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A deep-bodied ginglymodian fish from the Middle Triassic of eastern Yunnan Province,china,and the phylogeny of lower neopterygians

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Science Bulletin 2012年第1期57卷 112-121页

作者： XU GuangHui * &WU FeiXiang key laboratory of Evolutionary Systematics of Vertebrates,institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,Beijing 100044,china

The Ginglymodi are a group of ray-finned fishes that make up one of three major subdivisions of the infraclass ***- tant ginglymodians are represented by gars,which inhabit freshwater environments of North and Central America and ***, we report the discovery of well-preserved fossils of a new ginglymodian,Kyphosichthys grandei *** ***.,from the Middle Triassic(Anisian)marine deposits(Guanling Formation)in Luoping,eastern Yunnan Province,*** discovery documents the first known fossil record of highly deep-bodied ginglymodians,adding new information on the early morphological diversity of this *** studies of functional morphology of extant deep-bodied fishes indicate that Kyphosichthys is not a fast swim- mer but has a good performance in precise maneuvering,representing a morphological adaptation to structurally complex habitats (*** macrophyte beds,rocky areas,or coral reefs),which differs from the other members of this group.A cladistic analysis with the new fish taxon included supports the hypothesis that the Ginglymodi are more closely related to the Halecomorphi than to the *** by Felberia,Kyphosichthys,and Dapedium,a highly deep and short fish body type has inde- pendently evolved at least three times in the stem-group neopterygians,ginglymodians,and basal teleosts within the lower neop- terygians of the Triassic.

关键词： deep-bodied fish Osteology Semionotidae Ginglymodi Holostei

Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2,FANG Xiaomin 1,2,GAO Junping1, NIE Junsheng1,YAN Maodu1,3,XU Xianhai1 & SUN Dong1 1. MOE National laboratory of Western china抯 Environmental Systems & College of Resource and Environment,Lanzhou University,Lanzhou 730000,china 2. state key laboratory of Loess and Quaternary geology ,institute of Earth Environment,chinese academy of sciences,Xi抋n 710075, china 3. Department of Geological sciences,University of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National laboratory of Western china\'s Environmental Systems & College of Resource and Environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3An *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.25,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the chinese elephant Anancus sinensis are firstly constrained at about 5.25 MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

Linking the Sulu UHP belt to the Korean Peninsula:Evidence from eclogite,Precambrian basement,and Paleozoic sedimentary basins

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Linking the Sulu UHP belt to the Korean Peninsula:Evidence f...

中国科学院地质与地球物理研究所2007学术年会

作者： Mingguo Zhai~(a,b,*),Jinghui Guo~(a,b),Zhong Li~a,Daizhao Chen~a,Peng Peng~a,Tiesheng Li~a, Quanlin Hou~c,Qicheng Fan~d a institute of geology and Geophysics,and key laboratory of Mineral Resources,chinese academy of sciences,Beijing,100029,china b chinese state key laboratory of Lithosphere Evolution,china c Graduate University,chinese academy of sciences,china d institute of geology,chinese Seismological Bureau,china

Considerable debate on whether and how the Sulu Orogenic Belt extends eastward to the Korean Peninsula has remained over the past decade. New results reported here include the following:(1) an eclogite and retrograded eclogite-bearing complex(Hongseong Complex) is discovered in South Korea,in which the eclogite occurs as lenses in circa～810-820 Ma granitic *** zircon dating of the eclogite yields～230 Ma for the metamorphic age and～880 Ma for the protolith age;(2) The basement of the Rangnim,Gyeonggi and Yeongnam massifs have affinities to, the basement of the North china Block(NCB).However the Gyeonggi Massif encloses a minor amount of large or small slabs of the Hongseong Complex that are similar to the rocks of the Sulu Belt.(3) Two main Paleozoic basins within the Rangnim and Gyeonggi massifs have a similar Paleozoic tectono-stratigraphy to the NCB.(4) The Imjingang and Ogcheon belts do not exhibit any metamorphic characteristics of collisional orogenic *** on these facts,we propose a crustal-detachment and thrust model and suggest that the collision belt between the Yangtze Block(YB) and NCB(Sino-Korea Craton) is preserved along the western margin of the Korean *** lower part of the UHP metamorphosed lithosphere of the YB was subducted under the Korean Peninsula and not uplifted to the *** lower crust of the YB(the Hongseong Complex) was detached from the subducted lithosphere and thrust over the Korean Peninsula,and inserted into the basement rocks of the Gyeonggi *** upper crust of the YB possibly was detached from the lower crust and overthrusted along the Honam and Chugaryong shear *** Imjingang and Ogcheon belts possibly represent the detached upper crust of YB and their present occurrences are controlled by a Mesozoic strike-slip shear *** these detached lower and upper crustal slabs were strongly deformed during the Late Jurassic and Early Cretaceous tectonic event leading to their present geologi

