APPLICATION OF HIGH RESOLUTION DIGITAL ELEVATION MODELS FOR LANDSLIDE SUSCEPTIBILITY MAPPING IN THE URBAN GROWTH AREA OF URCUQUI, ECUADOR

Recent years have seen a rapid worldwide rise in the likelihood of mass movements that affect humans. This increase is mainly due to semi-urban settlements in landslide-prone areas. In Ecuador, 35% of the population lives in areas threatened by various phenomena of mass wasting such as mudslides, landslides, and erosion, triggered mainly by intense rainfall. The lack of government regulation results in frequent construction of buildings in marginal areas of very high risk, which increases the degree of vulnerability. After reviewing the cartographic information on hazards due to mass movements in the town of Urcuqui compiled by the Ecuadorian Secretariat for Risk Management, it is observed that there is a high level of landslide risk. Some slopes are as steep as 50° to even with poorly cohesive soils. Geographical Information Systems and remote sensing are very useful tools for preparing landslide susceptibility maps. However, high-resolution satellite data access is limited in certain areas. An alternative is the use of unmanned aerial vehicles (drones) for 3D mapping. The generation of high-resolution digital elevation models (DEMs) can help map and monitor areas of high vulnerability to natural hazards, such as landslides. Using repeat measurements, this method will allow us to identify and quantify slip rates of mass movements in specific areas on a local . The slow landslides identified can become catastrophic events if we do not apply this kind of mitigation methods. Additional benefits are the relatively low cost of drone photogrammetry, easiness to do periodical measurements and secure monitoring from a distance The results obtained are useful for disaster risk management of slope processes as well as land use planning.