赣东北地区构造演化的新认识

NEW UNDERSTANDING OF THE TECTONIC EVOLUTION IN NORTHEAST JIANGXI AREA

根据近几年来赣东北地区的区域地质调查及科研工作所获的地质资料、化石资料和实测数据，论述了该区晋宁期以来的构造演化，提出了以下看法：①该区是一个多期造山作用的复合体，它经历了褶皱基底形成、洋陆转化和陆内发展三大阶段和晋宁期、加里东期、印支期、燕山期四个构造旋回；②早古生代该区存在一小洋盆；③加里东期构造旋回在赣东北地区是明显的，其造山作用是存在的，并由此奠定了该区构造分区的总体格局。

Based on geological information,fossil data and laboratory data collected from regional geological survey and scientific research in the Northeast Jiangxi area in recent years ,this paper deals with the tectonic evolution since the Jinningean Period, arriving finally at the following conclusions:1)This area has undergone multistage orogeny involving three major stages of the formation of folded basement, the ocean-continent transformation and the intracontinental development,and four tectonic cycles of the Jinningean,the Caledonian,the Indosinian and the Yanshanian; 2)A small oceanic basin was present in this area during the Early Palaeozoic; and 3)The Caledonian tectonic cycle and orogeny are significant, and are responsible for the overall framework of tectonic divisions in this area.