Neotectonic and Geomorphological Characteristics of the Ma Pi Leng Area (Ha Giang Province, North Vietnam): Implications for Improving the Worth of Vietnamese Geological Heritage

摘要

Ma Pi Leng area is the core part of Dong Van karst plateau geopark, and is a region of high diversity of geology and tectonics in Vietnam. This region has experienced strong uplift motions that have created three grades of regional relief: 1400–1600 m; 1100–1200 m and 500–600 m. This geomorphology is in turn strongly eroded by the stream systems and divided into different structural blocks controlled by the faults. During the neotectonic stage, several modes of faulting have occurred in Ma Pi Leng such as strikeslip, normal, extension, riverse faults. The NW–SE fault system had a decisive role in determining the structural pattern of the region. The tectonic fractures, at the largest scale, are hundreds of meters high and up to a kilometer long. Tectonic activities, together with exogenic processes, have made regional relief strongly diverse with strips of horsts and grabens as well as laddersteps-shaped escarpments, inverse topography, high cliffs and deep canyons. Besides that there are also the caves at varying levels of height, chains of sinkholes, and pyramidal mountainous peaks. Ma Pi Leng area is truly majestic and worthy of tourist attractions both in terms of scientific value and natural landscape.