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Geology and Mineral Deposits of Saraikistan (South Punjab, Koh Sulaiman Range) of Pakistan: A Tabular Review of Recently Discovered Biotas from Pakistan and Paleobiogeographic Link: Phylogeny and Hypodigm of Poripuchian Titanosaurs from Indo-Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 2023年第8期900-958,共59页
Saraikistan (South Punjab and surrounding) area of Pakistan is located in the central Pakistan. This area represents Triassic-Jurassic to Recent sedimentary marine and terrestrial strata. Most of the Mesozoic and Earl... Saraikistan (South Punjab and surrounding) area of Pakistan is located in the central Pakistan. This area represents Triassic-Jurassic to Recent sedimentary marine and terrestrial strata. Most of the Mesozoic and Early Cenozoic are represented by marine strata with rare terrestrial deposits, while the Late Cenozoic is represented by continental fluvial deposits. This area hosts significant mineral deposits and their development can play a significant role in the development of Saraikistan region and ultimately for Pakistan. The data of recently discovered biotas from Cambrian to Miocene age are tabulated for quick view. Mesozoic biotas show a prominent paleobiogeographic link with Gondwana and Cenozoic show Eurasian. Phylogeny and hypodigm of Poripuchian titanosaurs from India and Pakistan are hinted at here. 展开更多
关键词 GEOLOGY Minerals Cement Dams biota Tabular Data Paleobiogeography Saraikistan South Punjab Sulaiman Range Pakistan Titanosaurs Indo-Pakistan
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New Localities and Palaeoscolecid Worms from the Cambrian(Stage 4,Series 2)Guanshan Biota in Kunming,Yunnan,South China 被引量:4
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作者 LIU Jianni HAN Jian +5 位作者 LI Jinshu WU Yichen PENG Jie QI Nan YANG Yiyao LI Juan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期1939-1945,共7页
The Guanshan Biota from the Cambrian Stage 4 Wulongqing Formation is a typical Burgess-shale type Lagerst?tte that had witnessed the Cambrian explosion. Here we report two new localities of the Guanshan Biota, which ... The Guanshan Biota from the Cambrian Stage 4 Wulongqing Formation is a typical Burgess-shale type Lagerst?tte that had witnessed the Cambrian explosion. Here we report two new localities of the Guanshan Biota, which is located at Baimei village, south of Kunming and Xinglong village, Wuding County, Yunnan Province respectively. Both localities produce soft-body fossils and several new taxa, e.g. a new species of palaeoscolecidans (Palaeoscolex xinglongensis sp. nov.) reported herein. The comparative study of the new species with similar form not only indicates that there is a diversification of palaeoscolecid species in Guanshan Biota, but also strengthens the ties between the older Chengjiang Biota and the younger Kaili Biota (and also the coeval Burgess Shale community). Three paleoecological features, including high diversity, little disparity and richness of palaeoscolecid worms, are summarized as a case study to represent the differences between Guanshan and Chengjiang Biota. 展开更多
关键词 Guanshan biota Chengjiang biota palaeoscolecid worms Cambrian Explosion China
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使用RESRAD-BIOTA程序和ERICA程序计算某核电厂址附近水域中华鲟剂量的对比 被引量:11
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作者 李静晶 刘森林 +2 位作者 陈超峰 白晓平 付斌 《辐射防护通讯》 2009年第6期6-12,29,共8页
根据某核电厂址附近水域的部分放射性核素浓度,使用美国能源部开发的RESRAD-BIOTA程序和欧洲原子能共同体开发的ERICA程序对该水域中的中华鲟进行剂量计算,同时使用蒙特卡罗方法进行了模拟计算,并将3种方法的计算参数和结果进行对比和... 根据某核电厂址附近水域的部分放射性核素浓度,使用美国能源部开发的RESRAD-BIOTA程序和欧洲原子能共同体开发的ERICA程序对该水域中的中华鲟进行剂量计算,同时使用蒙特卡罗方法进行了模拟计算,并将3种方法的计算参数和结果进行对比和分析。结果显示,ERICA程序的计算过程更符合实际情况,对于未知要素进行保守假设,其计算结果更具参考价值。 展开更多
关键词 剂量 非人类物种 RESRAD-biota程序 ERICA程序 鱼类 中华鲟
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Chihuahuan Desert Soil Biota
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作者 Walter G. Whitford Yosef Steinberger 《Open Journal of Ecology》 2021年第9期581-595,共15页
