Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zon...Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zone, Paragondolella bifurcata Zone and Neogondolella constricta Zone. These zones indicate that the upper Guanling Formation consists of strata from the Bithynian to the lllyrian of the Anisian. Appearance of Neogondolella constricta suggests that the Anisian/Ladinian boundary might be in the overlying Yangliujing Formation. The Panxian Fauna with well-preserved marine reptile and fish fossils is proved to belong to the lower part of the conodont Nc. kockeli Zone in the studied area. Thus, the age of the Panxian Fauna could be the early Pelsonian of the Anisian.展开更多
罗平生物群产出于关岭组二段,该段大凹子精细剖面细致的沉积学描述记录显示,剖面岩性变化趋势为:从生物扰动灰岩到含硅质结核的条带泥晶灰岩(钙屑浊积岩)向白云岩演化。剖面详细的牙形石生物地层研究表明,牙形石带属于Nicoraella kockel...罗平生物群产出于关岭组二段,该段大凹子精细剖面细致的沉积学描述记录显示,剖面岩性变化趋势为:从生物扰动灰岩到含硅质结核的条带泥晶灰岩(钙屑浊积岩)向白云岩演化。剖面详细的牙形石生物地层研究表明,牙形石带属于Nicoraella kockeli带,同时该带可分两个亚带,即Nicoraella kockeli type 1亚带和Nicoraella kocke-li type 2亚带。牙形石生物地层年代确定在Anisian期的Pelsonian亚期。通过大凹子剖面含牙形石段产出环境分析表明:深灰色具脉状层理含泥质灰岩的开阔台地相沉积环境牙形石产出较少且保存一般,而深黑色纹层状泥晶灰岩段台间盆地相沉积环境中牙形石产出丰富且保持完好。大凹子剖面沉积构造研究表明:罗平生物群产出于台间盆地相钙屑浊流沉积环境。展开更多
基金This study was financially supported by grants from the"985"project of Peking University,National Natural Science Foundation of China(grant 40272005)the Major Basic Research Projects of China(grant G2000077700).
文摘Detailed conodont analysis on the Yangjuan-Chupiwa section, Xinmin, Panxian County, Guizhou Province, revealed a conodont sequence including four Anisian conodont zones, viz. Nicoraella germanica Zone, Nc. kockeli Zone, Paragondolella bifurcata Zone and Neogondolella constricta Zone. These zones indicate that the upper Guanling Formation consists of strata from the Bithynian to the lllyrian of the Anisian. Appearance of Neogondolella constricta suggests that the Anisian/Ladinian boundary might be in the overlying Yangliujing Formation. The Panxian Fauna with well-preserved marine reptile and fish fossils is proved to belong to the lower part of the conodont Nc. kockeli Zone in the studied area. Thus, the age of the Panxian Fauna could be the early Pelsonian of the Anisian.
文摘罗平生物群产出于关岭组二段,该段大凹子精细剖面细致的沉积学描述记录显示,剖面岩性变化趋势为:从生物扰动灰岩到含硅质结核的条带泥晶灰岩(钙屑浊积岩)向白云岩演化。剖面详细的牙形石生物地层研究表明,牙形石带属于Nicoraella kockeli带,同时该带可分两个亚带,即Nicoraella kockeli type 1亚带和Nicoraella kocke-li type 2亚带。牙形石生物地层年代确定在Anisian期的Pelsonian亚期。通过大凹子剖面含牙形石段产出环境分析表明:深灰色具脉状层理含泥质灰岩的开阔台地相沉积环境牙形石产出较少且保存一般,而深黑色纹层状泥晶灰岩段台间盆地相沉积环境中牙形石产出丰富且保持完好。大凹子剖面沉积构造研究表明:罗平生物群产出于台间盆地相钙屑浊流沉积环境。