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1.
Exceptionally preserved Mesozoic feathered dinosaur fossils (including birds) are famous, but recognized from only very few localities worldwide, and are especially rare in the Southern Hemisphere. Here we report an assemblage of non-avian and avian dinosaur feathers from an Early Cretaceous polar (around 70°S) environment in what is now southeastern Australia. The recovered remains incorporate small (10–30 mm long) basal paravian-like tufted body feathers, open-vaned contour feathers, and asymmetrical bird-like wing feathers that possess high-angled barbs with possible remnants of barbicels — amongst the geologically oldest observed to date. Such morphological diversity augments scant skeletal evidence for a range of insulated non-avian theropods and birds inhabiting extreme southern high-latitude settings during the Mesozoic. Although some of these fossil feathers exhibit what may be residual patterning, most are uniformly toned and preserve rod-shaped microbodies, as well as densely-packed microbody imprints on the barbules that are structurally consistent with eumelanosomes. Geochemical analysis detected no identifiable residual biomolecules, which we suspect were lost via hydrolysis and oxidization during diagenesis and weathering. Nevertheless, an originally dark pigmentation can be reasonably inferred from these melanic traces, which like the coloured feathers of modern birds, might have facilitated crypsis, visual communication and/or thermoregulation in a cold polar habitat.  相似文献   

2.
中国中生代鸟类研究概述   总被引:3,自引:0,他引:3  
侯连海  顾玉才等 《江苏地质》1999,23(3):T001-T005
对最近轰动世界的我国中生代鸟类化石的系统结果表明,中国是目前中生代早期鸟类化石产地和化石发现最多的地区,从晚侏罗世到早白垩世存在两个亚纲的鸟类分子,晰鸟亚纳(Sauriurae)和今鸟亚纲(Ornithurae),鸟类从爬行动物分化出来不久即分为两大支系向前演化,孔子鸟(Confuciusornis)和辽宁鸟(Liaoningornis)的发现证明,始祖鸟(Archaeopteryx)只是鸟类进化的一个旁支,不是最早的鸟类,孔子鸟代表鸟类向飞行进行的主流,辽宁鸟是目前今鸟亚纲最早的代表,鸟类在进化过程中渐变和突变同时并存,鸟类的历史应大大向前推移。  相似文献   

3.
AbstractAn incomplete caudal vertebral series (IVPP Vl1309) from the Yixian Formation of late MesozoicJianshangou area of Beipiao, western Liaoning Province, may represent a new bird. The tail is composed of at least 12 free caudal vertebrae and the most distal 5 caudal vertebrae co-ossified into a pygostyle. The pygostyle is plate-like and slightly curved dorsally. The anterior free caudals are amphiplatyan. The anterior caudal surfaces of the last three free caudals are concave, but their posterior articular surfaces are convex. The pygostyle is regarded as the first appeared flight apparatus during the evolutionary process from Archaeopteryx to neornithes. The pygostyle appeared in most early fossil birds and almost all the modem birds. Although their morphologies are different, they are basically formed by at least four last caudal vertebrae. The specimen V11309 is regarded as a bird rather than a non-avian theropod dinosaur based on the following characters: short caudal vertebrae, numerous pits present on the surfaces of the centra and, a foramen present between the basal part of the fused neural spines, which is similar to that of Struthio camelus. The discoveries of pygostyles from the therizinosauroids and oviraptorosaurs may provide strong evidence for supporting the origin of birds from small theropod dinosaurs. The structure of the pygostyle in specimen Vl1309 is different from those of Beipiaosaurus (Therizinosauroid) and Nomingia (oviraptorosaur). The most parsimonious interpretation is that these pygostyle-like structures are independently acquired by Beipiaosaurus and Nomingia during their evolutionary process.  相似文献   

