Long-term patterns of hillslope erosion by earthquake-induced landslides shape mountain landscapes

Wang, J. et al. (2020) Long-term patterns of hillslope erosion by earthquake-induced landslides shape mountain landscapes. Science Advances, 6(23), eaaz6446. (doi: 10.1126/sciadv.aaz6446) (PMID:32548261) (PMCID:PMC7274776)

Abstract

Widespread triggering of landslides by large storms or earthquakes is a dominant mechanism of erosion in mountain landscapes. If landslides occur repeatedly in particular locations within a mountain range, then they will dominate the landscape evolution of that section and could leave a fingerprint in the topography. Here, we track erosion provenance using a novel combination of the isotopic and molecular composition of organic matter deposited in Lake Paringa, New Zealand. We find that the erosion provenance has shifted markedly after four large earthquakes over 1000 years. Postseismic periods eroded organic matter from a median elevation of 722 +329/−293 m and supplied 43% of the sediment in the core, while interseismic periods sourced from lower elevations (459 +256/−226 m). These results are the first demonstration that repeated large earthquakes can consistently focus erosion at high elevations, while interseismic periods appear less effective at modifying the highest parts of the topography.

• Item Type: Articles
• Additional Information: This work was funded by the National Natural Science Foundation of China (41991322) and COFUND Junior Research Fellowship at Durham University to J.W.; Natural Environment Research Council Standard Grant to R.G.H., A.L.D., E.L.M., and J.D.H. (NE/P013538/1); and Rutherford Foundation Postdoctoral Fellowship to J.D.H. (RFTGNS1201-PD). The soil radiocarbon analysis was supported by NERC radiocarbon analysis allocation number 2170.1118.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Garnett, Dr Mark
• Authors: Wang, J., Howarth, J. D., McClymont, E. L., Densmore, A. L., Fitzsimons, S. J., Croissant, T., Gröcke, D. R., West, M. D., Harvey, E. L., Frith, N. V., Garnett, M. H., and Hilton, R. G.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Science Advances
• Publisher: American Association for the Advancement of Science
• ISSN: 2375-2548
• ISSN (Online): 2375-2548
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Science Advances 6(23):eaaz6446
• Publisher Policy: Reproduced under a Creative Commons License