云南沾益泥盆系龙华山组、西冲组孢子生物地层研究  

DEVONIAN MIOSPORE BIOSTRATIGRAPHY OF THE LONGHUASHAN AND XICHONG FORMATIONS IN ZHANYI OF YUNNAN

作　　者：田家杰[1] 朱怀诚[1] 

机构地区：[1]中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室,江苏南京210008

出　　处：《地层学杂志》2005年第4期311-316,322,共7页Journal of Stratigraphy

基　　金：中国科学院知识创新工程方向项目(KZCX2-SW-130)资助。

摘　　要：云南沾益龙华山剖面泥盆系龙华山组和西冲组上段含丰富的孢子化石,按某些重要孢子类群的数量变化关系和重要分子的发生、发展和消失情况,分为下部龙华山组的RP孢子组合带和西冲组上段的VM孢子组合带。RP组合带含有早泥盆世典型分子,VM组合带含有吉维期(Givetian)晚期才在国内外出现的典型分子。结合其他门类化石研究,认为龙华山组的地质时代为泥盆纪布拉格期(Pragian)中期至埃姆斯期(Emsian)早期,西冲组上段为吉维期(Givetian)晚期,可能包括弗拉斯期(Frasnian)早期。当前研究还揭示,滇东在吉维期(Givetian)晚期Cyr-tospora cristifer已经丰富,较国内外其他地区该类孢子出现的时代(最早为弗拉斯期晚期)明显要早,据此提出了滇东可能是Cyrtospora cristifer的发源地。This paper deals with the Devonian miospores from the Longhuashan and Xichong formations in Zhanyi of Yunnan. Two spore assemblage zones have been recognized, namely Retusotriletes rotundus-Apiculiretusispora plicata （RP） spore assemblage zone in the Longhuashan Formation, and Archaeozonotriletes variabilis-Cymbosporites magnificus （VM） spore assemblage zone in the upper part of the Xichong Formation. The RP assemblage zone is considered to be mid-Pragian to early Emsian in age, and the VM assemblage zone is considered to be late Givetian and possibly early Frasnian included in age. Representatives of Cyrtospora cristifer were found in late Givetian in east Yunnan, which is earlier than other places of the world （the known earliest record is late Frasnian）. This suggests that east Yunnan might be the cradle of Cyrtospora cristifer.

关 键 词：孢子 龙华山组 西冲组 泥盆纪 沾益 云南 

分 类 号：P534.44[天文地球—古生物学与地层学]