Preliminary study on the Late Quaternary activity of important active fault zones along the Yunnan-Tibet railway

Abstract

The Yunnan-Tibet railway is located in the southeastern edge of the Tibetan Plateau, where tectonic plates collide and the terrain rapidly changes. Along the line, active faults develops, earthquakes occur frequently, and the intensity of earthquakes is strong, moreover, geological disasters are frequent. Hence its planning, construction, and long-term operation face severe geological safety risks. More than 10 active fault zones have been developed along the Shangri La-Bomi section of the Yunnan-Tibet railway, including the Haba-Yulong Snow Mountain east foot fault zone, Zhongdian-Longpan fault zone, Deqin-Zhongdian-Daju fault zone, Weixi-Qiaohou fault zone, Jinsha river fault zone, Batang fault zone, Lancang river fault zone, Nujiang fault zone, Bianba-Luolong fault zone, and Jiali-Chayu fault zone. These active fault zones are highly affected by fault slip dislocations, creep deformation, and the risk of triggering strong earthquakes. There is an urgent need to determine the geometric distribution and activity of regional active fault zones. Based on previous research, remote sensing interpretation, and field investigations, this article summarizes and analyzes the geometric distribution, kinematic properties, slip rate and paleoearthquake sequence of more than 10 active fault zones along the route, providing basic information for the planning, construction and safe operation of major national projects such as the Yunnan-Tibet railway.

Keywords

• yunnan-tibet railway
• active fault zone
• fault activity
• late quaternary
• southeast edge of the tibetan plateau