Landslide Risk Evaluation in Central Provinces of Vietnam

Abstract

Open image in new window In central provinces of Vietnam, landslides are hazardous phenomena that occur frequently, destroying human life, damaging structures, infrastructure and adversely affecting living conditions. Assessing landslide risks (probability of landslide re-occurrence) poses a difficult challenge for all Vietnamese scientists and civil managers. For risk evaluation, we applied Japan Landslide Society’s Inspection sheet to study area with 261 landslide units were chosen for evaluation and developed 6 sheets of risk map. But this sheet shows geomorphological factors only, it does not mention geologic structures and weathering. The study area has a varied geologic composition with many stratigraphic unit and strata, original rocks have been found from Precambrian to Quaternary. Fieldwork shows that geologic conditions (such as geology age, bedrock lithology, bedrock structure, level of weathering) must play an important role in landslide occurrences in Vietnam. The authors propose and presume a new integrated inspection sheet that will combine two components: the first is geomorphology (as mentioned in the Japan Landslide Society’s Inspection sheet); the second is geology. With this component, it is also classified into large, medium and small categories, similar to the Japan Landslide Society’s Inspection sheet. A standard score system was created for the new integrated inspection sheet. Five landslide locations were trial application. Results present few differences when applying Japan Landslide Society’s Inspection sheet and new integrated inspection sheet. The new inspection sheet is the initial stage of development, presenting some limitations and should be discussed much more.