Deserts have traditionally been considered as a low moisture system where biological activity is triggered by unpredictable rainfall in time and space. Studies on desert ecosystems functions, processes, dynamics and d... Deserts have traditionally been considered as a low moisture system where biological activity is triggered by unpredictable rainfall in time and space. Studies on desert ecosystems functions, processes, dynamics and diversity of soil biota had been found to contribute to understanding of their role in primary production and management of soil ecosystems. As belowground biota is very diverse they are playing an important role in above as well below ground essential ecosystem processes e.g. primary production, decomposition, nutrient mineralization etc. The challenge is to use the emerging knowledge of soil biota diversity in understanding basic ecosystems function. 展开更多
关键词 DESERT Soil biota Plant Cover Ecophysiological Adaptation Plant Soil biota Interaction
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Kaili Biota: A Taphonomic Window on Diversification of Metazoans from the Basal Middle Cambrian: Guizhou, China 被引量:32
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作者 ZHAO Yuanlong ZHU Maoyan +5 位作者 Loren E. BABCOCK YUAN Jinliang Ronald L. PARSLEY PENG Jin YANG Xinglian WANG Yue 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第6期751-765,共15页
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 dis... 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 30 genera with the Chengjiang and 38 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. 展开更多
关键词 Kaili biota Burgess Shale-type BIODIVERSITY marine organisms Taijiangian CAMBRIAN GUIZHOU China
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Guanling Biota: A Marker of Triassic Biotic Recovery from the end-Permian Extinction in the Ancient Guizhou Sea 被引量:11
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作者 JIANG Dayong Ryosuke MOTAN +4 位作者 LI Chun HAO Weicheng SUN Yuanlin SUN Zuoyu Lars SCHMITZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第6期729-738,共10页
After a slow recovery from the end-Permian extinction during the Early Triassic and rapid radiation in the Middle Triassic, evolution of organisms reached a new peak phase in the Late Triassic. The Guanling Biota from... After a slow recovery from the end-Permian extinction during the Early Triassic and rapid radiation in the Middle Triassic, evolution of organisms reached a new peak phase in the Late Triassic. The Guanling Biota from the Wayao Member (conodont Paragondolella polygnathiformis Zone), Falang Formation, Xinpu, Guanling County, Guizhou Province, southwestern China corresponds to this peak that marks the full recovery from the end-Permian extinction of marine ecosystems. The biota is of high diversity, containing well preserved and completely articulated skeletons of vertebrates comprising marine reptiles, fishes, and invertebrates including crinoids, ammonites, bivalves, and other fossils, and is one of the best examples of marine ecosystem records in life history. The fossil marine reptiles and crinoids are most significant in this biota, especially the marine reptiles, which provide an important link between the Triassic Pacific and Tethys, and between Triassic basal forms and the Jurassic-Cretaceous marine top predators. The most remarkable fossils are the large completely articulated ichthyosaur skeletons up to and more than 10 m, and the first recorded thalattosaurs and placodonts in China. Following our review, of the 17 named reptilian taxa the eight listed here are considered to be valid: three ichthyosaurs (Qianichthyosaurus zhoui Li, 1999; Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000, Guanlingsaurus liangae Yin in Yin et al., 2000), three thalattosaurs (Anshunsaurus huangguoshuensis Liu, 1999, Xinpusaurus suni Yin in Yin et al., 2000, Xinpusaurus kohi Jiang et al., 2004), and two placodonts (Sinocyamodus xinpuensis Li, 2000, Psephochelys polyosteoderma Li and Rieppel, 2002). Mixosaurus guanlingensis Cao in Yin et al., 2000 might be a junior synonym of Qianichthyosaurus zhoui Li, 1999, and Cymbospondylus asiaticus Li and You, 2002 and Panjiangsaurus epicharis Chen and Cheng, 2003 might be junior synonyms of Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000. It needs to re-describe the holotypes after a complete preparation for clarifying the taxonomic status of Typicusichthyosaurus tsaihuae Yu in Yin et al., 2000, Xinpusaurus bamaolinensis Cheng, 2003, Neosinosaurus hoangi (Zhou in Yin et al., 2000), Wayaosaurus geei Zhou in Yin et al., 2000, Wayaosaurus bellus Zhou in Yin et al., 2000 and Placochelys ? minutus Yin and Luo in Yin et al., 2000. 展开更多
