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1.
Traumatocrinus hsui Mu, 1949是关岭生物群的重要组成成员,以数量众多、保存精美、营假浮游生活闻名于世。笔者等通过对5件群体保存标本中的127个大小不同个体的系统描述和形态定量分析,认为T. hsui萼部与整个冠部存在异速生长的特征,个体发育过程中腕的级数和数目逐渐增加;T. hsui的个体发育可分为3个时期6个阶段,即幼年期(Ⅰ、Ⅱ)、少年期(Ⅰ、Ⅱ、Ⅲ)、成年期;幼年期:个体较小,冠高小于26 mm,腕分枝至4级;少年期:个体中等,冠高26~130 mm,腕分枝至7级;成年期:个体较大,冠高大于130 mm,腕分枝至8级。前人在关岭生物群中研究命名的Traumatocrinus hsui enormis Mu, 1949,Traumatocrinus kueichouensis Mu, 1949,Traumatocrinus uniformis Mu, 1949,Traumatocrinus sp. Mu, 1949,Traumatocrinus guanlingensis Yu et al., 2000和Traumatocrinus xinpuensis Wang et al., 2002等均为T. hsui的同种异名,其命名标本为个体发育的不同阶段或局部特征。  相似文献   

2.
贵州关岭创孔海百合新材料的发现   总被引:1,自引:0,他引:1       下载免费PDF全文
通过对采自贵州关岭地区三叠系小凹组的2块海百合化石标本的研究,认为该标本与以前发现于该地区相同层位的Traumatocrinus hsui Mu在冠部和茎部结构特征均有较大差异,并据此建立新种Traumatocrinus strumiformis sp.nov.。  相似文献   

3.
最近,在关岭、兴义一带上三叠统竹杆坡组中发现了海百合化石群。海百合产于上三叠统竹杆坡组底部1.5m的泥质灰岩层面上,海百合保存非常完好,常以丛状群体出现,根、茎、萼完整。丛状海百合群体由3~42枝海百合组成,海百合与双壳类:Daonella、菊石:Protrachyceras共生,亦见少量的水生爬行动物贵州龙与其共生。最近王立亭在竹杆坡组中发现晚三叠世牙形刺分于Neogondolella polygnathiformic,N.naantungensis,N.Tad pola将其归入晚三叠世。 海百合化石群主要分子有:Traumatocrinus hsui Mu,Traumatocrinus hsui enormis Mu,Encrinus liliformis Miller,占海百合化石群的90%。Traumatocrinus冠大,上宽下窄,萼部呈腕状,有5个内底板,5个底板,5个辐板,10个腕板及一个间腕板,三级腕20个,双列,内侧分,具有羽枝,在分枝处生长出疣和刺。茎圆,茎的中孔圆而小,节面上有放射状的小沟通到茎的缝合线处,形成许多小孔,节面小沟间的脊顶由许多人字形的突起排列而成。茎板近萼部分3、4级,向根渐渐变成各节近等,并变薄。该化石群为丛状群体.由3~42枝海百合组成、茎最粗者达2.2cm,小者为0.3cm,茎最长达1.4m,小者0.1m,经对完好海百合统计,茎节(茎板)一般为376节。茎中部的茎节×茎径=5.85。冠最大者达38cm,具五级羽枝,一  相似文献   

