Review of the literature on Ordovician conodont diversification in palaeoplates of North and Western China reveals that four diversity peaks are present in North China,occurring in the middle Tremadocian,early Floian,...Review of the literature on Ordovician conodont diversification in palaeoplates of North and Western China reveals that four diversity peaks are present in North China,occurring in the middle Tremadocian,early Floian,late Floian,and late Darriwilian,with three of these peaks(excepting that in the late Floian)also being recorded in Tarim.Three diversification intervals are present in North China,during the Tremadocian,late Floian,early and middle Darriwilian;comparable intervals are observed in the early and late Tremadocian,early Floian,and the Middle Ordovician in Tarim.The main conodont diversification episode in both palaeoplates took place in the Darriwilian,at the time of the Great Ordovician Biodiversification Event.A comparison of conodont diversity patterns in different palaeoplates(North China,Tarim,and South China)demonstrates that conodont radiation events mainly occurred within the Tremadocian,Floian,and Darriwilian.Conodont diversifications in these paleoplates also display some differences.In contrasting with Tarim and South China,North China witnessed a rapid conodont diversification during late Floian time.Conodont diversity in North China and Tarim increased continually and reached a peak in the late Darriwilian,concurrent with a prominent decreasing trend in South China.Differences of conodont diversification in these three palaeoplates may be related to their palaeogeography and tectonic history.When conodont diversifications in North China and Tarim are analysed on the background of palaeoenvironments,the main episodes are seen to be partly coincident with second order sea-level changes,particularly in North China.In general,conodont radiation correlates with large scale transgressions.展开更多
Biostratigraphically constrained sequences at the Wushi Yingshan and Kalpin Cement Plant sections (Kalpin Region; Tarim Basin) were densely sampled for geochemical studies. Carbonates across the Cambrian-Ordovician bo...Biostratigraphically constrained sequences at the Wushi Yingshan and Kalpin Cement Plant sections (Kalpin Region; Tarim Basin) were densely sampled for geochemical studies. Carbonates across the Cambrian-Ordovician boundary of both sections mainly record negative carbon isotope values. Stable isotope curves show four negative and four positive excursions appearing alternately at the Wushi Yingshan section and five negative alternating with five positive excursions at the Kalpin Cement Plant section. The carbon isotope logs of these two sections are correlated with the international Cambrian-Ordovician boundary key sections: (1) Dayangcha section in China, (2) Green Point section in Canada, (3) Black mountain section in Australia and (4) Lowson Cove section in USA. These correlations suggest that the Cambrian-Ordovician boundary of the Wushi Yingshan section and the Kalpin Cement Plant section can be placed within a particular horizon that also corresponds to the observed biostratigraphic units.展开更多
首次在新疆塔里木盆地塔中地区中2井上奥陶统良里塔格组礁岩中发现保存精美的牙形刺化石,包括6属13种和未定种,含一个新亚种Belodina longxianensis minor subsp.nov.。根据牙形刺化石确定,良里塔格组上部属于上奥陶统中部的Belodina co...首次在新疆塔里木盆地塔中地区中2井上奥陶统良里塔格组礁岩中发现保存精美的牙形刺化石,包括6属13种和未定种,含一个新亚种Belodina longxianensis minor subsp.nov.。根据牙形刺化石确定,良里塔格组上部属于上奥陶统中部的Belodina confluens带。中2井良里塔格组第2—4层生物礁发育的精确时代是Belodina confluens带。展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.41202005,41221001,40825006)State Key Laboratory of Palaeobiology and Stratigraphy(Grant No.Y126110409)+1 种基金Chinese Academy of Sciences(Grant No.KZCX2-YW-Q05-01)a contribution to Project IGCP 591:The Early to Middle Paleozoic Revolution
文摘Review of the literature on Ordovician conodont diversification in palaeoplates of North and Western China reveals that four diversity peaks are present in North China,occurring in the middle Tremadocian,early Floian,late Floian,and late Darriwilian,with three of these peaks(excepting that in the late Floian)also being recorded in Tarim.Three diversification intervals are present in North China,during the Tremadocian,late Floian,early and middle Darriwilian;comparable intervals are observed in the early and late Tremadocian,early Floian,and the Middle Ordovician in Tarim.The main conodont diversification episode in both palaeoplates took place in the Darriwilian,at the time of the Great Ordovician Biodiversification Event.A comparison of conodont diversity patterns in different palaeoplates(North China,Tarim,and South China)demonstrates that conodont radiation events mainly occurred within the Tremadocian,Floian,and Darriwilian.Conodont diversifications in these paleoplates also display some differences.In contrasting with Tarim and South China,North China witnessed a rapid conodont diversification during late Floian time.Conodont diversity in North China and Tarim increased continually and reached a peak in the late Darriwilian,concurrent with a prominent decreasing trend in South China.Differences of conodont diversification in these three palaeoplates may be related to their palaeogeography and tectonic history.When conodont diversifications in North China and Tarim are analysed on the background of palaeoenvironments,the main episodes are seen to be partly coincident with second order sea-level changes,particularly in North China.In general,conodont radiation correlates with large scale transgressions.
基金the Tarim Oilfield Company, PetroChina, the Innovating Foundation of Research Institute of Petroleum Exploration & Development, PetroChina and the Outstanding Doctoral Dissertation Support Foundation of China University of Geo-sciences (Beijing)
文摘Biostratigraphically constrained sequences at the Wushi Yingshan and Kalpin Cement Plant sections (Kalpin Region; Tarim Basin) were densely sampled for geochemical studies. Carbonates across the Cambrian-Ordovician boundary of both sections mainly record negative carbon isotope values. Stable isotope curves show four negative and four positive excursions appearing alternately at the Wushi Yingshan section and five negative alternating with five positive excursions at the Kalpin Cement Plant section. The carbon isotope logs of these two sections are correlated with the international Cambrian-Ordovician boundary key sections: (1) Dayangcha section in China, (2) Green Point section in Canada, (3) Black mountain section in Australia and (4) Lowson Cove section in USA. These correlations suggest that the Cambrian-Ordovician boundary of the Wushi Yingshan section and the Kalpin Cement Plant section can be placed within a particular horizon that also corresponds to the observed biostratigraphic units.
