江西石城县通天寨龟裂凸包景观成因初探

Study on Genesis of the Chap-Convex Hull Landscape in Shicheng Tongtian Castle in Jiangxi Province

基于野外调查和室内研究,对通天寨龟裂凸包景观的类型、成因、形成条件及演化过程进行了分析总结。根据发育的部位将龟裂凸包划分为层面龟裂凸包和断面龟裂凸包。根据形态特征,将龟裂凸包分为四边形龟裂凸包和不规则多边形龟裂凸包。通天寨龟裂凸包中的龟裂纹主要为构造作用形成的节理,龟裂凸包空间分布受区域主节理控制。部分小的裂纹是由表生作用过程中形成的,对形成典型的龟裂凸包具有重要意义。通天寨龟裂凸包的形成与该景区出露红层的岩石学性质、地层产状、构造特征及该地区的气候条件密切相关,最佳成景条件是厚层红色细砂或粉砂岩、地形坡度较陡、节理发育、气候湿润、强降雨频繁、地层裸露等。根据龟裂凸包景观的发育特征,将龟裂凸包的形成过程分为萌芽期、幼年期、成年期、老年期、消亡(新生)期5个阶段,不同阶段具有不同的形态特征。

Based on field survey and laboratory study, the types, geneses, formation conditions and evolution of the chap-convex hull landscape in Tongtian castle have been analyzed in this paper. The chap-convex hulls land- scape can be divided into bedding chap-convex hull and sectional chap-convex hull by its relationship with the red beds bedding. It also can be classified into quadrilateral and irregular polygons chap-convex hull by its shape. The cracks of the chap-convex hull are mainly structural joints, and the distributions of the chap-conxex hulls are controlled by the regional lord joints. Some cracks are formed by the hypergenesis during the red beds exposure, and have an important significance in the formation of the classic landscape. The formation of the chap-convex hull in Tongtian castle has a close relationship with petrology properties, attitude of stratum and structural feature of the red beds and regional weather conditions. The best conditions to form classic chap-convex hull are including thick red fine sand or siltstone, steep slope, developed joint, humid climate, frequent heavy rainfall and exposed strata. The evolution of this landscape can be divided into five stages, namely Germination stage, Infancy stage, adult stage, old stage and demise or rebirth stage based on the evolution features, and in different developing sta- ges the chap-convex hulls have different shape features.