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1.
1 Introduction Sauropod dinosaurs were group of gigantic quadrupedal herbivores. This group includes the largest terrestrial animals ever to have existed. More than 120 genera have been proposed, however, many of these are now considered to be of dubious validity. Currently, approximately 100 genera are accepted as valid (Upchurch et al., 2004a). The sauropod dinosaur described herein was collected from Jiangyi (Fig. 1), Yuanmou County of Yunnan Province by the Yunnan Provincial Institute… 相似文献
2.
描述贵州独山星朗早石发世大塘期异珊瑚新属１个，新种１８个。本区异珊瑚类不仅有对环境专属性较强的一些异珊瑚新属种。还方对环境专属性较小的一些广布性属种。它们与贵州威宁、广西隆林的异珊瑚化二相比．普遍外壁厚，隔壁显著加厚及横板密集，说明这些异珊瑚是在水动力条件较强的开阔台地生活。 相似文献
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发现于内蒙古鄂托克旗召稍早白垩世罗汉洞组的一件不完整翼龙类下颌标本,以下颌愈合部长且平直、齿骨侧嵴发育、近圆形齿窝沿侧嵴之上的齿骨侧面上半部分自前向后呈直线排列、齿窝直径(2~2.5 mm)前后变化较小、相邻齿窝的间距约为齿窝直径的一半、下颌牙齿密度为3枚/cm等特征,可归入梳颌翼龙科(Ctenochasmatidae),且代表一新属种——郝氏鄂托克翼龙Otogopterus haoae gen.et sp.nov.。该化石是继鄂托克旗新召准噶尔翼龙科的平颌鄂尔多斯翼龙Ordosipterus planignathus之后在内蒙古鄂尔多斯地区发现的第2件确切翼龙类材料,丰富了这一地区早白垩世脊椎动物群的组成。该翼龙也是继甘肃庆阳环河翼龙Huanhepterus quingyangensis之后在鄂尔多斯盆地发现的第2种梳颌翼龙科化石,进一步扩大了鄂尔多斯盆地梳颌翼龙科的地理分布范围,同时表明鄂尔多斯盆地是继辽宁西部之后梳颌翼龙科在中国的又一重要分布区。 相似文献
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XUE Jinzhuang 《《地质学报》英文版》2009,83(3):504-512
Abstract: Two zosterophyll plants are described from the Lower Devonian (Lochkovian) Xitun Formation of Qujing, Yunnan, China. Xitunia spinitheca gen. et sp. nov. has stalked sporangia laterally attached on the axis in a helical arrangement. Sporangia are dorsoventrally flattened and composed of two unequal valves; the adaxial valve is round in face view, while the abaxial valve is larger than the former, triangular or wedge-shaped, and radially bears long spiny appendages along the distal margin. Xitunia shows new variation of sporangial morphology within the zosterophylls. Zosterophyllum minorstachyum sp. nov. has K-shaped branchings at the basal parts and small-sized terminal spikes, which consist of round to elliptical sporangia arranged helically. This paper provides new data on the diversity of plant types during Lochkovian when rare vascular plants were reported. As for various species of Zosterophyllum in South China, their apparent evolutionary trend of features from the Late Silurian to Early Devonian (Emsian) is discussed. 相似文献
5.