4.
关岭生物群——世界上罕见的化石库   总被引:9,自引:3,他引:9       下载免费PDF全文
以产保存完美海生爬行动物和海百合化石为特色,多门类脊柱动物、无脊柱动物共同繁盛,且夹带有少许古植物化石的关岭生物群是世界上极为罕见的珍衡古生物组合。其化石保存之完美,类型之多样,数量之丰富,堪称世界上少有的晚三叠世“化石库”。在该“化石库”中,海生爬行动物主要有鱼龙类(ichthyosaurs):Qianichthyosaurus zhoui Li(1999),Cymbospondylus asiaticus Li et You(2002),Panjiangsaurus epicharis Chen et Cheng gen.et sp.nov.;海龙类(thalat-tosaurs):Anshunsaurus huangguoshuensis(Liu,1999),Xinpusaurus suni(Yin et al.,2000),X.banaolinensis Cheng et Liu sp.nov.Shun齿龙类(placodonts):Sinocymodus xinpuensis Li(2000)以及某些尚待研究的类型。在所储藏的海百合化石中,以重新厘定的许氏创口海百合Traumatocrinus hsui(Mu)[?=T.caudes(Dittmar,1866);?=T.guanlingensis Yu et al.]为主,新的发现说明,此类海百合营假浮游生活方式,它们通过其网状或铰接状根簇附着在漂浮树干上而广泛分布。共存的化石还有:新近发现和重厘定的Metapolygnathus nodosus带的牙形石,少量鱼类(Asialepidotus sp.nov.),大量软骨鱼类(elas-mobranch ichthyoliths)鳞片和牙齿化石的新类型,Trachyceras multituberculatus带的菊石,Halobia-“Daonella” bifurcata组合带的双壳类,以及腕足类:Koninckina guizhouensis,K.zhengfengensis等以及古植物化石:Equisetites arennaceus,Ctenozamites sarrani等。系统调查、科学发掘和对上述各门类化石时代综合分析后指,了这个珍稀生物群形成于晚三叠世卡尼期早-中期,主要产在新铺乡黄土塘、小凹、毛凹、巴毛林和岗乌乡白岩一带小凹组下段,距5-11m的地层间隔中,其分布面积约200km^2。构造古地理及层序、生态、化学地层的综合研究说明,关岭生物群可能是伴随晚三叠世卡尼期早中期的海侵在南盘江裂陷槽盆西北角活动外陆棚边缘所形成的“避难所”中形成和发展起来的。随着海侵的扩大,海水的加深和有机质的过盛贮存所诱发的缺氧和海水的咸化事件,可能是导致该生物群的集群绝灭,并形成完好保存埋藏群落的主要原因。  相似文献   

5.
凯里生物群中始海百合类形态功能、生态及埋藏特征初探   总被引:3,自引:0,他引:3  
贵州剑河八郎中寒武世凯里生物群中始海百合十分丰富,化石标本多达1万多件,分属长茎型的卢氏中国始海百合(Sinoeocrinus Zhao, Huang et Gong,1994)及短茎型的球形中国始海百合(Sinoeocrinus globus Zhao et al, 1999)。它们均具有腕枝、萼、茎及吸盘,少数标本见有肛锥。幼年体缝孔不发育,成年体具有较发育的缝孔。大部分个体为单体生活。短茎型的萼呈球形,茎短,吸盘大,常固着在腕足动物外壳及三叶虫背壳碎片上。长茎的萼呈长椭圆球形茎长,吸盘小,常固着在砂泥质海底。两个种的腕肢也有差别,长茎的直长,短茎的旋转生长,显示两个种的形态差别及多样性。由于始海百合死亡后迅速被掩埋,80%以上的个体保存完整。化石大部分保存无定向性,显示静水环境,海底紊流很少,不仅显示原地埋藏特征,也为凯里生物群是原地埋藏提供了重要证据。  相似文献   

6.
陡山沱藻Doushantuophyton Chen et Xiao是湖北秭归庙河埃迪卡拉系陡山沱组及安徽休宁埃迪卡拉系蓝田组中常见的种群,该属先后建立了5个种:D.lineare Chen et Xiao,1991;D.rigidulum,Chen1994;D.sinuolatum Hu,1996;D.quyuaniChen,Xiao and Yuan,1994,emend.Xiao et al.,2002和D.cometa Yuan et al.,1999。本文对贵州凯里组苗板坡剖面和乌溜-曾家崖剖面的30多块标本进行了详细描述,并与湖北庙河陡山沱组和安徽休宁蓝田组的陡山沱藻进行对比,结果表明,该属的模式种D.lineare Chen et Xiao和D.cometa Yuan et al.的时代可延伸到寒武纪第3世(原中寒武世)凯里生物群,并成为凯里生物群宏观藻类中的重要种群之一。也反映从埃迪卡拉纪陡山沱期至寒武纪第3世,经历了近5千多万年,特别是埃迪卡拉纪末期的生物灭绝事件,这2种的形态结构特征没有发生明显变化,说明陡山沱藻有些种具有较强的生存竞争能力以及遗传上的稳定性,从而表现出演化上的保守性和环境上的适应性。  相似文献   

7.
本文记述了一类新发现于贵州省盘州地区的中三叠世Anisian期乌蒙龙属新种。通过对一具鳍龙类标本进行描述,并与现已知盘县生物群鳍龙类对比后发现,这一新标本的骨骼形态整体特征与乌蒙龙属Wumengosaurus特征基本相似,具有狭长的吻部,显著多于其他鳍龙类的牙齿数量。但标本在细部特征上与乌蒙龙属模式种的纤颌乌蒙龙Wumengosaurus delicatomandibularis Jiang et al,2008有着显著的差异:其间腕骨intermedium呈扁平的圆形,牙齿呈细长的尖锥状,无冠部膨大。且标本与纤颌乌蒙龙Wumengosaurus delicatomandibularis Jiang et al,2008在掌骨、跖骨形态等方面也有着不同的特征。现依据该标本特征建立乌蒙龙属新种圆腕乌蒙龙Wumengosaurus rotundicarpus,spnov 。  相似文献   

