Document Type
Article
Department or Administrative Unit
Geological Sciences
Publication Date
11-23-2011
Abstract
Stratigraphic evidence is found for two coseismic subsidence events that underlie a floodplain 20 km south of Padang, West Sumatra along the Mentawai segment (0.5°S–0.3°S) of the Sunda subduction zone. Each earthquake is marked by a sharp soil‐mud contact that represents a sudden change from mangrove to tidal flat. The earthquakes occurred about 4000 and 3000 cal years B.P. based on radiocarbon ages of detrital plant fragments and seeds. The absence of younger paleoseismic evidence suggests that late Holocene relative sea level fall left the floodplain too high for an earthquake to lower it into the intertidal zone. Our results point to a brief, few thousand year window of preservation of subsidence events in tidal‐wetland stratigraphic sequences, a result that is generally applicable to other emergent coastlines of West Sumatra.
Recommended Citation
Dura, T., C. M. Rubin, H. M. Kelsey, B. P. Horton, A. Hawkes, C. H. Vane, M. Daryono, C. G. Pre, T. Ladinsky, and S. Bradley (2011), Stratigraphic record of Holocene coseismic subsidence, Padang, West Sumatra, J. Geophys. Res., 116, B11306, doi:10.1029/2011JB008205.
Journal
Journal of Geophysical Research: Solid Earth
Rights
Copyright 2011 by the American Geophysical Union.
Included in
Geology Commons, Geophysics and Seismology Commons, Stratigraphy Commons, Tectonics and Structure Commons
Comments
This article was originally published in Journal of Geophysical Research: Solid Earth. The full-text article from the publisher can be found here.