Earthquake-induced chains of geologic hazards: Patterns, mechanisms, and impacts

Reviews of Geophysics
By: , and 

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Abstract

Large earthquakes initiate chains of surface processes that last much longer than the brief moments of strong shaking. Most moderate- and large-magnitude earthquakes trigger landslides, ranging from small failures in the soil cover to massive, devastating rock avalanches. Some landslides dam rivers and impound lakes, which can collapse days to centuries later, and flood mountain valleys for hundreds of kilometers downstream. Landslide deposits on slopes can remobilize during heavy rainfall and evolve into debris flows. Cracks and fractures can form and widen on mountain crests and flanks, promoting increased frequency of landslides that lasts for decades. More gradual impacts involve the flushing of excess debris downstream by rivers, which can generate bank erosion and floodplain accretion as well as channel avulsions that affect flooding frequency, settlements, ecosystems, and infrastructure. Ultimately, earthquake sequences and their geomorphic consequences alter mountain landscapes over both human and geologic time scales. Two recent events have attracted intense research into earthquake-induced landslides and their consequences: the magnitude M 7.6 Chi-Chi, Taiwan earthquake of 1999, and the M 7.9 Wenchuan, China earthquake of 2008. Using data and insights from these and several other earthquakes, we analyze how such events initiate processes that change mountain landscapes, highlight research gaps, and suggest pathways toward a more complete understanding of the seismic effects on the Earth’s surface.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Earthquake-induced chains of geologic hazards: Patterns, mechanisms, and impacts
Series title Reviews of Geophysics
DOI 10.1029/2018RG000626
Volume 57
Year Published 2019
Language English
Publisher Wiley
Contributing office(s) Earthquake Hazards Program, Geologic Hazards Science Center
Description 83 p.
First page 421
Last page 503