HAO Shougang WANG Deming WANG Qi XUE Jinzhuang 《《地质学报》英文版》2006,80(1):11-19
A new plant, Zhenglia radiata gen. et sp. nov., from the Posongchong Formation （Early Devonian, Pragian age） of the Wenshan District of southeastern Yunnan Province, China is a small herbaceous lycopsid. The aerial branches divide into foliar and fertile stems. The arrangement of the leaf bases on the stem shows lepidodendroid-like phyllotaxy. Possibly the leaf base bears a ligulate pit. The microphyll consists of a swollen, decurrent base, and an entire, linear lamina. The fertile axis is composed of sporophylls arranged helically, forming a compact area similar to cone-like structure. Each sporophyll consists of a widened lateral extension and a distal lamina. The ovoid-elongate sporangia are attached adaxially on the surface of sporophylls. Based on morphological similarities, especially the undivided microphylls, the style of phyllotaxy, the form of the cone-like structures and sporangia, the new lycopsid Zhenglia radiata is placed in the order Protolepidodendrales and a possible evolutionary relationship with the arborescent lycopsids of the Late Devonian and Carboniferous is considered. 相似文献
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SEM analysis of trunk ornamentation on a compressed palaeoscolecid fossil from the Shipai fauna, Cambrian Series 2 and Stage 4 at Three Gorges, South China, allows a reassignment of the material to a new taxon, Sanxiascolex papillogyrus gen. et sp. nov. The preserved body is entirely annulated. Each annulus is ornamented by four rows of irregularly alternating plates and each plate bears numerous tubercles at the marginal region and a variable number (zero to six) of nodes at its central part. These features are unique among known palaeoscolecids. Comparative analyses with other compressed palaeoscolecid macrofossils and phosphatized material on the pattern of trunk ornamentation indicates that a detailed examination of the cuticle ornament weighs heavily in analyses of their taxonomic distinctions. A similar sclerite pattern to that of S. papillogyrus has been found in some phosphatized palaeoscolecid cuticle fragments as well as in isolated sclerites. The upper series of nodes and tubercles of these sclerites suggest an accretional mode of sclerite growth. The considerable variation in node number observed across the plates of S. papillogyrus demonstrates that phosphatic palaeoscolecid taxonomy based on?relatively?minor variations in?the number of sclerite nodes?should perhaps be reconsidered. As the origins of the phosphatized specimens are quite diverse, a large variety of isolated sclerites from the Early Palaeozoic may not reflect actual biodiversity. 相似文献
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1981年6月,谢守江等在四川珙县巡场火车站采石场的下二叠统栖霞组近底部,采获一大型旋壳鹦鹉螺化石,由王雪龙等提供笔者研究。现将采样地点地层剖面简列于后。 相似文献
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JIN Peihong MAO Teng DONG Junling WANG Zixi SUN Mingxuan XU Xiaohui DU Baoxi SUN Bainian 《《地质学报》英文版》2017,91(4):1200-1214
Cupressinocladus Seward is a fossil genus of conifers and conifer fossils with reproductive organs are very rare. In general, it is difficult to understand the natural affinities with other conifers. In this paper, a new species, Cupressinocladus guyangensis P.H. Jin et B.N. Sun sp. nov., is reported based on branches with immature female cones from the Lower Cretaceous Guyang Formation of the Guyang Basin in Inner Mongolia, northern China. The foliage shoots are decussate. Leaves are decussate, imbricate, scale-like, weakly dimorphic, and bear longitudinal glands on the abaxial view. Stomata complexes are haplocheilic, monocyclic, irregularly arranged, and spread along the leaf margin. Immature female cones are subglobose with 6–8 cone scales, and three subglobose ovules arranged in a row at the base of the cone scales. Moreover, we performed cluster analysis using a statistics and machine learning toolbox for 23 fossils and extant species based on 16 morphological characters. The result implies that the new species bears a close resemblance to the extant Cupressus funebris Endl. and might have nearest systematic affinities to it. 相似文献
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Anneke H. van Heteren Mietje Germonpré 《Boreas: An International Journal of Quaternary Research》2023,52(4):498-506
The Namur area in Belgium is useful to study brown (Ursus arctos) and cave bears (Ursus spelaeus) as the assemblage contains little temporal and no geographical variation. Here, we aim to assess ontogenetic allometry within cave bears, as well as ecomorphological differences between adult brown bears (n = 9), adult cave bears (n = 5) and juvenile cave bears (n = 3). Landmarks for 3D digitization of the mandible were chosen based on the taphonomical damage of the specimens. Extant brown bears and extinct Pleistocene brown and cave bears were digitized with a Microscribe G2. Generalized Procrustes superimposition was performed on the coordinates. Allometry was studied using regression analysis. Principal component analysis (PCA) was conducted to assess ecomorphological differences between the groups. 61% of the shape variance within juvenile and adult cave bears was predicted by size (n = 8, p < 0.01). The juvenile cave bears have relatively deep horizontal rami. In adult cave bears, the horizontal ramus is much narrower dorsoventrally. Juvenile cave bears have a small masseteric fossa and a short coronoid process, whereas both are larger, relative to mandible size, in adult cave bears. This made juvenile cave bears likely less effective masticators than fully grown cave bears. In the PCA, principal component (PC) 1 accounts for 45.0% of the total variance and PC2 accounts for 27.6%. Fossil U. arctos from Namur fall within the 95% confidence interval of modern North American U. arctos on both PCs, but are more similar to cave bears than the average extant brown bear. From the similarity of fossil and modern brown bears, it can be deduced that the diet of fossil brown bears was probably also within the range of their modern North American conspecifics, although they might have been more efficient at masticating plant matter. 相似文献
10.