关键词： Korean Peninsula Sulu Belt Tectonic link Evidences Geotectonic significance

Composite stratigraphy of the Sailinhudong Group and Ore-bearing Micrite Mounds in the Bayan Obo Deposits,Inner Mongolia,china

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 357-369,506-507页

作者： Qiao Xiufu, Gao Linzhi, Peng Yang,institute of geology, chinese academy of Geological sciences,26 Baiwanzhuang Rd., Fuchengmenwai, Beijing 100037and Zhang Yuxu chinese academy of Geological sciences, Beijing 100037 Gao Linzhi institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Rd. Fuchengmenwai Beijing 100037 chinese academy of Geological sciences Beijing 100037 [?]Qiao Xiufu Born in 1930 and graduated from the Department of Geology Beijing College of Geology in 1953. He is now a senior research fellow on sedimentology event stratigraphy and sequence stratigraphy in the Institute of Geology CAGS.

Based on studies of sequence stratigraphy, event stratigraphy, biostratigraphy and lithostratigraphy, it is concluded that the Sailinhudong Group is a part of the Bayan Obo Group. Some trilobite fragments are first found in thin sections of the rock from the lower part of the Sailinhudong Group and some Ordovician acritarchs and chitinozoans are also found in this group. A formationa unit of carbonate seismites is first recognized in the upper part and a huge micrite mound is first identified at the top. Dolomite, the host rock of the super giant Bayan Obo Fe-Nb-REE deposits, is neither an igneous carbonatite nor a common bedded sedimentary carbonate, but a huge micrite mound. It has the same macroscopic characters as the micrite mounds at the top of the Sailinhudong Group, which suggests that they should be of the same horizon. According to the fossils, the Sailinhudong and Bayan Obo Groups should be of the Early Palaeozoic rather than the Middle Proterozoic. The new discovery and new idea will throw light on the explanation of the genesis of the supergiant Bayan Obo Fe-Nb-REE deposits.

关键词： Sailinhudong Group Bayan Obo Group seismite micrite mound

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陕西宁强原始锥石类五辐对称新属种的发现

微体古生物学报 2011年第2期28卷 244-249页

作者：刘云焕李勇邵铁全郑曦郑军王岗王洪强王侃长安大学西安710054 西北大学西安710069 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 新疆地勘局第九地质大队乌鲁木齐830000

陕西宁强宽川铺地区灯影组宽川铺段的原始锥石类Carinachitids中,新发现了五辐对称新属种——五分宁强锥石(新属、新种)Pentaconularia ningqiangensis *** ***.。本文对这一新属种进行了描记。结合前人发现的两辐对称、三辐对称、四辐... 详细信息

陕西宁强宽川铺地区灯影组宽川铺段的原始锥石类Carinachitids中,新发现了五辐对称新属种——五分宁强锥石(新属、新种)Pentaconularia ningqiangensis *** ***.。本文对这一新属种进行了描记。结合前人发现的两辐对称、三辐对称、四辐对称的Carinachitids系列标本,作者对原始锥石类分类方案进行了重新修订,新发现增加了我们对原始锥石类多样性的认识。

关键词：五分宁强锥石新属新种 Carinachitids 寒武系梅树村阶陕西南部

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Evidence for sea-level falls in the Permian-Triassic transition in the Ziyun area,South china

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Evidence for sea-level falls in the Permian-Triassic transit...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： WU YA-SHENG~*,JIANG HONG-XIA and FAN JIA-SONG institute of geology and Geophysics,chinese academy of sciences,Beijing,china

The sedimentology of three sections showing the Permian-Triassic(P-T) transition on an Upper Permian reef in Ziyun,Guizhou Province, southwest china provides evidence of sea-level fall in this *** P-T transition in the Gendan section,which covers a reef-front sequence, contains a subaerial exposure surface and various desiccation cracks(including rolled-up chips,in-chip cracks,pyramid cracks,vertical cracks and sheet cracks),indicating sea-level *** P-T transition in the Shitouzhai section,which covers a reef-core sequence,contains three micritic beds with abundant pseudomorphs of tabular gypsum crystals replaced by *** underlying centimetres of deposits are composed of fine-crystalline dolostone,and have a sharp contact with the underlying reef-core *** association of gypsum pseudomorphs and fine-crystalline dolostone suggests an origin related to a supratidal evaporative *** P-T transition in the Tanluzhai section,which covers a back-reef sequence,is fine-crystalline dolostone,and shows a laminated algal structure indicating tidal-flat *** middle part of the dolostone interval has become a collapse breccia composed of dolostone fragments and a matrix of micrites or crustose multi-generation calcite *** formation of the collapse breccia is interpreted to be related to the dissolution of the evaporite interbeds originally present between the thin dolostone *** formation of the evaporite deposits requires a supratidal condition.

