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1.
With abundant deep-water upper Permian sediments,Guizhou is an ideal place for the re-search of radiolarian biostratigraphy of Upper Permian.The sections of Sidazhai and Lekang in southern Guizhou Province are studied.Lithology and biostratigraphy of the siliceous rock sequence of uppermost Permian in the two sections are introduced.Radiolarian assemblage zones,Neoalbaillella optima assem-blage zone and Klaengspongus spinosus assemblage zone in ascending order are established for the top-most Permian of southern Guizhou.The Klaengspongus spinosus zone has been the topmost radiolarian assemblage zone of Permian,which is also correlated with former ones in a considerable depth.  相似文献   

2.
华南造山带下寒武统和中奥陶统发现放射虫   总被引:1,自引:1,他引:1       下载免费PDF全文
在华南造山带江西萍乡下寒武统牛角河组泥质板岩和湖南永州中奥陶统烟溪组硅质岩中首次发现放射虫。放射虫的发现表明萍乡—永州一带寒武纪—中奥陶世存在相当规模的处于低纬度的海盆。  相似文献   

3.
华南地区二叠纪栖霞组碳酸盐岩成因研究及其地质意义   总被引:20,自引:3,他引:17  
颜佳新 《沉积学报》2004,22(4):579-587
二叠系栖霞组是华南地区一个特殊的碳酸盐岩地层,富含有机质和燧石结核,具广泛的空间分布,但是岩相和厚度变化极小,同时发育天青石结核和海泡石。概述前人对这些沉积特殊性的研究成果及存在问题。对其特殊性的深入成因分析表明,栖霞组其他沉积特殊性均与栖霞期的缺氧沉积环境有关,而缺氧沉积环境的成因可能与栖霞期较高的生物产率有关。根据栖霞期全球古气候、古海洋背景研究的最新进展,结合栖霞组的沉积学特征,认为栖霞组特殊性的成因可能与当时较高生物产率有关,进一步研究、确定栖霞期较高生物产率的成因及其变化将具有重要的地质意义。  相似文献   

4.
本文系统论述了西南三江地区那邦、高黎贡山、崇山-澜沧江、点苍山-哀牢山-红河剪切走滑带、区域性伸展与变质核杂岩、新生代盆地及走滑过程中的碱性岩浆活动等特征,认为西南三江地区经历了挤压收缩变形(60~40Ma)、走滑伸展热隆(40~38Ma)、走滑剪切深熔(38~23Ma)、走滑剪切伸展(23~11Ma)、走滑剥蚀隆升(11~5Ma)5个时空演化阶段,并对应5种运动机制及动力学机制:碰撞挤压、走滑拉张热隆(岩浆)、走滑剪切深熔、剪切伸展、走滑垮塌,主要表现为走滑造山。西南三江造山带是印度板块向欧亚板块斜向俯冲形成的多条巨型顺时针走滑剪切带,其间的块体向南逸出并顺时针旋转。走滑断层系起了位移量调节和构造变换的作用,西南三江造山带为典型的走滑造山带。  相似文献   

5.
中国北方地区二叠纪岩相古地理   总被引:7,自引:1,他引:7  
主要以实地踏勘和测量建立的87个标准剖面及529个辅助剖面为基础,通过对二叠系分布格局、岩石学特征、沉积构造特征、古气候、古生态、古环境等分析,来恢复中国北方地区二叠纪的古地理面貌。早二叠世:主要存在额尔古纳和佳木斯古陆,塔里木-敦煌-祁连-内蒙古古陆;海域主要分布在松辽海相区,华北残留海湾相区,柴西残留海湾相区和南准噶尔-吐哈-北山残留海湾相区;此外还有塔里木西部碳酸盐台地相区和准噶尔腹部河湖相区。中二叠世:早二叠世的古陆依然存在,但华北北部古陆范围明显缩小,而准噶尔南缘-吐哈地区已上升成为陆地;海域只局限在东北和南祁连地区,华北地区-北祁连地区大面积为河湖相发育区;塔里木盆地主要为陆相碎屑岩沉积;准噶尔地区发育河湖相沉积,北山残留海盆火山碎屑岩发育。晚二叠世:仅在南祁连地区有海相沉积,其他地区均为陆相沉积,东北地区陆相和湖泊相沉积占主导地位;华北地区-北祁连地区主体为河湖相沉积;塔里木盆地整体为河湖相沉积;准噶尔-吐哈盆地主体为河湖相沉积。  相似文献   