关键词 Guanling biota marine reptiles Late Triassic CARNIAN GUIZHOU China
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Neogene Paleoseismic Events and the Shanwang Biota's Burial in the Linqu Area,Shandong Province,China 被引量:7
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作者 TIAN Hongshui A.J.(Tom) VAN LOON +5 位作者 ZHANG Zengqi ZHANG Shenhe ZHANG Banghua Lü Mingying LI Fuchang MA Xuemin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1103-1119,共17页
Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the... Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the presence of seismites with plastically deformed soft-sediment deformation structures in the Shanwang Formation, and of seismic volcanic rocks in the Yaoshan Formation which show brittle deformation. The earthquake-triggered soft-sediment deformations in the seismites include load structures, ball-and-pillow structures, flame structures, piUow-like beds, boudinage structures, slump folds, syn-depositional faults, veins of liquefied sand, and dikes of liquefied sandy lime-mud. The seismic activity is also reflected in what might be called 'brittle seismites'; these originated when, under the influence of seismic vibrations, semi-consolidated conglomerate was shattered. Moreover, volcanic activity is related to intense earthquakes that affected basalts intercalated with sand layers; these successions are known as 'seismic volcanic rocks', which are characterized by veins of liquefied sand intruding the basalts. AH above traces of paleoseismic activity were left from one single time span of 4 Ma with active seismicity that took place 14-10 Ma. This time span is known as 'the Linqu Neogene Paleoseismic Active Period', which is divided into four paleoseismic episodes, which were responses to tectonic extension and basin rifting in this area. It even includes the activity of the Yishu Fault Zone during the Miocene and the Neogene. The ratios of trace elements in the seismites, w(La)/w(Sc) and w (La)/w(Th) are higher than the average value of the upper crust, but w(Th)/w(Sc) is lower; this is geochemical evidence for the basin rifting that resulted in a high sedimentation rate. The intense and frequent paleo-earthquakes are held responsible for the rapid burial of the Shanwang Biota. Secondary earthquake-induced processes (e.g. slumping of a lake shore and the strongly increased lacustrine sedimentation rate) contributed to the rapid burial of the biota. 展开更多
关键词 Paleo-seismic event Shanwang biota rapid burial Linqu NEOGENE
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Solenites (Czekanowskiales) from the Late Mesozoic Jehol Biota of Southeastern Jilin,China and its Paleoclimatic Implications 被引量:5
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作者 LI Yunfeng SUN Chunlin +3 位作者 LI Tao NA Yuling CHEN Yuejun XING Dehe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1088-1102,共15页
Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baisha... Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baishan Basin, southeastern Jilin. The faunal remains from this formation distinctly belong to the Early Cretaceous Lycoptera-Ephemeropsis-Eosestheria assemblage of the Jehol Biota. Based on the gross leaf morphology and epidermal structures, two new species and one indeterminate species of genus Solenites (Czekanowskiales), S. baishanensis sp. nov., S. gracilis sp. nov. and S. sp. are described in this paper. This is the first fossil plant of Czekanowskiales reported from this new fossil locality of the easternmost area of the Late Mesozoic Jehol Biota, China. The new discovery contributes to improve our knowledge for understanding of leaf morphology, epidermal characters and diversity of this genus during the Early Cretaceous time, and extends geologic and geographic distribution of Solenites in northern China and Eurasia. Along with consideration of associated plant and faunal assemblages and sedimentology, we suggest that the regional climate was warm and moderately humid with seasonal temperature and precipitation variations in warm-temperate zone during the Early Cretaceous. 展开更多