4.
鸟类栖息行为是鸟类重要的生活习性,与鸟类后肢骨骼的形态结构之间存在密切的适应演化关系,而中生代鸟类栖息行为的分析推断也是古鸟类学研究的热点。文中通过对大量现生鸟类的后肢骨骼系统进行形态学对比、统计学分析,分别以后肢3块骨骼的长度变化、跗跖骨远端跖骨滑车的特征差异、第Ⅲ趾趾节长度变化规律和第Ⅲ脚爪爪弧的弧度大小为研究对象,并与其对应的栖息行为分别进行分析判断,然后将判断特征和有效变量运用于中生代鸟类栖息行为的推理中。通过系统的分析研究,对中生代鸟类的栖息行为得出如下的推断:大量基干鸟类的栖息习性是以攀援为主,只有少数可以树栖生活,反鸟类的栖息习性十分接近树栖鸟类,今鸟类的栖息行为兼有树栖、地栖的习性。  相似文献   

5.
Continental- Margin Structure of Northeast China and Its Adjacent Areas   总被引:10,自引:0,他引:10  
The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the i  相似文献   

6.
贵州省拥有丰富的中生代脊椎动物化石记录,多为三叠纪海生爬行类化石,侏罗纪和白垩纪的脊椎动物化石较少。目前,贵州省已发现中生代爬行类足迹点9处,分别为贞丰牛场、贞丰龙场、安顺幺铺、赫章辅处、毕节响水(2处)、仁怀茅台、赤水宝源和习水同民足迹点。文中除描述了贞丰龙场新增的一批足迹化石外,整理并总结了所有足迹点的发现史、研究现状、足迹类型与特征以及所反映的古生态信息。已发现的遗迹记录由69条行迹和420个孤立足迹组成,足迹总数达991个。所有的遗迹化石指示了至少477个造迹者,包括海生爬行类、手兽足迹类、非鸟兽脚类、鸟类、蜥脚类和鸟臀类等,其中三叠纪以海生爬行类主导,侏罗纪和白垩纪以蜥臀类主导。这个数据集为贵州中生代古生物类群的多样性提供了重要的信息,是晚中生代稀缺骨骼化石记录的良好补充,为研究贵州省中生代脊椎动物群的古生态与古环境提供了更多的证据。  相似文献   

7.
南海围区中生代构造古地理演化   总被引:1,自引:0,他引:1  
对南海围区中生代岩相、构造以及古地理进行了系统总结与研究,编制了南海围区6 个时期 ( 包括T3--K2 ) 构造古地理简图,阐述了南海围区主要的缝合带形成时间和中生代活动及其对南海围区中生代的古地理的控制与影响。经研究,南海围区盆地类型、中生界地层以及古地理环境受特提斯的闭合以及环太平洋俯冲带的影响控制。虽然南海的存在使F6 系列断裂有了现在的格局,但是古太平洋构造带一直控制着中生代加里曼丹、巴拉望、潮汕凹陷以及台湾等地的盆地的形成。讨论了南海及其围区中生代构造古地理的演化,南海围区地层从早侏罗世到晚侏罗世沉积相显示是由海相到陆相的转变,晚三叠世到晚白垩世每个时期都呈现北陆南海的古地理格局。  相似文献   

8.
A New Symmetrodont Mammal with Fur Impressions from the Mesozoic of China   总被引:3,自引:0,他引:3  
Western Liaoning of northeastern China is world-renowned for the Mesozoic Jehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossil angiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preserved hairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao, western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and life habits of Mesozoic symmetrodont mammals.  相似文献   

9.
南海北部陆缘中生代沉积层序、对比和油气地质意义   总被引:9,自引:3,他引:6  
南海北部陆缘陆上粤中-粤东地区出露一系列的中生界,可以划分为15个Ⅲ级沉积层序。在毗邻海区的潮汕坳陷的地震剖面和LF35-1-1井也可以识别出12个Ⅲ级沉积层序。这些Ⅲ级层序组成了6个Ⅱ级层序和2个Ⅰ级层序,反映出由海向陆的环境变化过程。陆区和海区中生界在岩性、岩相以及层序地层等方面存在可对比性。陆区上地层-沉积特征以及模式可以作为模型应用于海区中生界相关研究,对南海北部中生界油气勘探具有指导意义。  相似文献   

