FN Archimer Export Format
PT J
TI P-wave velocity structure of the southern Ryukyu margin east of Taiwan: Results from the ACTS wide-angle seismic experiment
BT 
AF KLINGELHOEFER, Frauke
   BERTHET, T.
   LALLEMAND, S.
   SCHNURLE, Philippe
   LEE, C. -S.
   LIU, C. -S.
   MCINTOSH, K.
   THEUNISSEN, T.
AS 1:1;2:2;3:2;4:1;5:3;6:4;7:;8:2;
FF 1:PDG-REM-GM-LGG;2:;3:;4:PDG-REM-GM-LGG;5:;6:;7:;8:;
C1 IFREMER, Dep Marine Geosci, Ctr Brest, F-29280 Plouzane, France.
   Univ Montpellier 2, CNRS, Geosci Montpellier, F-34095 Montpellier 5, France.
   NTOU, Dept Geophys, Keelung, Taiwan.
   NTU, Inst Oceanog, Taipei, Taiwan.
C2 IFREMER, FRANCE
   UNIV MONTPELLIER, FRANCE
   UNIV NATL TAIWAN OCEAN NTOU, TAIWAN
   UNIV NATL TAIWAN NTU, TAIWAN
SI BREST
SE PDG-REM-GM-LGG
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
   copubli-int-hors-europe
IF 2.68
TC 17
UR https://archimer.ifremer.fr/doc/00116/22750/40296.pdf
LA English
DT Article
DE ;Ryukyu Trench;Marine seismics;Wide-angle seismics;Subduction processes
AB An active seismic experiment has been conducted across the southern Ryukyu margin east of Taiwan over the whole trench-arc-backarc system in May 2009. Twenty-four ocean bottom seismometers (OBS) were deployed from the Ryukyu trench to the southern Okinawa trough over the Ryukyu arc and forearc. Wide angle seismic data were recorded by the OBS array while coincident reflection seismic data were acquired using a 6 km long streamer and a 6600 cubic inch seismic airgun array. Results from tomographic inversion of 21091 travel time picks along this line allowed us to image crustal structures of the Ryukyu margin down to a depth of 25 km. The transect has been designed to provide a better seismic velocity structure of the subduction zone in a highly deformed area that has produced an M8 earthquake in 1920. The line crosses a seismic cluster of earthquakes which source mechanisms are still poorly understood. The subducting oceanic crust of the Huatung Basin is about 5-6 km thick. The underlying mantle exhibits low seismic velocities around 7.8 km/s suggesting some hydrothermal alterations or alteration of the upper mantle through faults generated by the flexure of the subducting plate as it enters the subduction. Low velocities, up to 4.5 km/s, associated with the accretionary wedge are well imaged from the trench back to the Nanao forearc. A major result concerns the abrupt termination of the buttress at the rear of the accretionary wedge. Despite the low resolution of the tomographic inversion near the subduction interface, several lines of evidence supporting the presence of a low velocity zone beneath the toe of the forearc buttress could be established. The Moho beneath the Ryukyu non-volcanic arc is located at a depth around 25 km depth. (C) 2011 Elsevier B.V. All rights reserved.
PY 2012
PD NOV
SO Tectonophysics
SN 0040-1951
PU Elsevier Science Bv
VL 578
UT 000312509000005
BP 50
EP 62
DI 10.1016/j.tecto.2011.10.010
ID 22750
ER

EF