Taiwan is an island with special geographical environments. The oblique convergence of tectonic
plates results in active orogeny, and the geological conditions are fragile and steep. Because of these geological conditions in the mountainous areas of Taiwan, landslides are prone to being triggered by heavy rainfall. Landslides threaten human lives and property. In the present study, 181 shallow landslides occurring after the 921 Earthquake of 1999 were selected as the research samples. The characteristics of shallow landslides were investigated through field investigations and data collection. The results showed that in the mountainous areas of Taiwan, shallow landslides occur mostly along hillsides with a southeast to west aspect; slope <50°; elevation <1200 m; and lithology associated
with the Sanhsia Group, its equivalents, and the LuShan Formation. In addition, shallow landslides are primarily induced by rainfall. These results are valuable references for formulating disaster mitigation policies and reducing potential loss of life and property damage. Moreover, the relationship between the area and volume of shallow landslides was investigated, and a log-linear formula that predicts the volume of shallow landslides based on the landslide area was proposed. This formula is valuable for quickly assessing the volume of shallow landslides during project planning.
Key Words : Shallow landslide, landslide character, landslide volume.