关键词 Solenites Early Cretaceous Jehol biota southeastern Jilin China
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First report on Guanshan Biota(Cambrian Stage 4) at the stratotype area of Wulongqing Formation in Malong County, Eastern Yunnan, China 被引量:4
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作者 Feiyang Chen Zhifei Zhang +2 位作者 Marissa J. Betts Zhiliang Zhang Fan Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1459-1476,共18页
Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological exp... Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian explosion.Critically,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils alone.The Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and organs.To date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential buildings.Here we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype section.Fossils retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of body.In addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after weathering.This discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan. 展开更多
关键词 Guanshan biota Early CAMBRIAN Xiaojiang Fault EASTERN YUNNAN PALAEOENVIRONMENT PALAEOGEOGRAPHY
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An Updated Review of the Middle-Late Jurassic Yanliao Biota: Chronology,Taphonomy,Paleontology and Paleoecology 被引量:5
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作者 XU Xing ZHOU Zhonghe +2 位作者 Corwin SULLIVAN WANG Yuan REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2229-2243,共15页
The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning,... The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning, northern Hebei, and southeastern Inner Mongolia. The biota lasted for about 10 million years, divided into two phases: the Bathonian-Callovian Daohugou phase (about 168-164 million years ago) and the Oxfordian Linglongta phase (164-159 million years ago). The Yanliao fossils are often taphonomically exceptional (many vertebrate skeletons, for example, are complete and accompanied by preserved integumentary features), and not only are taxonomically diverse but also include the oldest known representatives of many groups of plants, invertebrates, and vertebrates. These fossils have provided significant new information regarding the origins and early evolution of such clades as fleas, birds, and mammals, in addition to the evolution of some major biological structures such as feathers, and have demonstrated the existence of a complex terrestrial ecosystem in northeast China around the time of the Middle-Late Jurassic boundary. 展开更多
关键词 Yanliao biota Daohugou phase Linglongta phase Middle-Late Jurassic Yanliao area
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New Macroscopic Problematic Fossil from the Early Cambrian Yanjiahe Biota,Yichang,Hubei,China 被引量:5
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作者 GUO Junfeng LI Yong +3 位作者 HAN Huiping OU Qiang ZHOU Jianren ZHENG Yajuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期791-798,共8页
