Abstract: To address the frequent occurrence of rainstorms and the increasing risk of rockfall and landslide geological disasters in recent years, and to further improve the research system for collapse-landslide catastrophes in igneous rock areas of Northeast China, this paper systematically summarizes the disaster types and their hazard-causing mechanisms of rockfalls and landslides in igneous rock slopes of the Changbai Mountains, based on the 1 240 km field investigation along the Jilin section of National Highway G331. The results indicate that the development characteristics of igneous rock slope collapse-landslide hazards in Northeast China are closely related to volcanic eruption cycles and intrusion patterns. These can be classified into five types: soft-under-hard stratigraphic collapses caused by a single eruption cycle, unconformity-type stratigraphic collapses induced by late-stage eruptions, alternating soft-hard stratigraphic collapses resulting from rhythmic eruptions, differential-weathering stratigraphic collapses associated with quiescent eruptions, and intrusive-weathering stratigraphic collapses produced by localized magma intrusions. 

Key words: rock mass structure, Changbai Mountains, volcanic rock, collapse, landslide