10.
In order to better understand the Mesozoic tectonic evolution of Southeast China Block (SECB in short), this paper describes geological features of Mesozoic basins that are widely distributed in the SECB. The analyzed data are derived from a regional geological investigation on various Mesozoic basins and a recently compiled 1:1,500,000 geological map of Mesozoic–Cenozoic basins. Two types of basin are distinguished according to their tectonic settings, namely, the post-orogenic basin (Type I) and the intracontinental extensional basin (Type II); the latter includes the graben and the half-graben or faulted-depression basins. Our studies suggest that the formation of these basins connects with the evolution of geotectonics of the SECB. The post-orogenic basin (Type I) was formed in areas from the piedmont to the intraland during the interval from Late Triassic to Early Jurassic; and the formation of the intracontinental extensional basin (Type II) connects with an intracontinental crustal thinning setting in the Late Mesozoic. The graben basin was generated during the Middle Jurassic and is associated with a bimodal volcanic eruption; and the half-graben or faulted-depression basin, filled mainly by the rhyolite, tuff and sedimentary rocks during Early Cretaceous, is occupied by the Late Cretaceous–Paleogene red-colored terrestrial clastic rocks. We noticed that the modern outcrops of numerous granites and basins occur in a similar level, and the Mesozoic granitic bodies contact with the adjacent basins by large normal faults, suggesting that the modern landforms between granites and basins were yielded by the late crustal movement. The modern basin and range framework was settled down in the Cretaceous. Abundant sedimentary structures are found in the various basins, from that the deposited environments and paleo-currents are concluded; during the Late Triassic–Early Jurassic time, the source areas were situated to the north and northeast sides of the outcrop region. In this paper, we present the study results on one geological and geographical separating unit and two separating fault zones. The Wuyi orogenic belt is a Late Mesozoic paleo-geographically separating unit, the Ganjiang fault zone behaves as the western boundary of Early Cretaceous volcanic rocks, and the Zhenghe–Dapu fault zone separates the SE-China Coastal Late Mesozoic volcanic-sedimentary basins and the Wuyi orogenic belt. Finally, we discuss the geodynamic mechanisms forming various basins, proposing a three-stage model of the Mesozoic sedimentary evolution.  相似文献   

11.
辽西首次发现保存毛发和软件的中生代哺乳动物化石   总被引:3,自引:2,他引:3  
季强 《地质通报》2002,21(1):29-34
中国辽西地区素以产出丰富多彩的中生代热河生物群闻名于世。特别是近几年来,该区大量长羽毛的恐龙、原始鸟类、原始哺乳类和被子植物化石的发现更加引起了国际科学界的极大关注。1997年秋,作者在辽宁北票四合屯地区发现了一块完整的保存有毛发和软体印痕的对齿兽类哺乳动物化石。身体保存有手发和软体印痕的中生代哺乳动物化石在世界上也是罕见的。对对于研究对齿兽形态结构、生物习性、系统关系等方面均具有重要意义。  相似文献   

12.
1 Introduction Enantiornithes were the most blooming branch among the early birds and had distinct diversities. They flourished in the Early Cretaceous (Kurochkim, 1985; Chiappe, 1991; Sanz and Bonaparte, 1992; Boles, 1995; Elzanowski, 1995), and become extinct at the end of the Late Cretaceous. Lots of the birds have been reported in western Liaoning, China (Sereno and Rao, 1992; Zhou, 1995; Hou, 1996, 1997; Sanz and Chiappe, 1996; Sanz et al., 1997; Hou and Chen, 1999; Hou et al., 1…  相似文献   

13.
辽西地区中生代环境变迁及生物演替   总被引:3,自引:1,他引:3  
对辽西中生代盆地沉积相及地球化学特征的分析表明,辽西地区在中生代经历了复杂的环境变迁,从早期(晚三叠世-中侏罗世)的温暖潮湿气候环境过渡到中期(晚株罗世)干旱少雨的气候环境,最后再次过渡到晚期(早白垩世)温暖潮湿气候环境,其间发育有三次较大的火山作用;气候环境的巨变引起生物演化的更替,强烈的义县组火山作用一方面造成脊椎动物的集群灭亡,另一方面导致热河生物群的繁盛;早期鸟类的出现也是这一特定环境下的产物。  相似文献   

14.
15.
The First Mesozoic Heterodactyl Bird from China   总被引:1,自引:1,他引:0  
1 Introduction Enantiornithines were the dominant birds nearly worldwide throughout the entire span of the Cretaceous (Chiappe, 1995; Feduccia, 1996). The adaptive radiation of opposite birds is little known besides the disparity of rostral morphology in Boluochia (Zhou, 1995), Longipteryx (Zhang et al., 2001), Longirostravis ( Hou et al., 2004), and the presence of stomach contents that reflect a diversity of diets. Like the structure of rostrum, differentiation of the locomotor apparatu…  相似文献   

