VULNERABILITY ZONING OF MAIN GEOLOGICAL HAZARDS IN CHANGCHUN-JILIN-TUMEN ECONOMIC ZONE

The synthetic risk index method is used for the vulnerability zoning of environmental geological hazards such as collapse, landslide and debris flow in Changchun-Jilin-Tumen Economic Zone. Precipitation is the most important factor inducing geohazards in the region, followed by topography and landform. Helong City, Longjing City, Yanji City, Hunchun City, part of Antu County, the upper reaches of Gaya River in Wangqing County and surrounding area of Tianchi Lake in Changbai Mountain are highly prone to the above geohazards, accounting for 22. 31% of the study area, with 726 geohazard sites and average density of 4. 52 sites per 100 km²; Low hilly areas such as Jiaohe City, Yongji County, Dunhua City and Wangqing County belong to medium susceptible area, accounting for about 48. 10% with 671 geohazard sites and average density of 1. 94 sites per 100 km²; Yitong County, Jilin City, Changchun City, Dehui County and Nong'an County are of low susceptible areas, accounting for about 29. 59% with 157 geohazard sites and average density of 0. 74 site per 100 km².