广东泥盆纪各时期古地理

DEVONIAN PALAEOGEOGRAPHY IN GUANGDONG

本文是在“广东泥盆纪岩相古地理及沉积、层控矿产远景预测”研究课题基础上写成的。广东泥盆纪地层相当发育,矿产丰富。“六五”期间一些科研和生产单位先后对广东泥盆纪沉积岩相和层控矿床进行过研究。本文主要介绍广东泥盆纪各时期古地理面貌、沉积盆地的发展演化。广东泥盆纪古地理主要受北东向和东西向超壳深断裂控制,这些断裂由加里东末期的挤压转化为泥盆纪时的北西—南东向和南北方向的拉张为主。

The Devonian palaeogeography in Guangdong was governed dominantly by NE- and EW-trending ultracrustal deep faults which resulted from compressional faulting at the end of the Caledonian and NW—SE- and NS-trending extensional faulting. The faulting cited above commanded not only the boundaries of uplifts and depressions, but also the temporal and spatial distribution of sedi-mentary facies belts as well as post-Devonian folding, faulting, magmatic activity and regional mineralization. The overall palaeogeographic outline was characterized by the framework with higher relief and shallower water depth in the east and south, and conversely n the west and north. The Devonian transgressions originated from the southwest and northwest, and the early and late stages of the Late Devonian represented maximum marine incursion and regression phases, respectively. The principal source of sediments lay to the Wuyi ancient land in the northeast and Southeast Guangdong ancient land(part of the Cathaysia)in the southeast on the basis of rock and mineral analysis, oblique bedding and gravel vector analysis.