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Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,yuanlong zhao b,Jinliang Yuan c,Lu Yao b,Hong yang b a {3. of earth sciences,nanjing University,nanjing 210093.china b College of Resource and Environmental Engineering,Guizhou University(Caijiaguan Campus),Guiyang 550003.china c nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,nanjing 210008,china [a]department of earth sciences Nanjing University Nanjing 210093 China [b]College of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China [c]Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13.h pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

New macroalgal fossils of the Kaili Biota in Guizhou Province, china

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Science china earth sciences 2011年第1期54卷 93-100页

作者： WU MengYin zhao yuanlong TONG JinNan yang {3. Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China department of Political Education Guiyang College Guiyang 550005 China College of Resource and Environment Guizhou University Guiyang 550004 China Key Laboratory of Karst Environment and Geohazard Prevention of Ministry of Education Guizhou University Guiyang 550004 China

The Kaili Biota of Jianhe County, Guizhou Province is found in a Burgess Shale type of deposits, and as such it provides a key fossil record for studying biotic differentiation following the Cambrian explosion. Macroalgae represent several important groups of primary producers and yet have not been well studied. Here, we report two new forms of macroalgae from the Kaili Biota, including a new genus and species and an indeterminate genus and species. The new genus and species, Parallelphyton tipica, is a heterotrichous alga with thalli composed of a prostrate cardinal axis, and parallel bundles of erect trichomes on the axis. The bifurcation of the trichomes is somewhat similar to the living heterotrichous Fritschiella （Chlorophyta）, representing ＂architectonic differentiation＂ only known in higher plants as an adaptation to terrestri~ conditions. The indeterminate genus and species consists of an arched, thick, cylindrical major shaft and irregularly spaced, curved lateral branches attached to the major shaft and subdivided into subbranches. The characteristics of the thick and strong major shaft and the lateral branch subdivided branches are analogous to the dichotomous branching of Psilophyton in Protopteridophyta. Thus, the differentiation of the thalli in these two algal forms represents the expression of properties of some higher metaphytes, indicating that the eco- logical differentiation of the macroalgae was well underway at the time of the Kaili Biota.

关键词： Cambrian Kaili Biota macroalgae ecological differentiation Guizhou

The Discovery of a Crinoid Community in the LateTriassic Zhuganpo Formation of Guizhou Provinceand Its Geological Significance

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Acta Geologica Sinica(English Edition) 1998年第3期72卷 329-333,339页

作者： yang ruidong HAO yuanlong department of earth sciences Nanjing University Nanjing Jiangsu 210093 Guizhou University of Industry Guiyang Guizhou 550002

: Recently a rich and well—preserved crinoid community including Traumatocrinus and Encrinus has been found in the Late Triassic Zhuganpo Formation in Guanling and Xingyi, Guizhou province, china. Among the fossils Traumatocrinus is the richest, and most of it occurs as clusters, with each cluster containing 3.42 crinoid branches. Study of the stem and calyx of Traumatocrinus shows that the number of stem-joints (columnals) is equal to the total stem length × K (5.85 per cm × stem—diameter). There are about 3.6 first- and second—order columnals on the whole stem. This number seems to coincide with the number of days in a year at that time. According to the present study of the palaeoecological environment of the crinoid community, it is considered that the reproduction and preservation of the crinoid community were controlled by the Late Triassic regression and the restricted bay of an interior sea behind the S—shaped shoal zone.