Yanjiahella gen. nov., a distinctive fossil taxon from the Early Cambrian Yanjiahe Biota in Yichang, Hubei Province, is characterized by: 1) an overall body plan composed of a stalk and a calyx (also arms in some s... Yanjiahella gen. nov., a distinctive fossil taxon from the Early Cambrian Yanjiahe Biota in Yichang, Hubei Province, is characterized by: 1) an overall body plan composed of a stalk and a calyx (also arms in some species); 2) a stalk with closely spaced, transverse wrinkles and a medial, longitudinal ridge; and 3) a calyx preserved with three-dimensional radiating striations, as well as a probable madreporite in some specimens. Three species that can be assigned to this genus, which are Y. ancarpa sp. nov., Y. monocarpa sp. nov., and Y. biscarpa sp. nov. Yanjiahella is comparable to certain echinoderm taxa in terms of morphology and some biological structures, which might indicate the early evolution and diversification of ancestral echinoderm lineages from the early Early Cambrian Yangtze Platform. The discovery of putative echinoderms in the Yanjiahe Biota provides significant clues about the origination and evolution of the deuterostome phylum Echinodermata. 展开更多
关键词 Yanjiahella echinoderm-like organisms Terreneuvian Yanjiahe biota Yichang HUBEI
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Dinomischus from the Middle Cambrian Kaili Biota, Guizhou, China 被引量:4
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作者 PENG Jin ZHAO Yuanlong LIN Jih-Pai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期498-501,共4页
Dinomischus is a rare solitary epifaunal suspension feeder. The over-all morphology of Dinomischus consists of a conical calyx surrounded with elongate bracts and an elongate stem. Visceral mass and stomach sac are ev... Dinomischus is a rare solitary epifaunal suspension feeder. The over-all morphology of Dinomischus consists of a conical calyx surrounded with elongate bracts and an elongate stem. Visceral mass and stomach sac are evident in the body cavity. Dinomischus is interpreted as a primative ancestor of living entoprocts based on similarities in morphology and mode of life. Previously, Dinomischus is only known in two localities: the mid-Middle Cambrian Burgess Shale Biota and the Early Cambrian Chengjiang Biota. A single specimen of Dinomischus cf. D. isolatus Cowry Morris, 1977 from the Kaili Biota, Guizhou, China is reported here. The discovery of Dinomischus in the Kaili Biota extends its geographical range and indicated that the rare Dinomischus could tolerate deeper water settings during the Middle Cambrian. 展开更多
关键词 Dinomischus Kaili biota Middle Cambrian GUIZHOU China
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New Bivalved Arthropods from Mid-Cambrian Kaili Biota of Southeastern Guizhou,Southwest China 被引量:3
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作者 YUAN Jinliang PENG Jin ZHAO Yuanlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第4期758-764,共7页
Bivalved arthropods are very important elements in Mid-Cambrian Kaili Biota.Three genera,Alicaris,Pseudoarctolepis,and Forfexicaris,are herein recorded for the first time,including three new species:Alicaris kailiens... Bivalved arthropods are very important elements in Mid-Cambrian Kaili Biota.Three genera,Alicaris,Pseudoarctolepis,and Forfexicaris,are herein recorded for the first time,including three new species:Alicaris kailiensis sp.nov.,Forfexicaris reticulata sp.nov.,and Pseudoarctolepis semicircularis sp.nov.,of which Alicaris kailiensis sp.nov.could be assigned to crustaceomorphs;the other two forms are grouped as proschizoramians.These forms provide important information about the distribution and species diversity of a poorly-known element of Cambrian fauna,and also bridge the biotic evolutionary gap between Early Cambrian Chengjiang Biota in Southwest China and Mid-Cambrian burgess shale biota in North America. 展开更多
关键词 Alicaris Pseudoarctolepis Forfexicaris Kaili biota Mid-Cambrian GUIZHOU
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New Fossil Beetles of the Family Ommatidae (Coleoptera: Archostemata) from the Jehol Biota of China 被引量:3
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作者 TAN Jingjing REN Dong +1 位作者 SHIH Chungkun GE Siqin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期474-485,共12页
