Submarine mass wasting and associated tsunami risk offshore western Thailand, Andaman Sea, Indian Ocean

Schwab, Julia, Krastel, Sebastian, Grün, Matthias, Gross, F., Pananont, P., Jintasaeranee, P., Bunsomboonsakul, S., Weinrebe, Wilhelm and Winkelmann, Daniel (2012) Submarine mass wasting and associated tsunami risk offshore western Thailand, Andaman Sea, Indian Ocean Natural Hazards and Earth System Sciences, 12 (8). pp. 2609-2630. DOI 10.5194/nhess-12-2609-2012.

[img]
Preview
Text
nhess-12-2609-2012.pdf - Published Version
Available under License ["licenses_description_cc_by_3.0" not defined].

Download (14Mb) | Preview

Supplementary data:

Abstract

2-D seismic data from the top and the western slope of Mergui Ridge in water depths between 300 and 2200 m off the Thai west coast have been investigated in order to identify mass transport deposits (MTDs) and evaluate the tsunamigenic potential of submarine landslides in this outer shelf area. Based on our newly collected data, 17 mass transport deposits have been identified. Minimum volumes of individual MTDs range between 0.3 km3 and 14 km3. Landslide deposits have been identified in three different settings: (i) stacked MTDs within disturbed and faulted basin sediments at the transition of the East Andaman Basin to the Mergui Ridge; (ii) MTDs within a pile of drift sediments at the basin-ridge transition; and (iii) MTDs near the edge of/on top of Mergui Ridge in relatively shallow water depths (< 1000 m). Our data indicate that the Mergui Ridge slope area seems to have been generally unstable with repeated occurrence of slide events. We find that the most likely causes for slope instabilities may be the presence of unstable drift sediments, excess pore pressure, and active tectonics. Most MTDs are located in large water depths (> 1000 m) and/or comprise small volumes suggesting a small tsunami potential. Moreover, the recurrence rates of failure events seem to be low. Some MTDs with tsunami potential, however, have been identified on top of Mergui Ridge. Mass-wasting events that may occur in the future at similar locations may trigger tsunamis if they comprise sufficient volumes. Landslide tsunamis, emerging from slope failures in the working area and affecting western Thailand coastal areas therefore cannot be excluded, though the probability is very small compared to the probability of earthquake-triggered tsunamis, arising from the Sunda Trench.

Document Type: Article
Additional Information: WOS:000309616500016
Keywords: Landslides and Debris Flow; Tsunami; Submarine mass wasting, tsunami potential, Thailand, Mergui Ridge, Indian Ocean; PASSIVE CONTINENTAL MARGINS; GRAND-BANKS EARTHQUAKE; PAPUA-NEW-GUINEA; LANDSLIDE TSUNAMI; SOURCE MECHANISM; RIFT BASINS; TECTONIC EVOLUTION; PETROLEUM SYSTEMS; INTERNAL SOLITONS; JULY 1998
Research affiliation: OceanRep > The Future Ocean - Cluster of Excellence > FO-R06
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Marine Geodynamics
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-JRG-B4 Submarine Hazards
OceanRep > The Future Ocean - Cluster of Excellence
Refereed: Yes
DOI etc.: 10.5194/nhess-12-2609-2012
ISSN: 1561-8633
Projects: MASS, Future Ocean
Date Deposited: 26 Sep 2012 08:42
Last Modified: 12 Mar 2017 15:35
URI: http://eprints.uni-kiel.de/id/eprint/15416

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...