This study recovered the Guadalupian conodont faunas from Shangsi （上寺） Section in Northeast Sichuan （四川）. Four genera and nine species were identified, and three conodont zones were recognized and established;...This study recovered the Guadalupian conodont faunas from Shangsi （上寺） Section in Northeast Sichuan （四川）. Four genera and nine species were identified, and three conodont zones were recognized and established; they include Jinogondolella nankingensis Zone, J. aserrata Zone, and J. postserrata Zone. The Roadian and Wordian boundary is set in the interval 5 m from the top of Bed 86 by the first appearance of the conodont J. aserrata. The Wordian and Capitanian boundary is set in the interval 2.3 m from the top of the Bed 95 by the first appearance ofJ. postserrata. Most of the specimens demonstrated low color alteration index （CAI） as 1.5-3, indicating that most part of the Maokou （茅口） Formation may have the suitable thermal conditions for the formation of oil source rocks.展开更多
On the basis of establishment of radiolarian biostratigraphy and conodont biostratigraphy, a radiolarian Albaillella fauna in the transitional environment from Guadalupian to Lopingian Series in Permian was found at a...On the basis of establishment of radiolarian biostratigraphy and conodont biostratigraphy, a radiolarian Albaillella fauna in the transitional environment from Guadalupian to Lopingian Series in Permian was found at a pelagic chert section in southeast Guangxi, South China. Radiolarian Albaillella is one of the most sensitive biology to the transitional environment. The Albaillella fauna shows an ecological evolutionary process from Guadalupian to Lopingian: declined stage-recovery stage-flourishing stage. The study of characteristics of the Albaillella fauna in the transitional environment may provide more information, not only for the subdivision and correlation of a high-resolution biostratigraphy, but also for influence of radiolarian Albaillella fauna on the pre-Lopingian mass extinction.展开更多
Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, con...Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, conifers, vojnovskyans) represented by stems, leaves and reproductive organs;invertebrates(mollusks, arthropods), and tetrapods(temnospondyl amphibians, seymouriamorphs, cotylosaurs, synapsids, diapsids), as well as bony fishes. General characteristics of the taxonomical composition of the Kuedinskie Kluchiki locality are given. A new peltaspermalean pteridosperm taxon, Compsopteris longipinnata sp. nov., and a voltzialean conifer Archaeovoltzia kuedensis sp. nov. are described. General considerations on the paleoecologic and paleogeographic conditions of the Kuedinskie Kluchiki locality origin are given.展开更多
A mixed siliciclastic-carbonate system that responds to changes in Permian climate and subsequent carbonate platform evolution is investigated using microscopic details of the Middle Permian Amb Formation(Fm.),in Saiy...A mixed siliciclastic-carbonate system that responds to changes in Permian climate and subsequent carbonate platform evolution is investigated using microscopic details of the Middle Permian Amb Formation(Fm.),in Saiyiduwali section,Khisor Range,northern Pakistan.Thin sections were made from rocks throughout the stratigraphic section of the Amb Fm.and analyzed with an emphasis on carbonate and clastic microfacies,and the latter interpreted within the existing chronostratigraphic framework.Outcrop observations reveal that the units comprise coarse-grained,channelized,ripplemarked,and burrowed sandstone and sandy,fossiliferous limestone with minor marls and shale intercalations,suggesting deposition in a subaqueous tide-dominated delta to beach barrier.Based on the determined seven microfacies coupled with outcrop observation,the Amb Fm.was deposited in a tide-influenced subaqueous delta to middle shelf environment under fluctuating sea level.The deposition of compositionally mature sandstone in the lower part of the formation suggests reworking of detritus from the rift shoulders and an adjacent source area with an ambient warm and humid climate.The stratal mixing of carbonates and compositionally mature siliciclastic units in the middle part suggest deposition under tectonic and climate-induced terrigenous and carbonate fluxes to the basin.Thus the deposition shows a perfect transition from clastic-dominated deltaic to pure carbonate platform settings as a result of warm climate and tectonics.This Middle Permian warming is confirmed by sea-level rise and the presence of a temperature-sensitive fusulinid fauna in association with photozoan-based ooids.Deposition of the Amb Fm.and establishment of a carbonate platform are envisaged to be associated with major rifting of northern Gondwana,which subsequently resulted in the development of a rift basin at the passive margin of the NW Indian Plate then in northern Pakistan.展开更多
基金supported by the SINOPEC project (G0800-06-ZS-319)the National Natural Science Foundation of China (No. 40621002)+1 种基金the Program for Changjiang Scholars and Innovative Research Team (IRT0546)the "111" Project (No. B08030)
文摘This study recovered the Guadalupian conodont faunas from Shangsi （上寺） Section in Northeast Sichuan （四川）. Four genera and nine species were identified, and three conodont zones were recognized and established; they include Jinogondolella nankingensis Zone, J. aserrata Zone, and J. postserrata Zone. The Roadian and Wordian boundary is set in the interval 5 m from the top of Bed 86 by the first appearance of the conodont J. aserrata. The Wordian and Capitanian boundary is set in the interval 2.3 m from the top of the Bed 95 by the first appearance ofJ. postserrata. Most of the specimens demonstrated low color alteration index （CAI） as 1.5-3, indicating that most part of the Maokou （茅口） Formation may have the suitable thermal conditions for the formation of oil source rocks.