8.
节头虫属(Genus Arthricocephalus)的概念一直较为混乱,在为它的模式种乔氏节头虫(Arthricocephalus chauveaui)指定"选模"后,又进一步加剧。经对A.chauveaui的原始手标本上保存的所有三叶虫研究后,发现命名者Bergeron所附A.chauveaui的唯一图片,依据的是其中一枚背壳,特征吻合,从而认定该背壳是A.chauveaui的正模,代表了模式种和节头虫属的概念,是该种和该属名称的载体。也表明为A.chauveaui建立"选模",既无必要,也违背命名者的本意。而且选择一个不归属于A.chauveaui的标本来代表该种、该属的概念,就更不妥当。经研究,手标本上的三叶虫不是同一个种,而是隶属于三个不同种,这三个种又应归属于三个不同的属,即Arthricocephalus,Oryctocarella和Duyunaspis。A.chauveaui"选模"头盖并不属于该种,应归属于Oryctocarella duyunensis。研究还表明,有三个分类单元是Arthricocephalus的晚出异名,即Arthricocephalus(Arthricocephalites)Chien et Lin in Lu et al.,1974,Haliplanktes Blaker et Peel,1997,和Arthricocephalites Chien et Lin sensu Yuan et al.,2002。  相似文献   

9.
关于创口海百合(Traumatocrinus)的分类、分布及古生态   总被引:1,自引:0,他引:1  
在中国贵州关岭地区晚三叠世(卡尼期)小凹组(=瓦窑组)海生爬行动物和海百合化石库中产有大量完好保存的创口海百合(Traumatocrinus)(棘皮动物门,海百合纲)化石。根据对此类海百合分类、分布和形态构造及古生态的研究,特别是大量完好保存、且附着在漂浮木头上的群体化石标本的发现,进一步证明这种外形似海百合花的创口海百合营假浮游的生活方式。这类特化的海百合分枝起源于另一类底栖中三叠世石莲海百合科,很快占领了卡尼期初期的生态境,至卡尼期末创口海百合衰退以后,它的生态境在诺利期时为形态发生的趋同变异的链海百合(Seirocrinus)和五角海百合(Pentacrinites)所占领。  相似文献   

10.
贵州上三叠统瓦窑组海百合化石群中的一新种   总被引:4,自引:0,他引:4  
王柏艳  白志强  郝维成  孙元林  江大勇 《现代地质》2002,16(3):231-236,T003,T004
在贵州省关岭地区上三叠统瓦窑组地层中发现了保存完好的海百合化石群。化石保存在瓦窑组近底部的深灰色—灰黑色泥质灰岩层面上 ,与海百合共生的有菊石、双壳类和牙形石等海洋生物。海百合化石数量丰富 ,保存完好 ,经鉴定分属于创孔海百合属 (Trauma tocrinusW hrmann ,1889emend .Mu ,194 9)的许氏创孔海百合 (Traumatocrinushs櫣iMu ,194 9) ,关岭创孔海百合 (TraumatocrinusguanlingensisYu ,2 0 0 0 )和新铺创孔海百合(Traumatocrinusxinpuensissp .nov .)。其中 ,新铺创孔海百合 (Traumatocrinusxinpuensissp .nov .)为一新种 ,该种成年个体较大 ,茎板厚度分 5级 ,各级茎板排列顺序为 (1为一级茎板 ;2为二级茎板 ,以此类推 ) :1、 5、 4、 5、 3、 5、 4、 5、 2、 5、 4、 5、 3、 5、 4、 5、 2、5、 4、 5、 3、 5、 4、 5、 2、 5、 4、 5、 1,一级茎板数与二级茎板数之比为 1/ 3。第一个粗羽枝分出在三级腕的第 3块腕板上。据其骨骼排列的精密程度 ,推测该种海百合适合于水动力较弱的海洋环境  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.
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   

13.
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   

14.
HYDROGEOLOGY     
正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level  相似文献   

15.
正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),  相似文献   

16.
17.
正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-  相似文献   

18.
正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-  相似文献   

19.
正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)  相似文献   

20.
GEOCHEMISTRY     
正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861  相似文献   

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