陈旭,戎嘉余,樊隽轩,詹仁斌,C.E.Mitchell,D.A.T.Harper,M.J.Melchin,彭平安,S.C.Finney,汪啸风

• 1:现代古生物学和地层学国家重点实验室 中国科学院南京地质古生物研究所
• 2:现代古生物学和地层学国家重点实验室
• 3:中国科学院南京地质古生物研究所
• 4:现代古生物学和地层学国家重点实验室

摘要(Abstract)：

赫南特阶(上奥陶统)的全球界线层型剖面和点位确立在中国宜昌王家湾北剖面观音桥层底界之下0.39m处。该剖面位于中国湖北省宜昌市以北42km处的王家湾村,经纬度为30°58′56″N、111°25′10″E。赫南特阶底界的GSSP点位以笔石Normalograptusextraordinarius的首次出现层位(FAD)为标志。碳同位素在此层位显示的正漂移以及N.ojsuensis的首现可作为第二标志。赫南特阶始于自Diceratograptusmirus亚带开始的全球生物大灭绝事件的主幕之后。王家湾北剖面出露完整,沉积和生物序列连续,笔石和壳相动物化石丰富并保存良好,王家湾北、王家湾南和王家湾小河边剖面都发育了合适的沉积相和生物相并具有广泛对比的潜力。该地区地质构造简单,岩石未经历较强的变质作用,且交通便利。王家湾小河边剖面尤其适合进行化学地层学研究和同位素年龄的测定。建立赫南特阶底界的全球界线层型剖面和点位的提案报告于2004年10月被国际地层委员会奥陶系分会通过,经补充完善后,于2006年2月被国际地层委员会通过,同年5月被国际地科联正式批准。

关键词(KeyWords)： 奥陶系;赫南特阶;全球界线层型剖面和点位(GSSP)

Abstract:

Keywords:

基金项目(Foundation): 中国科学院(KZCX2-SW-129,KZCX3-SW-149);; 国家科技部(2001DEA20020-3);; 美国自然科学基金EAR0107056项目资助。

作者(Author): 陈旭,戎嘉余,樊隽轩,詹仁斌,C.E.Mitchell,D.A.T.Harper,M.J.Melchin,彭平安,S.C.Finney,汪啸风

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