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1.
新疆晚奥陶世床板珊瑚、日射珊瑚及其生物地层学意义   总被引:1,自引:0,他引:1  
新疆晚奥世床板珊瑚、日射珊瑚化石现已发现44属.152种.本文建立了三个床板珊瑚组合(Catenipora-Eofletcheria组合,Agetolites-Rhabdotetradium组合,Procatenipora-Para-tetradium组合)和二个日射珊瑚组合(Fuyunolites组合,Plasmoporella组合).根据珊瑚的分布规律,推测晚奥陶世新疆存在环准噶尔海和环塔里木海两个海区,并推测现北纬20°—80°为当时热带和亚热带气候区,古赤道位于现北纬50°位置.新疆当时处于赤道以南热带和亚热带范围,致使床板珊瑚、日射珊瑚空前繁盛.  相似文献   

2.
研究区志留纪床板珊瑚、日射珊瑚集中见于中晚志留世 ,其属种繁多 ,数量庞大。根据属群分异特征及发育状况 ,可将其归入古亚洲域 ,并细分为 3个生物省、6个生物亚省。综观志留纪珊瑚的分布 ,推测古亚洲域珊瑚的分布与古纬度关系密切 ,其分布范围为现今北纬 2 0°~ 80°,古赤道位置相当于现今北纬 50°左右 ,由于古构造格局的影响 ,各生物省之间均有地块或深海沟阻隔 ,加上火山活动影响 ,致使各生物省和亚省之间特征各异  相似文献   

3.
<正> 新疆北部阿尔泰山、东、西准噶尔及北天山地区,下、中、上泥盆统皆有床板珊瑚,垂直变化明显,形成了自奥陶纪以来第三个繁盛期。本文将本区泥盆纪床板珊瑚分布规律及其组合特征介绍如下:  相似文献   

4.
林芳 《地质论评》1963,21(1):49-50
床板珊瑚是古生代珊瑚中分布最广泛的类群之一。近三十年来,世界各国对这种化石进行了较详细的研究工作。根据它不仅可以将古生代地层划分到统,甚至可以划分到段或带。它对地层的划分具有重大意义。我国幅员广大。古生代床板珊瑚化石分布极  相似文献   

5.
新疆哈密地区早泥盆世珊瑚动物群及其地质意义   总被引:2,自引:0,他引:2  
张孟  郑飞  南玲玲  张雄华  黄兴  靳锁锁 《地质通报》2018,37(10):1789-1797
新疆哈密地区下泥盆统发育,南部图拉尔根地区下泥盆统为大南湖组,北部三道白杨沟地区为卓木巴斯套组。在大南湖组中共发现四射珊瑚2属5种,床板珊瑚7属12种,并建立四射珊瑚组合Syringaxon moriense和床板珊瑚组合Pseudofavosites giganteus;在卓木巴斯套组共发现四射珊瑚5属7种,床板珊瑚2属2种,并建立四射珊瑚组合Orthopaterophyllum junggarense和床板珊瑚组合Pachyfavosites junggarensis。通过珊瑚在地层中的分布及组合的时代对比,确定前者的时代为早泥盆世埃姆斯期早期,后者的时代为埃姆斯期中晚期。通过与国内外典型的早泥盆世埃姆斯期珊瑚动物群的对比,认为哈密地区的珊瑚动物具有典型的早泥盆世温带动物群特征,在生物古地理区系上属于北方大区准噶尔-兴安省。  相似文献   

6.
何心一  陈建强 《现代地质》1998,12(2):151-159
摘 要  提出扬子区是奥陶纪、志留纪四射珊瑚的起源中心。早古生代扬子区最早出现的四射 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse 提出扬子区是奥陶纪、志留纪四射珊瑚的起源中心。早古生代扬子区最早出现的四射 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse- lasma‚包珊瑚类 Amplexoides‚Synamplexoides‚十字珊瑚类 Eostauria‚Ceriaster‚Stauria 以及 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse lasma‚包珊瑚类 Amplexoides‚Synamplexoides‚十字珊瑚类 Eostauria‚Ceriaster‚Stauria 以及 泡沫珊瑚类 Rhizophyllum 等。它们在扬子区中奥陶世和早志留世地层迅速繁衍‚尔后扩散至 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 泡沫珊瑚类 Rhizophyllum 等。它们在扬子区中奥陶世和早志留世地层迅速繁衍‚尔后扩散至 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 区早志留世(包括 Wenlockian 阶)珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦有紧密联 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 区早志留世(包括 Wenlockian 阶)珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦有紧密联 系。扬子区早志留世珊瑚群与澳大利亚东部、北美东部同期珊瑚也有一定的相似性。 区早志留世(包括 Wenlockian 阶)珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦 系。扬子区早志留世珊瑚群与澳大利亚东部、北美东部同期珊瑚也有一定的相似性。  相似文献   

