Natural Gas Eruption Mechanism for Earthquake Landslides: Illustrated with Comparison between Donghekou and Papandayan Rockslide-Debris Flows

Abstract

This paper presents a new genesis and associated mechanism responsible for causing landslides and particular rapid and long runout landslides during earthquakes. This new genesis is the huge expansion power of highly compressed natural gas as the main force causing landslides during earthquake. The associated mechanism involves a rapid migration and transportation of highly compressed natural gas from deep crust through geological faults or discontinuities (weak zones) to slope grounds during earthquake. The gas expansion power suddenly breaks the ground rocks and soils. Instantly, it accelerates, erupts and ejects the broken rock fragments and soil particles (the debris) out of their original places and into the sky. Subsequently, the debris with high initial velocity or momentum rapidly fly, run and flow down the slope for long travel distance. During the flying, impacting and flowing, the debris can be further disintegrated. This paper uses the Donghekou and the Papandayan rockslide-debris flows as examples to illustrate the genesis and mechanism.