摘要
本研究区广泛发发育一套南沱期杂砾岩,其成因一直存在冰川和泥石流之争。本文综合冰成岩的多成因标志,与重力流的沉积特征进行了比较和区别,为冰川论者补充了可信的证据;并且得出本区南沱期既有冰川作用、泥石流作用,又有大量火山碎屑物质加入。作者重点研究了5种沉积类型的杂砾岩的成因和环境,且认为这一研究成果对该地区的南沱期古气候和古环境的恢复具有较大意义。
A set of Nantou diamictite is widely distributed in Sichuan province and neghbouring regions. There is disputy about
its geneses. Is it of glaciation or mudflow? This article adds some incontrovertible proof for glacial theory on the basis of
multigenses sings of glacigene rocks, correlation and difference of mudflow sedimentary chacacteristics with glacigene
rocks, and supports the concept that there were glaci-ation and gravityflow and also interelated with much pyroclastic ma-
terial during Nantou period. The author emphasizes the study of geneses and environment of diamictite form five sedi-
mentary types, and considers that this research should be of some significance for restoration of Nantou paleoclimate and
paleoenvironment in this region.
关键词
震旦纪
南沱期
沉积类型
杂砾岩
Nantou period
geneses of diamictite
glaciation
mudflow(gravity flow)
sedimentary types