7.
杨冬红  杨德彬 《世界地质》2010,29(4):652-657
潮汐变化引起的大气圈、海洋圈和岩石圈差异旋转的计算结果显示:地球扁率变大时,赤道面的高速气流和洋流产生与地球自转方向相反的由东向西运动,类似赤道东风带;地球扁率变小时,大气和海洋赤道突起减小并向两极流动,在南北纬35°线以上的中高纬度地区,形成两极突起,该计算结果与全球风带分布完全符合。综合分析表明,太阳在赤道面时,赤道东风加强,海洋南北赤道暖流加强;太阳在南北回归线时,西风带加强。日、地、月在同一直线上时将增强这一效应。日月大潮引起的大气、海洋和固体地球的差异旋转是日食多次发生在赤道引发拉尼娜事件产生的动力学机制。  相似文献   

8.
研究区位于华北板块的东北部 ,晚石炭世为海陆交互相沉积。海相灰岩层中产有大量珊瑚、竹蜓 、腕足类及双壳类化石。共描述皱纹珊瑚 7属 15种 ,其中新种 11个 ,1个未定种。珊瑚化石组合中 ,小型单体珊瑚、中大型单体珊瑚和群体珊瑚共同繁育 ,种属分异度高 ,且地方性种数量大 ,表现为热带 -亚热带生物区系的特点 ,说明华北板块晚石炭世古地理位置应位于古赤道附近的热带 -亚热带 ,为古特提斯洋中的古板块之一  相似文献   

9.
何心一  陈建强 《地学前缘》2006,13(6):145-152
对扬子区中奥陶世至晚志留世四射珊瑚已发表的属种进行全面清理和厘定。现统计扬子区中奥陶世至晚志留世四射珊瑚约有117个属,其中以晚奥陶世和早志留世珊瑚属数最多。117个属中至少有30个属最早出现在扬子区中、晚奥陶世和早志留世地层。因此,扬子区被认为是奥陶纪、志留纪四射珊瑚起源中心之一。完善和修订扬子区中奥陶世至晚志留世四射珊瑚组合序列,使地层时代划分上均与国际通行标准(统、阶)接轨。尤其对扬子区早志留世Rhuddanian晚期,Aeronian早、晚期以及Telychian早、晚期四射珊瑚组合的重新建立和细分。最新资料表明晚奥陶世观音桥四射珊瑚动物群不但有更多的北欧同期的珊瑚分子,而且还产有北美标准属种Salvadorea,Brachyelasmasubregulare等说明两者也存在一定的联系。扬子区早志留世(Llandovery)的众多四射珊瑚属均为世界广布的,但也有许多地方性属(约有22个,占总数的23·4%)。就珊瑚生物古地理关系,它与同期的西伯利亚、哈萨克斯坦和澳大利亚珊瑚群较密切。  相似文献   

10.
东秦岭古生代古生物区与古地理变迁   总被引:2,自引:0,他引:2  
王建平  裴放 《地质论评》2002,48(6):603-611
本文根据对东秦岭古生代各纪古生物区的分析,指出在北美岭褶皱带,二郎坪海槽寒武纪放射虫和微浮游植物属华南区,奥陶纪头足类,腹足类、珊瑚为华北区,早志留世珊瑚为华南区,柿树园海槽中泥盆世至二叠纪孢子主要见于华南区,干江河海槽泥盆纪珊瑚,海百合为华南区。在南秦岭褶皱带,浙川陆棚寒武纪三叶虫有华北区和华南区的分子,奥陶纪牙形石、头足类由华南区变为华北区,晚奥陶世腕足类、三叶虫、珊瑚为华北区,而早志留世笔石,晚泥盆世珊瑚,腕足类和Ting、古植物以及早石炭世珊瑚和Ting均为华南区,南湾海槽泥盆纪孢子为华南区。在此基础上探讨了东秦岭古生代古地理变迁过程。  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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