6.
在层序地层研究成果基础上,以沉积体系域和相关界面为编图单元,采用体系域压缩法和瞬时编图法,编制了西南地区二叠纪层序古地理图,全面系统地阐述了该区二叠纪层序古地理演化特征。与传统的岩相古地理图相比,层序古地理图具有动态、精确、等时和实用等优点。  相似文献   

7.
中国西南地区煤中砷的含量与对比   总被引:4,自引:0,他引:4  
总结了中国西南云、贵、川、渝三省一市各主要含煤时代的主要煤层和各煤类煤中砷含量及其分布特征,并与国内外的资料进行了对比。通过分析,认为西南各省中以云南省砷含量最高,各成煤时代以寒武纪老地层中的石煤含量最高,而各煤种中以石煤和褐煤砷含量最高。  相似文献   

8.
中国南方二叠纪层序地层时空格架及充填特征   总被引:9,自引:0,他引:9  
李祥辉  王成善 《沉积学报》1999,17(4):521-527
据华南二叠纪不同沉积盆地层序地层区域分布、纵向演化及其充填特征分析研究,初步建立了上扬子克拉通-右江盆地-钦防盆地、中扬子克拉通及全区的层序地层时空格架模型;提出层序充填可分为两个阶段:早二叠世碳酸盐缓坡-台地层序充填阶段,晚二叠世陆源碎屑为主与火山碎屑相混层序充填阶段;认为全区二叠纪四个Ⅰ型层序受控于构造隆升事件,晚二叠世层序TST普遍发育火山碎屑沉积,古陆边缘HST或少量SMT/LST大多由三角洲沉积体系进积叠加而成,上扬子克拉通及右江地区的生物礁以海侵和高位型为特色。  相似文献   

9.
中国南方二叠纪层序地层划分与对比   总被引:21,自引:5,他引:21  
王成善  寿建峰 《沉积学报》1999,17(4):499-508
对中国南方二叠纪时期不同沉积盆地类型的沉积层序进行了深入研究,综合各种盆地类型的沉积层序,该期可识别11个层序单元(S1~S11),其中,栖霞、茅口、吴家坪三阶分别含三个层序,长兴阶两个层序,S1、S6、S7、S11为Ⅰ型,其余为Ⅱ型。层序对比显示,上、中、下扬子的层序数量相近,界面特征各不一致,靠近古陆处在P/C、P1/P2界线间缺少层序1~2、3~5个不等;华南太平洋构造域影响区层序体系域具HST>TST结构,特提斯域控制区则具HST  相似文献   

10.
A new macrofossil Lagerstatte was discovered from the uppermost Ediacaran Jiucheng Member at Jinning and Jiangchuan of the eastern Yunnan, yielding numerous diverse well-preserved thallophyte macrofossils. These include the previously-known representatives of vendobionts, Vendotaenia and Tyrasotaenia, and the biggish multicellular benthos such as Otuaria-like and Tawuia-like fossils, as well as Longfengshaniaceaens with diverse holdfast structures. There are still some other problematic macrofossils with peculiar configurations as well as uncertain relatives. The distinct dominance of the giant, unbranching thallophytes occasionally with holdfast structures distinguishes this assemblage from the other Ediacaran macrofossil Lagerstattes in the Doushantuo Formation at Miaohe, Wenghui and Lantian, and the contemporary assemblage in the Shibantan Member of Dengying Formation, Yangtze Gorges area. This paper outlines the characteristics of some of the multicellular macrofossils from the Jiucheng Member at Jiangchuan. They include some macrofossils with different types of holdfast structure, larger Chuaria-like and Tawuia-like morphology and questionable affinities as well. The discovery of greater diverse macrofossil assemblages from the Jiucheng Member of eastern Yunnan has further indicated that an important diversification and evolutionary radiation of metaphytes took place in the latest Ediacaran time. This radiation of large-scale, benthic metaphyte along with phytoplankton was likely important contributors to the early Cambrian explosion of metazoans.  相似文献   