16.
为了查清喀左县双庙地区古生物化石的种类、数量及确切赋存层位,通过野外地质调查、剖面测量和挖掘发掘坑,在双庙地区中生界采获大量的爬行类、鸟类、鱼类及古植物等化石,对比分析认为,其产出层位为下白垩统九佛堂组一段,埋藏于湖泊相沉积环境。该研究成果丰富了辽西中生代古生物化石资料。  相似文献   

17.
In order to ascertain the species, quantity and occurrence layers of the fossils specimens in Shuangmiao region of Kazuo County, the authors harvested lots of Mesozoic fossils such as reptiles,birds,fishes and plant species, through geological surveys, section measurements and excavations. According to the comparison between the measured section and typical section, it is concluded that the fossil-bearing stratum is the No.1 Member of Jiufotang Formation, which belongs to the lacustrine facies. This research enriches the Mesozoic fossils data of Western Liaoning Province.  相似文献   

18.
渤张断裂带的构造机制及其地质意义   总被引:9,自引:1,他引:9       下载免费PDF全文
侯贵廷  叶良新 《地质科学》1999,34(3):375-380
渤张断裂带形成于中生代,为剪张性断裂带。中新生代以来渤张断裂带一直活动,并控制中新生代沉积和火山活动。中生代至老第三纪早期(42Ma 之前)渤张断裂带为右旋走滑的剪张性断裂带,而老第三纪中晚期以来(42Ma 以来)渤张断裂带转为左旋走滑的剪张性断裂带,并控制了渤海盆地的油气分布和现代的地震活动。近期,沿渤张断裂带地震活动频繁,说明渤张断裂带仍在活动。  相似文献   

19.
Burmaneura minuta gen. et sp. nov., the first araripeneurine antlion in amber, is characterized, described and compared with the modern and Mesozoic Myrmeleontidae. The precise position of the fossil within this group is debatable. Interestingly, despite a rather rich fossil record, all Mesozoic Myrmeleontidae belong to subfamilies that are not recorded in the Cenozoic, although this might merely reflect the artificiality of the classification as the extinct groups may be paraphyletic with respect to their younger counterparts (e.g., Araripeneurinae may very well be nothing more than a stem group of no classificatory value).  相似文献   

20.
王明健  潘军  高红芳  黄龙  李霞 《地学前缘》2022,29(2):294-302
目前的勘探成果表明,南海北部到东海南部的广阔海域普遍发育中生代地层,但是除了在台西南盆地发现工业油气藏之外,其他地区的中生界尚未有大的勘探突破。本次研究将中生代南海北部—东海南部作为一个整体,开展大地构造背景分析,厘清各构造时期盆地的性质及其形成演化机制,探讨油气资源潜力。结果表明:南海北部—东海南部从晚三叠世到白垩纪整体为一个大型盆地,盆地的演化受其周围板块相互运动所控制;晚三叠世(T3)主要受特提斯构造域控制,发育被动陆缘边缘海沉积盆地;从早侏罗世(J1)到早白垩世均受古太平洋板块(伊泽奈崎板块)向欧亚板块俯冲机制的控制,其中早—中侏罗世(J1-2)发育弧前坳陷盆地,晚侏罗—早白垩世(J3—K1)盆地性质为弧后断陷盆地;晚白垩世(K2)受太平洋板块、欧亚板块和印度板块的联合控制,性质依然为弧后断陷盆地,与前期相比,裂陷强度加大;海水由东南方向侵入,地层垂向上由海相向陆相逐渐过渡,由东南向西北和东北方向,水体逐渐变浅,亦由海相向陆相逐渐演变;中生界在南海北部潮汕坳陷等地区发育深海相和海湾相泥岩,在东海南部基隆坳陷也发育良好的海湾相泥岩,生烃潜力大,具有形成大型油气藏的物质基础和地质条件,勘探潜力巨大。本次研究结果可以为南海北部—东海南部中生界的油气资源勘探提供依据。  相似文献   

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