关键词： crinoid palaeoecological environment Late Triassic Guizhou province

Geochemistry of the trace elements and rare-earth elements at the boundary between Cambrian Series 2 and Series 3.at Jianshan,South china:Paleoenvironmental and stratigraphic implications

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Chinese Journal Of Geochemistry 2012年第4期31卷 465-475页

作者： yang Xinglian zhao yuanlong GUO Qingjun yang Hong College of Resource and Environment Guizhou UniversityGuiyang 550003China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Center of Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

The Jianshan section in Jianhe County,Guizhou Province,is a very important auxiliary section to the candidate stratotype at the boundary between Cambrian Series 2 and Series *** four samples collected from the Jianshan section of the Kaili Formation were analyzed for the concentrations of trace element and rare-earth elements(REEs) by inductively coupled plasma mass *** trace element and REE geochemical characteristics of the Kaili Formation at the Jianshan section show that trace element composition and REE distribution patterns across the section are ***,at 44 m above the base of the Kaili Formation,most trace element contents and REEs concentrations are lower than those values observed below 44 *** 44 m,an increasing trend in the concentration of both trace elements and REEs is *** geochemical data indicate important,but subtle,changes at the 44 m *** this is,in fact,verified by work in progress,geochemical criteria can provide additional supports for defining the top surface of Cambrian Series 2,especially in sections where Oryctocephalus indicus is *** element ratios,specifically Ni/Co,V/Cr,V/(Ni+V) and Th/U as well as Ce and Eu anomalies indicate that the sedimentary environment of the Kaili Formation at the Jianshan section was oxidizing,that benthic redox conditions were less oxic,and may have been influenced by freshwater as compared to the Balang ***,the Eu anomalies observed in the Kaili Formation are similar to the negative Eu anomalies observed in post-Archean sedimentary rocks,and reveal fluctuations in oxygen content from the bottom to the top of the Kaili Formation.

关键词：稀土元素地球化学特征微量元素组成寒武系电感耦合等离子体质谱法边界古环境剖面显示地层

New Bradoriid Arthropods from the Early Cambrian Balang Formation of Eastern Guizhou, South china

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Acta Geologica Sinica(English Edition) 2010年第1期84卷 56-68页

作者： PENG Jin FENG Hongzhen FU Xiaoping zhao yuanlong YAO Lu College of earth Science and Engineering Nanjing University Nanjing Jiangsu 210093 China College of Resource and Environment Engineering Guizhou University Guiyang Guizhou 550003 China State Key Laboratory Palaeobiology and Stratigraphy （NIGP CAS） Nanjing Jiangsu 210008 China Paleontological Museum ofShenzhen Xianhu Botanical Garden Shenzhen 5180004 China.

The Early Cambrian Balang Formation is comprised of mudrock and shale, which was deposited in a shelf environment in the eastern part of Guizhou, south china. The Balang Fauna, which consists of seven phyla, occurs in the middle and upper parts of the Balang Formation. Arthropods are important constituents of the Balang Fauna and include a great number of trilobites, large bivalved arthropods, and newly-discovered well-preserved bradoriid fossils. The bradoriids present include three genera and four species ： Comptaluta inflata （Cheng, 1974） emend Hou et al., 2002; Comptaluta kailiensis sp. nov., and Alutella elongeta sp. nov, Aluta sp. This faunal assemblage in the Balang Formation is distinguished from the Tsunyiella Chang, 1964, Songlinella Yin, 1978 and Kunmingella Hou, 1956 assemblage which occurs in the Niutitang and Mingxinsi formations of the yangtze Platform in middle region of Guizhou and which is earlier than the Balang Formation in age. However, this assemblage resembles the Comptaluta Opik, 1968 assemblage from the Early Cambrian Heilinpu Formation in Wuding County, Yuanan Province and from the Ordian Stage of the Cambrian of Australia. The great abundance of Comptaluta Opik, 1968 and overall taxonomic diversity of the Comptaluta Opik, 1968 assemblage set it distinctly apart from theAlutella Kobayashi et Kato, 1951 and Aluta Hou, 1956 assemblages of the Balang Formation. Alutella Kobayashi et Kato, 1951 and Aluta Hou, 1956 also occur in the Early Cambrian Niutitang Formation of the yangtze Platform of Guizhou. Individual Bradoriids from the Balang Formation are characterized by large size （〉3.mm）. The discovery of new Bradoriid assemblages not only expands the group＇s geographical range and assemblage affinities, but also indicates that Bradoriids migrated eastward from shallow-water to deeper-water environments during the Early Cambrian, indicating that they were capable of life in deeper-water, and adaptation to a new ecological setting.