A new genus with one new species and five new species of genus Amblomma of fossil ommatids are described and illustrated: Euryomma tylodes gen. et sp. nov., Amblomma cyclodonta sp. nov., Amblomma miniscula sp. nov., ... A new genus with one new species and five new species of genus Amblomma of fossil ommatids are described and illustrated: Euryomma tylodes gen. et sp. nov., Amblomma cyclodonta sp. nov., Amblomma miniscula sp. nov., Amblomma porrecta sp. nov., Amblomma eumeura sp. nov., and Amblomma protensa sp. nov. All of them were collected from the Upper Jurassic or Lower Cretaceous Yixian Formation of western Liaoning, China. A key to the species of Amblomma is given. The wide epipleural space shows that Euryomma may be a primitive genus in Ommatidae. Many different species of Amblomma occurred within the same sedimentary horizon in this area could be environmental changes caused by frequent volcanic activities during the deposition of the Yixian Formation. 展开更多
关键词 Ommatidae Jehol biota Late Jurassic Early Cretaceous Yixian Formation LIAONING
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RESRAD-BIOTA程序的改进及其应用研究 被引量:6
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作者 白晓平 《科技导报》 CAS CSCD 北大核心 2009年第12期61-64,共4页
目前,电离辐射对生物产生的影响开始受到越来越多的关注,对生物辐射效应进行评价首先要估算生物所受到的辐射剂量率。RESRAD-BIOTA程序基于美国能源部(USDOE)技术标准DOE-STD-1153-2002中的分级(graded)方法,可以计算环境中生物受到的... 目前,电离辐射对生物产生的影响开始受到越来越多的关注,对生物辐射效应进行评价首先要估算生物所受到的辐射剂量率。RESRAD-BIOTA程序基于美国能源部(USDOE)技术标准DOE-STD-1153-2002中的分级(graded)方法,可以计算环境中生物受到的辐射剂量率。针对该程序的不足之处对其进行了改进,将改进后的程序用于中国某滨海核电厂厂址附近水生生物辐射剂量率的评估中,并对程序的应用进行了初步研究,最后讨论了程序应用中需要注意的问题。 展开更多
关键词 RESRAD-biota程序 生物 辐射影响 辐射剂量率
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Guanling Biota: A Rare Biota in Sea Early Late Triassic 被引量:3
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作者 Wang Shangyan The State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 Guizhou Geological Survey, Guiyang, 550004 Wang Yangeng Wang Liting Yin Gongzheng Guizhou Geological Survey, Guiyang 550004 《Journal of China University of Geosciences》 SCIE CSCD 2002年第3期215-216,共2页
Guanling biota has been found at the bottom of Wayao Formation of Upper Triassic (Carnic stage) near Xinpu town, Guanling County, Guizhou Province, China. There are a lot of crinoids and marine reptiles, which is a ch... Guanling biota has been found at the bottom of Wayao Formation of Upper Triassic (Carnic stage) near Xinpu town, Guanling County, Guizhou Province, China. There are a lot of crinoids and marine reptiles, which is a characteristic of Guanling biota, including ammonites, bivalve, brachiopod, fish, conodont and plant. These fossils are featured not only with the large quantity, but also with their extraordinary perfect forms. This paper explores the meaning, geological background, present situation of study and scientific significance of Guanling biota. 展开更多
关键词 Guanling biota TRIASSIC Guizhou.
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RESRAD-BIOTA和ERICA程序对滨海核电厂浅水鱼的辐射剂量估算比较研究 被引量:18
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作者 白晓平 杜红燕 郑伟 《辐射防护》 CAS CSCD 北大核心 2011年第2期65-71,共7页
RESRAD-BIOTA和ERICA程序是国际上目前比较成熟的两个非人类物种辐射效应评估程序。从参考生物的定义、筛选方法、计算原理等方面对两个程序进行了比较和分析,并利用两个程序分别对我国某滨海核电厂液态放射性流出物对厂址附近一类浅水... RESRAD-BIOTA和ERICA程序是国际上目前比较成熟的两个非人类物种辐射效应评估程序。从参考生物的定义、筛选方法、计算原理等方面对两个程序进行了比较和分析,并利用两个程序分别对我国某滨海核电厂液态放射性流出物对厂址附近一类浅水鱼所产生的辐射影响进行评估,最后对比分析了两个程序的计算结果和优缺点。 展开更多
关键词 RESRAD-biota程序 ERICA程序 非人类物种 辐射效应评估
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Carbon Isotopic Evolution of the Late Ediacaran Gaojiashan Biota on the Northern Yangtze Platform,South China 被引量:2
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作者 GUO Qingjun DENG Yinan YANG Xinglian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1447-1454,共8页
Metazoan fossils in the Gaojiashan Biota are famous for being well preserved and may provide new insights into the early evolution and skeletonization of Metazoans. We are studying the isotopic compositions of organic... Metazoan fossils in the Gaojiashan Biota are famous for being well preserved and may provide new insights into the early evolution and skeletonization of Metazoans. We are studying the isotopic compositions of organic and carbonate carbon from a sequence of sedimentary rocks at the Gaojiashan section, northern Yangtze Platform, Shaanxi Province of China. Organic carbon isotope values display a