11.
华南地区晚二叠世煤的稀土元素特征   总被引:3,自引:0,他引:3  
在华南地区贵州六盘水、江西乐平和湖北黄石矿区以及重庆钟梁山和磨心坡煤矿晚二叠世煤的稀土元素电感耦合等离子质谱分析数据的基础上,系统研究了华南地区煤的稀土元素的质量分数分布特征、赋存特征、配分模式及其地质控制因素.煤的稀土元素质量分数与灰分质量分数呈正相关关系,部分煤样品由于有富稀土元素的重矿物组合的存在而出现稀土元素的异常高值.同一矿区晚二叠世煤的稀土元素配分模式具有一定的相似性,而不同地区晚二叠世煤的稀土元素配分模式则差异较大.煤的沉积环境、煤中无机矿物的组成以及海水的影响是控制煤的稀土元素质量分数及其配分模式的主要地质因素.  相似文献   

12.
INTRODUCTIONMining activlties have significant envi ronmenta1 inll)ac'l ssuch as visual intrusions, dust, noise, blasting, trafflc and h}'drology (Kwolek, l999; Ripley et al., l996 ). The l)rot'csst'sof mineral extraction, processing, smelting and refinlng;1rt'never approximate to the environmental neutrality, but tht' affected areas can be ameliorated (KwoIek, l999; Klukanov;1;llltlRapant, 1999). The regions, where mining activities are I,r('sent or continuous for a long tlme, are pote…  相似文献   

13.
通过实测地层剖面的精细研究,结合微量元素地球化学分析,探讨了恩施地区富硒地层中二叠世孤峰组层序界面识别、层序划分与对比及其对硒元素空间分布的影响。研究区中二叠世孤峰组可总结为4种基本层序类型,分别为炭硅质页岩-炭硅质岩、炭硅质页岩-炭硅质岩夹灰岩透镜体、炭硅质岩-含炭泥晶灰岩和炭硅质岩-含炭细晶白云岩;识别出3个层序界面,其中孤峰组与茅口组接触界线处为Ⅲ型层序界面,孤峰组中部的岩性结构转换面为Ⅱ型层序界面,龙潭组与孤峰组接触界线处为Ⅰ型层序界面;划分了2个三级层序(SQ1、SQ2)。通过层序对比分析,随着海侵作用的持续发展,区域上层序内部结构及基本层序类型分异明显,沉积古地理格局表现为南浅北深的特征;通过层序地层与硒异常耦合关系分析,发现了孤峰组内部Ⅱ型层序界面附近具高硒异常特征,确立了新的找矿标志。  相似文献   

14.
A new macrofossil Lagerstatte was discovered from the uppermost Ediacaran Jiucheng Member at Jinning and Jiangchuan of the eastern Yunnan, yielding numerous diverse well-preserved thallophyte macrofossils. These include the previously-known representatives of vendobionts, Vendotaenia and Tyrasotaenia, and the biggish multicellular benthos such as Chuaria-like and Tawuia- like fossiis, as well as Longfengshaniaceaens with diverse holdfast structures. There are still some other problematic macrofossils with peculiar configurations as well as uncertain relatives. The distinct dominance of the giant, unbranching thallophytes occasionally with holdfast structures distinguishes this assemblage from the other Ediacaran macrofossil Lagerstattes in the Doushantuo Formation at Miaohe, Wenghui and Lantian, and the contemporary assemblage in the Shibantan Member of Dengying Formation, Yangtze Gorges area. This paper outlines the characteristics of some of the multicellular macrofossils from the Jiucheng Member at Jiangchuan. They include some macrofossils with different types of holdfast structure, larger Chuaria-like and Tawuia-like morphology and questionable affinities as well. The discovery of greater diverse macrofossil assemblages from the Jiucheng Member of eastern Yunnan has further indicated that an important diversification and evolutionary radiation of metaphytes took place in the latest Ediacaran time. This radiation of largescale, benthic metaphyte along with phytoplankton was likely important contributors to the early Cambrian explosion of metazoans.  相似文献   