关键词： Bradoriids Balang Formation Early Cambrian Guizhou china

Kaili Biota: A Taphonomic Window on Diversification of Metazoans from the Basal Middle Cambrian: Guizhou, china

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Acta Geologica Sinica(English Edition) 2005年第6期79卷 751-765页

作者： zhao yuanlong ZHU Maoyan Loren E. BABCOCK YUAN Jinliang Ronald L. PARSLEY PENG Jin yang Xinglian WANG Yue College of Resource and Environment Engineering Guizhou University Guiyang Guizhou 550003 China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing Jiangsu 210008 China department of Geological sciences 125 South Oval Mall The Ohio State University Columbus Ohio 43210 USA department of earth and Environmental sciences Tulane University New Orleans LA 70118 USA

A Burgess Shale-type biota is, in part, characterized by a wide diversity of taxa and soft-part preservation. Each provides unique historical insights into early metazoan evolution. Among the more than 40 globally distributed biotas, the early Cambrian Chengjiang and Middle Cambrian Burgess-type biotas are the largest. The Kaili Biota, from the earliest Middle Cambrian of Guizhou, china, contains representatives of 110 metazoan genera belonging to 10 phyla. It contains many well-persevered soft-bodied specimens. This Chinese biota has become the third most taxonomically diverse Burgess Shale-type fauna. Because the Kaili Biota formed in an outer-shelf environment, its main faunal character is large numbers of eocrinoids and planktoic trilobites. The Kaili is younger than the Chengjiang Biota but older than the Canadian Burgess Shale Biota; it shares 3. genera with the Chengjiang and 3. genera with the Burgess Biota. The Kaili Biota displays a taphonomic window to the diversification and evolution of marine offshore organisms covering 5.13.million years between the Early and Middle Cambrian.

关键词： Kaili Biota Burgess Shale-type biodiversity marine organisms Taijiangian Cambrian Guizhou china

Geochemical Characteristics of Eolian Deposits in the Chengdu Plain of Sichuan Province and the Implications for Provenance

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1712-1723页

作者： TAN yuanlong QIAO Yansong zhao Zhizhong WANG Yan QI Lin FU Jianli LIU Zongxiu YAO Haitao WANG Shubing JIANG Fuchu Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Neotectonic Movement and Geohazard

In this study Chengdu Red earth （CRE） from the Chengdu Plain （CP）,Sichuan province,was analyzed for its elemental （major and trace elements） and isotopic （Sm-Nd） geochemistry and compared with Pleistocene loess and paleosol samples from the Chinese Loess Plateau （CLP） in Northern *** geochemical composition of CRE is similar to north china loess,and also resembles the average *** indicates that CRE,as loess deposits in Northern china,was derived from well-mixed sedimentary protoliths that have undergone numerous upper crustal recycling ***,obvious differences in the geochemical characteristics of CRE and the north china loess are also revealed in our *** chemically stable elements,CRE has higher Ti,Zr,Hf and lower ΣREE,Ba contents in comparison with loess samples from the *** analysis shows that CRE has higher TiO2/Al2O3.SiO2/Al2O3.Ba/Rb and lower Ce/Yb,Eu/Yb,LaN/YbN and ΣLREE/ ΣHREE *** Sm-Nd isotopic geochemistry,Sm and Nd content and the εNd（0） value in CRE are significantly higher than those in north china *** higher TiO2 content in CRE coincided with a high background concentration of Ti in the Sichuan Basin and the surrounding *** lower ΣREE and higher Sm,Nd,εNd（0） values are related to the wide distribution of basalt in the southwest Sichuan *** elemental and isotopic geochemistry of CRE indicates that eolian materials in the CP predominantly come from the Sichuan Basin and the surrounding regions,which differs from loess deposits in the CLP.

关键词： The Chengdu Plain Chengdu red earth eolian deposits geochemical characteristics provenance