豫西前寒武纪汝阳群遗迹化石

TRACE FOSSILS FROM THE PRECAMBRIAN RUYANG GROUP OF WESTERN HENAN

本文研究的遗迹化石:Ruyangichnus loyuensis ichnogen. et ichnosp. nov., Torrowangea rosei Webby, Changchengia ichnosp., Squamodictyon (?) ichnosp.等发现于河南西部鲁山县和汝阳县的汝阳群云梦山组和北大尖组。根据同位素年龄值,微古植物和叠层石资料。产遗迹化石的汝阳群应相当于中元古代,可以和蓟县剖面的蓟县系相对比。除描述所发现的遗迹化石,还扼要论述了该遗迹化石群的演化意义。

The Precambrian trace fossils described in this paper were found in the Yunmengshan and Beidajian Formation of the Ruyang Group of Lushan and Ruyang, western Henan province. They include the following ichnotaxa: Ruyangichnus loyuensis ichnogen. et ichnosp. nov. , Tor-rowangea rosei Webby, Changchengia ichnosp. and Squamodictyon(?) ichnosp. and an uncertain ichnospecies. According to the data of isotopic ages, microfloras and stromatolites, the age of the Ruyang Group should be Middle Proterozoic, ranging from 1100 to 1400 Ma, so it may be correlated with the Middle Proterozoic Jixian System of the Jixian section. This paper also briefly discusses the significance of evolution of this trace fossil assemblage.