XU Li WU Xiaochun Lü Junchang JIA Songhai ZHANG Jiming PU Hanyong ZHANG Xingliao 《《地质学报》英文版》2014,88(4):1041-1050
Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanehuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3^rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3^rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only. 相似文献
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Jianjun Shi Jicheng Feng Rui Peng Quanjie Zhu 《Geotechnical and Geological Engineering》2022,40(6):3357-3364
Geotechnical and Geological Engineering - The gob-side entry driving is driving in low pressure area, which bears less support pressure and is easy to maintain, so it is widely used. Taking the... 相似文献
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Natural Hazards - The fault fracture zone, featuring a variety of fault rocks and associated fissures, is a special area which bears the most concentrated stress when it forms and develops. It is... 相似文献
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幔源铀成矿作用的地球化学证据——以下庄小水“交点型”铀矿床为例 总被引：8，自引：0，他引：8
文章以小水铀矿床为例,探讨了下庄矿田"交点型"铀矿成矿物质来源。研究表明:(1)小水"交点型"铀矿床矿石主要由沥青铀矿、方解石和萤石等矿物组成,方解石产于矿脉两壁,萤石和沥青铀矿沉淀于矿脉中间部位;(2)沥青铀矿年龄为71.8~75.2 Ma,与围岩基性脉岩(120~100Ma)之间存在较大的矿岩时差;(3)萤石中流体包裹体的δD为-124.44‰~-97.08‰,δ18OSMON为7.40‰~11.02‰,具有幔源同位素组成特征;(4)在微量元素地球化学特征上,矿石与辉绿岩表现出相似性,与下庄花岗岩则具有明显的差异。笔者认为,下庄矿田小水"交点型"铀矿床成矿流体中的矿化剂来自地幔,铀源可能直接来自与辉绿岩具有相似源区性质的富集地幔;推测铀的沉淀成矿与富含CO2、F、H2S、U等组分的超临界态成矿流体在临界点附近发生沸腾作用相关。 相似文献
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本文描述了产自中国辽宁省北票市早白垩世义县组一新的伤齿龙类化石——柯氏辽宁猎龙(Liaoningvenator curriei gen. et sp. nov.)。它具有伤齿龙类以下特征: 数量众多且密集的上颌齿与下颌齿; 牙齿的齿冠与齿根之间显著收缩; 齿骨侧表面具有一沟, 营养孔位于该沟内; 远端尾椎背部的神经棘减弱为一个沟。它不同于其它伤齿龙类的特征主要为坐骨靴大, 侧面观近乎三角形, 坐骨闭孔突细长; 尾椎形态转变点位于第7尾椎。系统发育分析表明柯氏辽宁猎龙与短羽始中国羽龙(Eosinopteryx brevipenna)构成姊妹群, 位于同一分支内。它们具有如下共同特征: (1)上颌骨和下颌骨前面部分的牙齿前隆无锯齿; (2)颈肋较其相关节的椎体长; (3)肠骨前缘直。辽宁猎龙代表了辽西同等层位发现的第5个伤齿龙类。骨组织研究显示辽宁猎龙的骨骼已接近成熟, 死亡时至少4岁。它为该地区的基干伤齿龙类恐龙提供了新的解剖学信息, 并丰富了目前中国已知早白垩世伤齿龙类的多样性。 相似文献
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Andrei V. Sher Jacobo Weinstock Gennady F. Baryshnikov Sergey P. Davydov Gennady G. Boeskorov Vladimir S. Zazhigin Pavel A. Nikolskiy 《Quaternary Science Reviews》2011,30(17-18):2238-2249
For a long time, “spelaeoid” (cave-bear-like) bears, Ursus (Spelearctos) spp., were believed to be almost purely European animals. Their geographic range has recently been extended to the east, in southern Siberia, Transbaikalia, Kirghizia, Mongolia and Korea. Two unexpected new findings, presented here in detail, significantly change existing views on the distribution of cave bears; both were found in North-Eastern Siberia, far beyond the Arctic Circle, more than 1500 km to the north-east of the previously accepted range.One of the fossils is a mandible, found near the town of Cherskiy at 68.73°N, 161.38°E. The analysis of local geology and accompanying mammal fossils suggests that it comes from the Olyorian Fauna (Early to early Middle Pleistocene). Morphologically, the Cherskiy mandible is closest to Ursus savini, a small middle Pleistocene cave bear from the British Cromer Forest-bed Formation, but differs in having a slightly more advanced dentition, and thus it is described as a new subspecies Ursus savini nordostensis. Another newly recognized fossil of the “spelaeoid” bear is an astragalus found at the Oskhordokh site at 67.54°N, 135.67°E, on a large gravel bar on the right bank of the Adycha River. This specimen is attributed to Ursus cf. deningeri.The paper also presents an interesting example of the interaction between classical and “molecular” palaeontology.The new finds significantly change existing ideas on the ecology and evolution of cave bears, some of the most remarkable members of the extinct Pleistocene megafauna. 相似文献
16.
