MINES AND GEOSCIENCES BUREAU
REGION V - BICOL

GEO HAZARD MAPS  (1:50,000 Scale): 
Nabua, Camarines Sur, Philippines

Flood Hazard Susceptibility Map - Flood hazard susceptibility zones were derived based on the geomorphological analysis of landforms and the fluvial system. Information on flood occurrences, flood depths, duration of inundation as well as topographic information supported the geomorphologically-based flood.

Liquefaction Potential Map - There are no reported liquefaction occurrences based on several field interviews. However, zones of different liquefaction potential were derived based on the geomorphological analysis of the study area following previous studies made by Iwasaki and Yasuda.

Landslide Hazard Susceptibility Map. Landslide hazard susceptibility zones were derived through qualitative map combination using lithology, geomorphology, slope gradient and fault distance. GIS was used in the map combination and subjective weights were assigned to each unit in the parameter map.

Ground Settlement Susceptibility Map. Areas of possible ground settlement were delineated through the analysis of the geomorphological lay of the study area, the sub-surface soils and the ground water levels.

Susceptibility To Ground Subsidence Due To Karst. Susceptibility map for ground susbsidence due to karst processes was primarily derived from the lithologic map of the study area. Field observations on sinkholes and ground subsidence observed on concrete roads and damaged houses supported the mapping.