-古地理及聚煤特征   总被引:3,自引:0,他引:3  
西南地区上二叠统赋存有丰富的煤炭资源,含煤地层自下而上分别是峨眉山玄武岩组、龙潭组(宣威组中、下段或吴家坪组)和长兴组(宣威组上段或汪家寨组)。本文对该区晚二叠世含煤岩系层序地层、岩相古地理及聚煤作用进行研究,以区域不整合面、沉积相转换面以及下切谷砂体底部冲刷面等为层序界面,结合石灰岩标志层向古陆方向延伸距离而显示的旋回性特征,将区内含煤岩系划分为3个三级层序和相应的低位、海侵及高位体系域。层序1形成于晚二叠世吴家坪阶早期,主要分布在川南隆起的南北两侧,包括川东北及滇东、黔西地区;层序2形成于吴家坪阶中期,层序3形成于吴家坪阶晚期及长兴阶,层序2和层序3在西南全区均发育。三个层序的发育特征反映出海侵自东向西脉动推进、东深西浅的古地理格局,当时物源区主要为西侧的康滇古陆,沉积相单元有从西到东依次为陆相冲积平原-过渡相潮坪及三角洲-海相碳酸盐台地的沉积相展布规律。成煤环境主要为河流岸后沼泽、三角洲平原分流间湾沼泽、海湾(泻湖)-潮坪沼泽等,以三角洲体系成煤作用最强。总体上随着海水自东向西不断侵进,有利的成煤环境亦随着海平面的上升而不断向西迁移,聚煤中心亦有逐渐向西迁移的规律。  相似文献   

5.
本文应用沉积学和层序地层学的基本原理和方法,采取野外实测与室内微观研究结合,利用区域钻井资料对比层序地层,对贵州平塘地区中上二叠统长兴组的沉积相特征、层序地层特征以及岩相古地理平面展布进行了研究和总结。结果表明,贵州平塘地区上二叠统长兴组发育开阔台地、台地边缘浅滩以及台盆3种沉积环境。长兴组可划分为2个Ⅲ级层序PSQ1和PSQ2,且均由海侵体系域(TST)与高水位体系域(HST)两部分组成,且皆为TST>HST。对比邻区沉积相和层序地层特征,说明纵向上长兴组的沉积环境是由开阔台地、台地边缘浅滩沉积变为深水台盆沉积;横向上自西向东从安顺到甘寨一带在上二叠统层序PSQ2时期,构成了由浅水碳酸盐台地到深水台盆沉积的廊带。且黔南坳陷在晚二叠世,海水总体为由南向北迁徙海侵。  相似文献   

6.
江西中部石炭—二叠系界线   总被引:2,自引:1,他引:2  
<正> 江西中部晚石炭世至早二叠世地层为连续的海相碳酸盐岩沉积,在船山组Sphaero-schwagerina带之上,栖霞组Misellina claudiae带之下有一套深灰色中至厚层生物泥晶灰岩,含(竹蜓)、牙形刺及珊瑚,厚度一般为40—60m。以高安鸡公岭出露良好,故命名鸡公岭组,用以代表江西中部下二叠统最低层位。  相似文献   

7.
运用层序地球化学方法和原理,结合详细的露头层序地层学研究,对西昌盆地下二叠统进行了层序划分和对比。结果表明西昌盆地下二叠统地层可划分为1个二级层序、2个层序组和6个三级层序。P1q层序组(三级层序1、2、3)构成该二级层序的LST和TST,三级层序4下部发育的(茅口组底部)凝缩层相当于二级层序的最大海泛面,而P1m中上部(三级层序4中上部和三级层序5、6)则构成该二级层序的HST。西昌地区下二叠统层序发育形成过程,总体表现为海平面上升和盆地不断向古陆超覆。沉积序列、古氧相含量、锶含量、碳氧同位素和TOC的变化旋回揭示西昌盆地早二叠世经历了6次三级海平面变化旋回(6个三级层序),在华南地区乃至全球范围内均可进行对比。建立的层序充填模式揭示出Hercynian早期全球海平面上升,盆地不断向古陆超覆,奠定了早二叠世西昌海域盆地的轮廓。  相似文献   

8.
中国上石炭统上部及下二叠统海相地层中阶的划分   总被引:8,自引:0,他引:8       下载免费PDF全文
明确而详细地提出了中国上石炭统上部及下二叠统海相年代地层单位的具体框架。将上石炭统上部划分为消遥阶、下场家河阶;下二叠统划分为上杨家河阶、范家河阶、垭口阶及隆林阶。明确了阶的定义、动物群特征、磁性地层特征及其与相关地层的关系。所划分的阶均能与世界标准年代地层进行详细而有依据的对比。  相似文献   

9.
在广东连县-阳山煤田的二叠纪地层中首次采集到牙形刺化石计11属20种和3个未定种。通过与中国南方相应标准剖面对比,建立了4个组合带;茅口阶Neogondolella serrata-N.postserrata组合带,吴家坪阶中、下部Neogondolella liangshanensis组合带、吴家坪阶上部Neogondolella orientalis组合带,长兴阶Neogondalella changxingensis-N.subcarinada组合带。同时讨论了上统与下统、长兴阶与吴家坪阶、下三叠统与上二叠统的地层界线。  相似文献   

10.
鄂南蒲圻、通山、崇阳等地晚二叠世地层发育,含(竹蜓)类化石9个属40个种,其中新种8个,未定种7个,根据它们的地层分布位置,可分两个带、两个亚带,即吴家坪阶Codonofusiella带,长兴阶Palaeofusulina带;后者,下部为Palaeofusulina-Reichelina亚带,上部为Nankinella-Staffella亚带。Codonofusiella及Palaeofusulina混生现象只限于长兴组下部。代表区内长兴阶最高层位不是palaeofusulina,而是新建立的Nankinella-Staffella组合化石亚带。笔者认为,我国南部各地域内都以Palaeofusulina来确定二叠系和三叠系的界线是困难的。   相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
15.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

16.
正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)  相似文献   

17.
正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,  相似文献   

18.
正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)  相似文献   

19.
正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-  相似文献   

20.
正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with  相似文献   

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