range between -30.8%0 and -24.7%0 with clear stratigraphic variations. Carbonate carbon isotope data vary between 0.1%o and +6%0. Positive j13C values from sediments with Gaojiashan biota reflect temporal variations in carbon turnover, i.e. an increasing in photosynthetic carbon fixation followed by an increasing subsequent fractional organic carbon burial, and that related to bio- radiation such as increasing algae, bacteria, and original creatures productivity in biomass. These secular variations are interpreted to reflect perturbations of the regional carbon cycle, specifically changes in the fractional burial of organic carbon, and discuss the relationship between Gaojiashan biota and paleoenvrionmental variation. 展开更多
关键词 EDIACARAN carbonate and organic carbon isotopic composition Gaojiashan biota Ningqiang Yangtze Platform
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Dimorphism of Bivalved Arthropod Branchiocaris? Yunnanensis from the Early Cambrian Chengjiang Biota, South China 被引量:1
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作者 WU Yu FU Dongjing +2 位作者 ZHANG Xingliang Allison C. DALEY SHU Degan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期818-826,共9页
The bivalved arthropod Branchiocaris? yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The car... The bivalved arthropod Branchiocaris? yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The carapace comprises two identical valves, each valve are sub-circular in outline, ranging from 24 mm to 58 mm in length, and from 15 mm to 46 mm in height. The dorsal margin is straight and bears two short cardinal spines. The valve surface is either smooth or ornamented with polygonal reticular structures, which may result from different preservation conditions. Two morphotypes have been recognized based on the presence or absence of a subdorsal swelling of the valve, which is convex dorsolaterally and extends beyond the dorsal margin when it appears. Statistic and ontogenetic analyses show both morphotypes grow isometrically and have the same growth trajectory. Therefore, the two morphotypes are interpreted as dimorphism within the same species. Our results are helpful for investigating the taxonomy and ontogeny of arthropod fossils and suggest that dimorphism might be fairly common in these early arthropods. 展开更多
关键词 ARTHROPODA Branchiocaris DIMORPHISM ONTOGENY Chengjiang biota
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A Mesozoic Pompeii: History of the Jehol Biota's Rise and Fall 被引量:1
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作者 SHAO Tiequan ZHANG Hu +2 位作者 WANG Qi LIU Yunhuan ZHANG Yanan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1893-1903,共11页
The Jehol fauna was initially represented by a bony fish, concostracan and an insect, as a Lycoptera davidi-Eosestheria-Ephemeropsis trisetalis association,but since the researches of recent decades, the Jehol Biota i... The Jehol fauna was initially represented by a bony fish, concostracan and an insect, as a Lycoptera davidi-Eosestheria-Ephemeropsis trisetalis association,but since the researches of recent decades, the Jehol Biota is now completely different from the past low-diversity, and encompasses a native terrestrial biota that includes many well-preserved vertebrates, invertebrates and plants. There are more than 20 important biological categories, thousands of taphonomically unusual fossils, especially noted for the wide variety of biological tissues. The Jehol Biota has caused a sensation in the world with its wide distribution, large quantity, great variety, fine preservation and detailed information, which records the rise and fall of the numerous taxa, and provides significant evidence for three origins: of birds, eutherian mammals, and angiosperms. The Jehol Biota is a highlight of basic scientific research in China, and we honor it as a world-class fossil treasury and "a Mesozoic Pompeii". 展开更多
关键词 GEOHERITAGE PALEONTOLOGY Jehol biota evolutionary origins JURASSIC-CRETACEOUS NortheastAsian region Liaoning province
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