关键词： Permian-Triassic boundary P-T transition subaerial exposure sea-level fall end-Permian Ziyun reef

Extinction pattern of reef ecosystems in latest Permian

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Extinction pattern of reef ecosystems in latest Permian

中国科学院地质与地球物理研究所2007学术年会

作者： WU YaSheng~(1+),FAN JiaSong~1,JIANG HongXia~1 & YANG Wan~2 1 institute of geology and Geophysics,chinese academy of sciences,Beijing 100029,china 2 Department of geology,Wichita state University,1845 Fairmount,Wichita,KS 67260,USA

Studies of two Permian-Triasslc boundary(PTB) sections on top of a Changhsingian reef in Ziyun, Guizhou Province,southwestern china indicate that the end-Permian mass extinction of reef ecosystems occurred in two *** first step is the extinction of all stenotropic organisms such as calcisponges and fusulinids in the latest Permian(in the Clarkina yini conodont zone).The biota after the first extinction is simple,comprising eurytropic organisms including microgastropods,ostracods,and some small burrowing organisms,or only algal *** the beginning of the Early Triassic(*** beginning of the Hindeodus parvus zone),the environments became anoxic,and the microgastropod dominated biota or algal mats disappeared,which constituted the second episode of the mass extinction. The biota after the second extinction comprises small spherical microproblematica,some kinds of specialized organisms tolerant of anoxic or oxygen-poor *** the environments became oxygenated,the specialized biota was replaced by a microgastropod-dominated simple *** the environmental conditions improved further,the simple biota was replaced by a diverse biota with normal -sized ammonoids,bivalves,and gastropods,representing restoration of normal oceanic conditions. Comparison with PTB sections in Dolomites,Italy and Meishan,Zhejiang Province shows that non-reef ecosystems had a similar first episode of mass extinction in the latest *** the case that oceanic anoxia happened,non-reef ecosystems had a second extinction episode similar to that of reef ecosystems.

关键词： end-Permian reef mass extinction Guizhou Permian-Triassic boundary

Microbialite of anoxic condition from Permian-Triassic transition in Guizhou,china

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Microbialite of anoxic condition from Permian-Triassic trans...

中国科学院地质与地球物理研究所2007学术年会

作者： WU YaSheng~(1+),JIANG HongXia~1,YANG Wan~2 & FAN JiaSong~1 1 institute of geology and Geophysics,chinese academy of sciences,Beijing 100029,china 2 Department of geology,Wichita state University,1845 Fairmount,Wichita,KS 67260,USA

Spherical microfossils are present in the Hindeodus parvus zone of the Lower Triassic in Ziyun, Guizhou *** generally range from 0.15 to 0.30 mm across,with micritic wall and filled by micro-sparry calcites,and are evenly scattered in micritic *** abundance makes the rock assigned to *** accompanied organisms include ostracods and algal mat,but no gastropods or *** of small( china by Lehrmann(1999),(3) dendroidal limestone such as that described from the vicinity of Chongqing by Kershaw et al.(1999),(4) spherical microbial limestone adapted to anoxic environments described from Ziyun,Guizhou reported in this paper,(5) limestone with cyanobacterial fossils such as that described by Wang et al.(2005),and(6) *** these microbialites are not reefs in the proper sense, and the argument that Permian reef ecosystems extended into the Mesozoic is incorrect.

关键词： Microbialites reefs Permian-Triassic boundary mass extinction end-Permian

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川西坳陷须二段层序地层特征及储层预测

天然气工业 2004年第11期24卷 45-48,15页

作者：叶泰然郑荣才中国石化西南分公司物探研究院 "油气藏地质及开发工程"国家重点实验室.成都理工大学

川西坳陷须家河组二段埋深4000-6000 m,属三角洲沉积体系,地层等时异相沉积特征突出。由于勘探程度较低,导致前期研究常出现"砂对砂、泥对泥"的地层穿时对比的情况,地层对比及储层预测难度均较大。文章运用地震地层学与高分辨率层序地... 详细信息

川西坳陷须家河组二段埋深4000-6000 m,属三角洲沉积体系,地层等时异相沉积特征突出。由于勘探程度较低,导致前期研究常出现"砂对砂、泥对泥"的地层穿时对比的情况,地层对比及储层预测难度均较大。文章运用地震地层学与高分辨率层序地层学理论,在钻井岩心、测井资料和地震信息紧密结合的基础上,实现须家河组二段大区域的等时异相地层对比,建立了地震层序约束的等时层序地层格架,剖析了其纵横向高分辨率层序地层特征,分析了地震属性与储层纵横向变化的之间关系,最终运用地震属性分析技术实现了储层横向展布预测。该研究成果经钻井验证,取得了较好的应用效果,形成了较有针对性的方法技术思路。

关键词：储层预测地层对比川西坳陷须家河组高分辨率层序地层学横向地震地层学等时钻井岩心

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