朝鲜平南盆地叠加褶皱构造特征

对于朝鲜平南盆地沉积盖层内发育的倒转褶皱，过去一般认为是直立褶皱的次级从属褶皱。通过对平南盆地内倒转褶皱发育区详细的地质调查，结合煤炭开发过程中获得的地质及钻探资料，提出平南盆地内叠加褶皱的主要识别标志为：地质平面图上呈现不同类型的两组褶皱脊线的交叉；倒转褶皱的轴面被直立褶皱改造弯曲；直立褶皱的两翼发育的倒转褶皱表现为两组牵引褶皱。查明了平南盆地存在3个阶段的褶皱构造：第一阶段为东西向的倒转褶皱，形成于印支期；第二阶段褶皱为东西向的直立褶皱，形成于早燕山期；第三阶段褶皱为北北东向的直立褶皱，形成于晚燕山期。

Characteristics of Superposed Folds of Pyongnam Basin in Korean Peninsula

The inverted folds developed in the sedimentary cap rocks in the Pyongnam basin are generally considered to be subordinate folds of upright folds. According to the detailed investigation and the geological and drilling data obtained in the process of coal development, we think that the main recognition marks of the superposed folds in the basin are as follows:The intersection of two different ridge lines of fold on the geological plane map; The axial surface of inverted folds reformed by upright folds; The inverted folds that developed in the two limbs of upright folds and showed the nature of two groups of traction folds. There are three stages of folds identified in the Pyongnam basin:the first stage is the E-W trending inverted folds formed in Indosinian stage; the second stage is the E-W trending upright folds formed in Early Yanshanian stage; and the third stage is the NNE trending upright folds formed in Late Yanshanian stage.