Doklady Earth Sciences - A new dromaeosaurid theropod dinosaur, Kansaignathus sogdianus gen. et sp. nov., is described based on a dentary from the Yalovach Formation (Santonian) at Kansai locality... 相似文献
17.
Ommatidae is a small, but ancient, basally nested family of the hyper-diverse beetles (Coleoptera). Here, a remarkable new taxon, Paraodontomma burmitica gen. et sp. nov., is described based on a well-preserved specimen in Upper Cretaceous Burmese amber. Based on a wider epipleural rim on each elytron, the new genus belongs to the extinct tribe Brochocoleini. This finding further reinforces the idea that the Burmese paleofauna of ommatid beetles was much more diverse and abundant than previously thought. 相似文献
18.
John Davison Simon Y.W. Ho Sarah C. Bray Marju Korsten Egle Tammeleht Maris Hindrikson Kjartan Østbye Eivind Østbye Stein-Erik Lauritzen Jeremy Austin Alan Cooper Urmas Saarma 《Quaternary Science Reviews》2011,30(3-4):418-430
This review provides an up-to-date synthesis of the matrilineal phylogeography of a uniquely well-studied Holarctic mammal, the brown bear. We extend current knowledge by presenting a DNA sequence derived from one of the earliest known fossils of a polar bear (dated to 115 000 years before present), a species that shares a paraphyletic mitochondrial association with brown bears. A molecular clock analysis of 140 mitochondrial DNA sequences, including our new polar bear sequence, provides novel insights into the times of origin for different brown bear clades. We propose a number of regional biogeographic scenarios based on genetic data, divergence time estimates and paleontological records. The case of the brown bear provides an example for researchers working with less well-studied taxa: it shows clearly that phylogeographic models based on patterns of modern genetic variation alone can be substantially improved by including data on historical patterns of genetic diversity in the form of ancient DNA sequences derived from accurately dated samples and by using an approach to divergence-time estimation that suits the data under analysis. Using such approaches it has been possible to (i) establish that the processes shaping modern genetic diversity in brown bears acted recently, within the last three glacial cycles; (ii) distinguish among hypotheses concerning species’ responses to climatic oscillations in accordance with the lack of phylogeographic structure that existed in brown bears prior to the last glacial maximum (LGM); (iii) reassess theories linking monophyletic brown bear populations to particular LGM refuge areas; and (iv) identify vicariance events and track analogous patterns of migration by brown bears out of Eurasia to North America and Japan. 相似文献
19.
混合原油的地球化学特征及成藏贡献率 总被引：1，自引：0，他引：1
含油气盆地中存在混合原油的现象非常普遍,按照形成条件可区分出4种不同的混合类型.地球化学研究表明不同有机相原油混合后体现各自母源的生物标志化合物组合特征;生物降解原油与正常原油混合后具有完整的饱和烃谱峰,同时还反映生物降解特点;不同成熟度的原油混合后既可检出热稳定性低的化合物,部分成熟度参数还可指示成熟特征;高成熟天然气与原油混合后,往往会使不同组分段的成熟度产生明显变化.特殊化合物绝对浓度定量法、生物标志化合物参数法、碳同位素法和拟合图版法是常见的定量成藏贡献率方法.针对混合原油地球化学识别和贡献率定量中的局限性,提出了利用指纹技术进行优化的思路. 相似文献
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