论文部分内容阅读
引言关于板块构造在前寒武纪活动带发展中之作用的辩论已有所评论(Kroner,1981)。古地磁证据虽然是有争议的,但它暗示着至少在早前寒武纪时期,单一大陆环境中大范围活动带内的发育实质上是“原地的”(Mc Elhinny和McWilliams,1977)。它基本上包含了整个硅铝层具有有限的发散和聚敛变形,而且多半有明显的位移和剪切作用。考虑到可能的太古代地幔和地壳构造控制,这里提出一个假想的图形,即早前寒武纪地壳剖面是由硅铝质的多边形微板块单元的镶嵌而组成的,它们对地壳和地幔作
INTRODUCTION Debates have been made about the role of plate tectonics in the development of Precambrian activity (Kroner, 1981). Although paleomagnetic evidence is controversial, it suggests that, at least in the early Precambrian times, development within a broad range of activity in a single continental environment was essentially “in situ” (Mc Elhinny and McWilliams, 1977). It basically contains the entire Si-Al layer has limited divergence and convergence deformation, and most of the obvious displacement and shear. Given the possible control of the Archean mantle and crustal structure, a hypothetical pattern is proposed here that the Early Precambrian crustal profile is composed of inlaid polygons of Si-Al polygons, which act on the crust and mantle