15.
Chroniosuchians are basal tetrapods owing to Anthracosauromorpha and the oldest species of chroniosuchians have been recorded in the Late Permian of Russia so far. In this study, we present evidence for their existence in the Middle Permian of China, based on well preserved diagnostic vertebrae with associated osteoderms from the Dashankou fanua in northwestern China. The finds clearly show interosteoderm articulation pattern between the adjacent scutes in bystrowianids. The features observed in Yumenerpeton yangi may warrant the close proximity or phyletic succession of the chroniosuchid and bystrowianid types of the osteoderm design.  相似文献   

16.
中国南方二叠纪海平面变化及升降事件   总被引:15,自引:5,他引:15  
王成善  李祥辉 《沉积学报》1999,17(4):536-541
在对中国南方二叠纪层序地层、充填特征及沉积演化认识基础上,通过研究海平面升降变化及事件后认为:华南二叠纪相对海平面升降旋回与其层序数量一致,升降型式可有两种且互成影像;二级海平面升降包括“二分式”和“单分式”,前者以扬子区为代表,后者典型见于华夏区;海平面升降事件发生在栖霞早期、茅口早期、茅口末期、吴家坪早期及长兴中后期;二级、三级海平面变化在升降样式、数量、相位上与欧美各地有所不同,其成因与所处构造域有关。  相似文献   

17.
广西东攀剖面二叠系顶部粘土矿物特征及古气候意义   总被引:2,自引:1,他引:1  
对广西东攀剖面二叠系顶部20个样品中的粘土矿物进行X射线衍射分析。伊利石结晶度值显示这些样品形成于中晚成岩带的地质环境;伊利石、蒙脱石纵向分布规律和伊利石结晶度与伊利石含量的关系表明伊利石除陆源碎屑来源外,可能有部分为蒙脱石伊利石化而成;伊利石结晶度变化曲线和伊蒙混层类型的变化规律表明,本区粘土矿物组合与含量的变化除受到后期成岩作用的影响外,还明显地受沉积因素的控制;伊利石结晶度、伊利石化学指数、高岭石和伊利石的含量、伊蒙混层类型显示东攀剖面以9、10层界线上方5cm为界,古气候由干冷变为湿暖;水介质由偏碱性向酸性转变。  相似文献   

18.
中国二叠纪年代地层划分和对比   总被引:51,自引:3,他引:51  
王向东 《地质学报》1999,73(2):99-108
自从采用多重地层分类原则后,我国地层学者提出了许多新的二叠纪年代地层单位。本文论述了经过筛选和重新厘订的中国二叠纪年代地层系统。中国二叠系被划分为3个统8个阶。其中,船山统包括紫松阶和隆林阶,阳新统又分成硒霞亚统及所属的罗甸阶和祥播阶。茅口亚统及所属的孤峰阶和冷坞阶;乐平统包括吴家坪阶和长兴阶。文中还讨论了中国各大地层区二叠纪沉积的年代对比以及中国与国际二叠纪年代地层系统的关系。  相似文献   

19.
Chronostratigraphic Subdivision and Correlation of the Permian in China   总被引:11,自引:0,他引:11  
Since the principle of multiple stratigraphic classification has been widely accepted by Chinese stratigraphers, various new Permian chronostratigraphic units have been proposed in China, and they need to be redefined. The establishment of a new global chronostratigraphic scheme of the Permian, compilation of Permian lithostratigraphic units and updating of Permian biostratigraphic sequences of China makes it possible to present a revised regional chronostratigraphic succession for the Permian System in China. This succession consists of three series and eight stages. The Chuanshanian Series includes two stages, the Zisongian and the Longlinian; the Yanghsinian (Yangxinian) Series is subdivided into the Chihsian (Qixiaan) and the Maokouan Subseries, of which the former comprises the Luodianian and the Xiangboan Stage, and the latter the Kufengian (Gufengian) and the Lengwuan Stage; the Lopingian (Lepingian) Series includes the Wuchiapingian (Wujiapingian) and the Changhsingian (Changxingian) Stage.  相似文献   

20.
1IntroductionThe formation of the Junggar,Turpan and Ili ba-sins is ascribed to Hercynian orogeny between theJunggar and Tianshan Mountains during the MiddlePermian.The rock assemblage of thick and stable sedi-mentary dark muddy shales interbedded with th…  相似文献   

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