| 1 | New Findings of Latest Early Olenekian(Early Triassic)Fossils in South Primorye,Russian Far East,and Their Stratigraphical Significance显示文摘Information on latest early Olenekian(latest Smithian)ammonoids is available apparently from only seven regions of the world,including South Primorye.Latest Smithian evidences on this topic are recorded from the West SMID(abbreviation from the Russian name of the quarry:'Building Materials and Details'),East SMID and Golyj Cape areas in South Primorye.This provides additional information on systematic composition of latest Smithian ammonoid,as well as conodont and brachiopod assemblages from the recently identified Shimanskyites shimanskyi Zone,located between lower Olenekian Anasibirites nevolini Zone and upper Olenekian Tirolites subcassianus Zone.There are many common ammonoid species in the Shimanskyites shimanskyi Zone and the underlying Anasibirites nevolini Zone,e.g.,Prosphingitoides sp.,Arctoceras septentrionale(Diener),Churkites syskoi Zakharov et Shigeta,Submeekoceras?subhhydaspis(Kiparisova),Prionites markevichi Zakharov et Smyshlyaeva,?Anasibirites?simanenkoi Zakharov et Smyshlyaeva,Xenoceltites?subvariocostatus Zakharov et Smyshlyaeva,and Mianwaliites zimini Zakharov et Smyshlyaeva.The base of the Shimanskyites shimanskyi Zone,marked by a negativeδ13Corg excursion in the Kamenushka-2 Section by our previous study,coincides with the FO(first occurrence)of ammonoids Shimanskyites shimanskyi Zakharov et Smyshlyaeva and Glyptophiceras cf.sinuatum(Waagen)and conodont Hindeodella budurovi Buryi.This zone is characterized additionally by some fossils common for the overlying upper Olenekian Tirolites subcassianus Zone:ammonoids of the genus Kamenushkaites,brachiopods Bittnerihyris margaritovi(Bittner)and Lepismatina sp.and conodont?Neogondolella?(=?Borinella)jubata Sweet.The latest Smithian ammonoids recorded from the Shimanskyites shimanskyi Zone totally consist of 30 taxa belonging to 11 families(Sageceratidae,Ussuiriidae,Aspenitidae,Paranannitidae,Arctoceratidae,Proptychitidae,?Galfetitidae,Prionitidae,?Kashmiritidae,Xenoceltitidae and Palaeophyllitidae).The problems of global correlation of uppermost Smithian strata are also discussed. | Yuri D.Zakharov Liana G.Bondarenko Alexander M.Popov Olga P.Smyshlyaeva | 2021 | Journal of Earth Science2021，32，3： | 2 |
| 2 | Great Paleozoic-Mesozoic Biotic Turnings and Paleontological Education in China: A Tribute to the Achievements of Professor Zunyi Yang显示文摘Professor Zunyi Yang is a pioneer paleontologist who established the earliest Paleontological education and research in China, and has contributed his lifetime to promotion of Chinese paleontological education and researches as well as the studies on the Permian-Triassic(P-Tr) mass extinction and its possible causes. Yang has studied six fossil clades and trace fossils, together with his colleagues, he has established 6 new species of cephalopods, 1 new genus and 15 new species of gastropods, 8 new genera and 31 new species of bivalves, 17 new genera and 66 new species of brachiopods, 1 new genus and 4 new species of ophiuroids, 2 new genera and 7 new species of triopsids(Crustacea), and 3 new ichnogenera and 7 new ichnospecies of trace fossils. Yang led the 2 nd IGCP working on the P-Tr mass extinction in the world. His group's excellent works on basic stratigraphy and paleontology enable the GSSP of P-Tr boundary(PTB) to be ratified in China. Yang's earlier works on three-episode extinction pattern and volcanism-causing extinction hypothesis are also highlighted here to show how their first-hand data and initiative hypothesis have influenced the current and ongoing debates on the P-Tr crisis and possible causation. Yang school's extinction pattern is reviewed here, and their 2 nd phase of extinction is marked by a dramatic loss in biodiversity, pointing to a widely accepted mass extinction. The 3 rd extinction is characterized by ecological collapse of ecosystem structures and disappearance of the PTB microbialite ecosystem, while the 1 st extinction(also prelude extinction) is indicated by the collapses of deep-water and reef ecosystems. Updated studies show that the volcanic ashes near the PTB originated from silicic, subduction-related igneous activity with little or no basaltic input. This subduction zone activity is related to closure of the Paleo-Tethys Ocean, and the intensity and frequency of the volcanic activity appear to increase near the P-Tr extinction interval. Hg anomalies(Hg/TOC ratios and Hg isotopes) were also detected from the P-Tr extinction interval, and they are interpreted as the results of enhanced volcanic-generated atmospheric mercury, which was injected by the violate eruption of the Siberian traps. Thus, the peak felsic volcanism is coeval with violate eruption of Siberian traps, and the coupled relationship between both types of volcanisms and biotic extinction suggests a causal relationship. | Zhong-Qiang Chen Laishi Zhao Xiangdong Wang Mao Luo Zhen Guo | 2018 | Journal of Earth Science2018，29，4： | 0 |
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