滇东牛头山地区早震旦世沉积相及大地构造环境

野外调查和室内分析表明,牛头山地区陆良组、牛头山组应属下震旦统,其沉积相类型自下而上可划分为辫状河相、河口湾相、浅海相、滨海相、浅海相及三角洲相。“牛头山古陆”在早震旦世是不存在的。牛头山地区当时为被动大陆边缘。

THE SEDIMENTARY FACIES AND TECTONIC SETTING OF EARLY SINIAN IN NIUTOUSHAN REGION, EASTERN YUNNAN

Field investigation and laboratory analysis show that Luliang formation and Niutoushan formation should belong to Lower Sinian in Niutoushan region. Their sedimentary facies can be subdivided, from bottom to top, into braided river fa- cies, estuarine facies, shallow-sea facies, littoral facies, shallow-sea facies and delta facies. In Early Sinian there was not a "Nlutoushan old land". Niutoushan region belonged to a passive continental margin at that time.