Morphologic expression of the accretion process in the SW margin of the Pacific of Colombia interpreted by means bathymetric high-resolution data
Abstract
Were recorded 9.750km2 of bathymetric high-resolution data using a multi-beam eco-sounder in the South Pacific margin of Colombia (1°25'N - 2°00'N and 78°44'W - 80°14'W), scenario of several great subduction earthquakes during the twentieth century (1906, Mw = 8.8; 1942, Mw = 7.8; 1958, Mw = 7.7, 1979, Mw=8.2). Among the most relevant morphological features is the presence of the Tumaco High, the Emerald Canyon, the Mira Canyon and the Ancon Fault, limited on the western by the Manglares High. The Mira Canyon defines a scar along 50km which could be associated to a recent landslide that displaced marine sediments between 50 and 1000m depth, probably triggered by one earthquake occurred in the area. The interpretation of seismic reflection and gravity data suggests the presence of the bathymetric highs as fragments of basement raised during the accretion process and/or the presence of oceanic asperities being brought during the subduction. Main geomorphological features in the study area
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFM.S53A1481V
- Keywords:
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- 1209 GEODESY AND GRAVITY / Tectonic deformation;
- 3070 MARINE GEOLOGY AND GEOPHYSICS / Submarine landslides;
- 7230 SEISMOLOGY / Seismicity and tectonics;
- 7240 SEISMOLOGY / Subduction zones