THE CHARACTERISTICS OF THE FAULT SYSTEM AND ITS CONTROLLING FOR THE GEOLOGICAL HAZARDS IN THE WESTERN QINLING

Based upon the investigation of the characteristics of fault systems and analysis for the relationship between the fault systems and landslide, debris flow et al geological hazards in the westen Qingling, the controlling function of fault system for geological hazard development is discussed. It is proposed that fault systems and its activities are essential factors for the development of geological hazards although geological hazards are actually the results of complex and composite actions of interior and exterior dynamic geological processes. The controlling functions of fault system for geological hazard development could be direct or indirect, mainly as follow, (1)the geological hazards generally develop along the faults, which often determines the intensity and spatial distribution of geological hazards; (2) the fractural zone and influence zone of faults often provide mass debris substance and structural slide faces for landslide and mud-debris flow; (3) the fault activities, especially earthquake activity of faults are the important induced factor for geological hazards; (4) fractured rocks and geomorphic height contrasts for the prolonged activity of faults provide the favorite conditions for water corrosion, which would develop the slope geomorphic condition for geological hazards. Therefore in studying landslide and mud-debris flow, we should put them under the regional geological background, especially regional fault framework, fault zone structural features and fault activities, to understand its development..