FN Archimer Export Format
PT J
TI Indentation of the Philippine Sea plate by the Eurasia plate in Taiwan: Details from recent marine seismological experiments
BT 
AF LALLEMAND, Serge
   THEUNISSEN, Thomas
   SCHNURLE, Philippe
   LEE, Chao-Shing
   LIU, Char-Shine
   FONT, Yvonne
AS 1:1;2:2;3:3;4:4;5:5;6:6;
FF 1:;2:;3:PDG-REM-GM-LGG;4:;5:;6:;
C1 Univ Montpellier 2, CNRS, F-34095 Montpellier 05, France.
   IRAP, Observ Midi Pyrenees, Toulouse, France.
   IFREMER, Plouzane, France.
   NTOU, Keelung, Taiwan.
   NTU, Inst Oceanog, Taipei, Taiwan.
   Univ Nice Sophia Antipolis, Inst Rech Dev, Observ Cote Azur, Geoazur, France.
C2 UNIV MONTPELLIER, FRANCE
   IRAP, FRANCE
   IFREMER, FRANCE
   UNIV NATL TAIWAN OCEAN NTOU, TAIWAN
   UNIV NATL TAIWAN NTU, TAIWAN
   UNIV NICE, FRANCE
SI BREST
SE PDG-REM-GM-LGG
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
   copubli-int-hors-europe
IF 2.866
TC 30
UR https://archimer.ifremer.fr/doc/00149/26048/24164.pdf
LA English
DT Article
DE ;Arc-continent collision;Local tomography;Tear, subduction;Intra-oceanic slicing;Slab break-off
AB We analyze in this study a new set of marine data including 3D local tomography, 1992-2008 relocated earthquakes and two recent multichannel seismic lines to characterize the deformation style in the collision area offshore east Taiwan. We have mapped in detail the Mohos of the converging plates as well as the subduction interface with a resolution never reached before. We show that the sharp continental subduction of the Eurasia plate, beneath the middle part of the Central Range, indents the Philippine Sea plate (PSP) as attested by intra-oceanic slicing and incipient subduction of the PSP beneath the east coast of Taiwan. The westernmost part of the PSP slab is probably experiencing a beginning of break-off as attested by NW-trending en-echelon shear zones beneath the southern slope of the southern Ryukyu arc (SRA). These en-echelon shear zones have a sinistral component favored by the "collision-free" subduction of the PSP north of 24 degrees 30'N. The down-faulting of the subduction interface forms ramps along which earthquakes clusterize. Three M7 subduction earthquakes occurred offshore Suao city along these ramps with a recurrence interval of about 40 years: 1920 M(w)7.7, 1963 M(w)7.2 and 2002 M(w)7.1 events. The 1966 M(w)6.0-7.5 earthquakes sequence likely outlines a WNW-ESE left-lateral intra-slab shear zone. The SRA upper plate accommodates the complex geometry and deformation of the subducting PSP through seismic deformation. Shallow high velocities fringing the Luzon volcanic arc (LVA) beneath the Longitudinal Valley and north of the southernmost Ryukyu forearc basins are interpreted as relics of the LVA forearc basement squeezed in the collision zone. Based on the accommodation of a large part of the convergence through shortening within the PSP and the subsequent segmentation of the shallow subduction interface, we consider that the nucleation of a M-w >= 8 earthquake along the southernmost Ryukyu megathrust is unlikely.
PY 2013
PD MAY
SO Tectonophysics
SN 0040-1951
PU Elsevier Science Bv
VL 594
UT 000319791100005
BP 60
EP 79
DI 10.1016/j.tecto.2013.03.020
ID 26048
ER

EF