浙江新近纪嵊县组地层特征及其化石研究进展
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摘要
嵊县组是中国东南陆相晚新生代的经典地层,然而其地质年代一直存在争议,其有关单位名称的使用也较混乱.综合该地区已发表的岩石地层、年代地层和生物地层资料,遵循优先律原则指出浙东新近系含化石层位的地层单位宜采用嵊县组,基于地层对比其绝对年龄为13.0～10.5 Ma或9.4 Ma(40Ar-39Ar坪法)或13.00～10.38 Ma(K-Ar法),时代应为中新世.同时,对该区古植物和孢粉及古气候成果进行了简单列述和评价,就该套地层的未来研究方向提出展望.
The Shengxian Formation is a suite of representative strata of the continental late cenozoic in Southeast China, but its geologic age is controversial and the lithostratigraphic unit is adopted in a confused state. Based on comprehensive analyses of previously published litho-, chrono- and biostragraphic data, the Shengxian Formation should be adopted for the fossiliferous horizons of the neogene system in Zhejiang as a valid lithostratigraphic nomenclature following the law of priority, and age of the fossiliferous horizons should be confined to the miocene based on a time interval of 13.0～10.5 Ma or 9.4 Ma(40Ar-39Ar method) or 13.00～10.38 Ma(K-Ar method) obtained by radioisotope stratigraphical correlations. Additionally, relevant paleobotanical, palynological and paleoclimatic studies concerning this suite of strata were briefly summarized and evaluated, and prospects for future research were presented.
The Shengxian Formation is a suite of representative strata of the continental late cenozoic in Southeast China, but its geologic age is controversial and the lithostratigraphic unit is adopted in a confused state. Based on comprehensive analyses of previously published litho-, chrono- and biostragraphic data, the Shengxian Formation should be adopted for the fossiliferous horizons of the neogene system in Zhejiang as a valid lithostratigraphic nomenclature following the law of priority, and age of the fossiliferous horizons should be confined to the miocene based on a time interval of 13.0～10.5 Ma or 9.4 Ma(40Ar-39Ar method) or 13.00～10.38 Ma(K-Ar method) obtained by radioisotope stratigraphical correlations. Additionally, relevant paleobotanical, palynological and paleoclimatic studies concerning this suite of strata were briefly summarized and evaluated, and prospects for future research were presented.
引文
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[37]Hu Ya-qin,Ferguson D K,Li Cheng-sen,et al.Alseodaphne(Lauraceae)from the pliocene of China and its paleoclimatic significance[J].Review of Palaeobotany and Palynology,2007,146(1):277-285.
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