Conodonts and ammonoids have played significant roles in the Permian-Triassic time- scale. In order to uncover the nature of the Permian-Triassic mass extinction and subsequent recovery, we studied conodont and ammono...Conodonts and ammonoids have played significant roles in the Permian-Triassic time- scale. In order to uncover the nature of the Permian-Triassic mass extinction and subsequent recovery, we studied conodont and ammonoid biostratigraphies around the Permian-Triassic boundary from Jianzishan of Hubei, South China. A total of four conodont zones and two ammonoid beds are recog- nized. In ascending order, the conodont zones are Late Changhsingian Clarkina changxingensis Zone, Clarkina yini Zone and Griesbachian Hindeodus parvus Zone, Hindeodus postparvus Zone; the ammon- oid beds are Late Griesbachian Ophiceras beds and Early Dienerian Ussuridiscus varaha beds. At Jian- zishan, Ophiceras beds are stratigraphically younger than Hindeodus parvus Zone, but it is likely to be the same level with Hindeoduspostparvus Zone. The Lower Dienerian in Bed 8 in this section is charac- terized by ammonoid Ussuridiscus varaha beds, which is associated with many Late Grieshachian cono- donts including Hindeodus postparvus, Hindeodus praeparvus, Hindeodus typicalis, Hindeodus pisai, Hindeodus latidentatus, Hindeodus parvus, Hindeodus anterodentatus and Isarcicella turgida, indicating these conodont species could pass through the Griesbachian-Dienerian boundary and occurred in the Early Dienerian oceans.展开更多
After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in reco...After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.展开更多
This work reports a synthesis of biostratigraphic outputs resulting from over two decades of comprehensive analysis on the expressive stratigraphic record of the Aalenian of the Lusitanian Basin(Western Iberian Margin...This work reports a synthesis of biostratigraphic outputs resulting from over two decades of comprehensive analysis on the expressive stratigraphic record of the Aalenian of the Lusitanian Basin(Western Iberian Margin;Portugal).The rich and diverse ammonite record studied from ten marly and marlylimestones sections,outcropping in different sectors of the basin ranging from distal to proximal facies,has enabled the establishment of a detailed ammonite-based biostratigraphical framework correlated with other basins located around the Iberian Plate.The study of the benthic foraminiferal assemblages occurring in the basin at the same time interval has allowed the establishment of a biostratigraphic scale based on microfossils accurately calibrated with the ammonite record,an important tool in log interpretation in the context of hydrocarbon exploration activities in sedimentary basins of Jurassic age.展开更多
To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the b...To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova） （dominant）, Megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.展开更多
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 ...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.展开更多
An exceptionally large specimen of Permian ammonoid genus Shengoceras is reproted from Guangxi, South China. The giant size and the matured stage of the suture extend the definition of this genus and its subfamily in ...An exceptionally large specimen of Permian ammonoid genus Shengoceras is reproted from Guangxi, South China. The giant size and the matured stage of the suture extend the definition of this genus and its subfamily in taxonomy of Permian cyclolobids.展开更多
基金supported by the State Key R&D Project of China(No.2016YFA0601100)the National Natural Science Foundation of China(Nos.41622207,41302271,41530104)the 111 Project(No.B08030)
文摘Conodonts and ammonoids have played significant roles in the Permian-Triassic time- scale. In order to uncover the nature of the Permian-Triassic mass extinction and subsequent recovery, we studied conodont and ammonoid biostratigraphies around the Permian-Triassic boundary from Jianzishan of Hubei, South China. A total of four conodont zones and two ammonoid beds are recog- nized. In ascending order, the conodont zones are Late Changhsingian Clarkina changxingensis Zone, Clarkina yini Zone and Griesbachian Hindeodus parvus Zone, Hindeodus postparvus Zone; the ammon- oid beds are Late Griesbachian Ophiceras beds and Early Dienerian Ussuridiscus varaha beds. At Jian- zishan, Ophiceras beds are stratigraphically younger than Hindeodus parvus Zone, but it is likely to be the same level with Hindeoduspostparvus Zone. The Lower Dienerian in Bed 8 in this section is charac- terized by ammonoid Ussuridiscus varaha beds, which is associated with many Late Grieshachian cono- donts including Hindeodus postparvus, Hindeodus praeparvus, Hindeodus typicalis, Hindeodus pisai, Hindeodus latidentatus, Hindeodus parvus, Hindeodus anterodentatus and Isarcicella turgida, indicating these conodont species could pass through the Griesbachian-Dienerian boundary and occurred in the Early Dienerian oceans.
基金supported by the Russian grant RFBR(No.14-05-00011-a)
文摘After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.
基金supported by FEDER funds through the Competitiveness Factors Operational Programme-COMPETE and national funds by FCT in the frame of the UID/Multi00073/2013 projectThe study is a contribution for the Projects CGL2011-23947 and CGL2011-25894(Ministerio de Ciencia e Innovación,Spain)+1 种基金for the Grupo de Investigación UCM 910431(Complutense University,Madrid,Spain).supported by the Consórcio Petrobras-Galp-Partex of Portugal.
文摘This work reports a synthesis of biostratigraphic outputs resulting from over two decades of comprehensive analysis on the expressive stratigraphic record of the Aalenian of the Lusitanian Basin(Western Iberian Margin;Portugal).The rich and diverse ammonite record studied from ten marly and marlylimestones sections,outcropping in different sectors of the basin ranging from distal to proximal facies,has enabled the establishment of a detailed ammonite-based biostratigraphical framework correlated with other basins located around the Iberian Plate.The study of the benthic foraminiferal assemblages occurring in the basin at the same time interval has allowed the establishment of a biostratigraphic scale based on microfossils accurately calibrated with the ammonite record,an important tool in log interpretation in the context of hydrocarbon exploration activities in sedimentary basins of Jurassic age.
文摘To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova） （dominant）, Megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.
基金the financial support of Russian FBR(No.18-05-00023A)。
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.
文摘An exceptionally large specimen of Permian ammonoid genus Shengoceras is reproted from Guangxi, South China. The giant size and the matured stage of the suture extend the definition of this genus and its subfamily in taxonomy of Permian cyclolobids.