文摘On the basis of establishment of radiolarian biostratigraphy and conodont biostratigraphy, a radiolarian Albaillella fauna in the transitional environment from Guadalupian to Lopingian Series in Permian was found at a pelagic chert section in southeast Guangxi, South China. Radiolarian Albaillella is one of the most sensitive biology to the transitional environment. The Albaillella fauna shows an ecological evolutionary process from Guadalupian to Lopingian: declined stage-recovery stage-flourishing stage. The study of characteristics of the Albaillella fauna in the transitional environment may provide more information, not only for the subdivision and correlation of a high-resolution biostratigraphy, but also for influence of radiolarian Albaillella fauna on the pre-Lopingian mass extinction.
文摘Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, conifers, vojnovskyans) represented by stems, leaves and reproductive organs;invertebrates(mollusks, arthropods), and tetrapods(temnospondyl amphibians, seymouriamorphs, cotylosaurs, synapsids, diapsids), as well as bony fishes. General characteristics of the taxonomical composition of the Kuedinskie Kluchiki locality are given. A new peltaspermalean pteridosperm taxon, Compsopteris longipinnata sp. nov., and a voltzialean conifer Archaeovoltzia kuedensis sp. nov. are described. General considerations on the paleoecologic and paleogeographic conditions of the Kuedinskie Kluchiki locality origin are given.
基金supported by the National Natural Science Foundation of China(NSFC Grant Nos.41272115,41572086)。
文摘A mixed siliciclastic-carbonate system that responds to changes in Permian climate and subsequent carbonate platform evolution is investigated using microscopic details of the Middle Permian Amb Formation(Fm.),in Saiyiduwali section,Khisor Range,northern Pakistan.Thin sections were made from rocks throughout the stratigraphic section of the Amb Fm.and analyzed with an emphasis on carbonate and clastic microfacies,and the latter interpreted within the existing chronostratigraphic framework.Outcrop observations reveal that the units comprise coarse-grained,channelized,ripplemarked,and burrowed sandstone and sandy,fossiliferous limestone with minor marls and shale intercalations,suggesting deposition in a subaqueous tide-dominated delta to beach barrier.Based on the determined seven microfacies coupled with outcrop observation,the Amb Fm.was deposited in a tide-influenced subaqueous delta to middle shelf environment under fluctuating sea level.The deposition of compositionally mature sandstone in the lower part of the formation suggests reworking of detritus from the rift shoulders and an adjacent source area with an ambient warm and humid climate.The stratal mixing of carbonates and compositionally mature siliciclastic units in the middle part suggest deposition under tectonic and climate-induced terrigenous and carbonate fluxes to the basin.Thus the deposition shows a perfect transition from clastic-dominated deltaic to pure carbonate platform settings as a result of warm climate and tectonics.This Middle Permian warming is confirmed by sea-level rise and the presence of a temperature-sensitive fusulinid fauna in association with photozoan-based ooids.Deposition of the Amb Fm.and establishment of a carbonate platform are envisaged to be associated with major rifting of northern Gondwana,which subsequently resulted in the development of a rift basin at the passive margin of the NW Indian Plate then in northern Pakistan.
