TY  - JOUR
JF  - Geophysical Research Letters
AV  - public
ID  - discovery94124
SN  - 0094-8276
N1  - Copyright 2005 by the American Geophysical Union
PB  - AMER GEOPHYSICAL UNION
Y1  - 2005/07/21/
VL  - 32
A1  - Bilek, SL
A1  - Conrad, CP
A1  - Lithgow-Bertelloni, C
IS  - 14
N2  - Subduction zone seismicity is highly variable. Great earthquakes occur at few subduction zones around the world, with significant variation in size and frequency of deep events. Interactions between overriding and subducting plates and slab pull strength for individual plates provide a framework for understanding these variations. Previous work suggests an inverse correlation between great earthquake moment release and the degree to which the subducted slab is connected to the surface plate. We find positive correlations between degree of plate- slab attachment and moment release from intermediate and deep earthquakes. This implies that shallow slab weakening that occurs at trenches where compressive stresses ( and great earthquakes) dominate not only detaches slabs from plates, but is maintained as the slab descends, discouraging deep seismicity. Regions of low shallow moment release are consistent with extensional shallow stress regimes and undamaged slabs. Such slabs maintain mechanical strength during descent and deform seismogenically at depth.
TI  - Slab pull, slab weakening, and their relation to deep intra-slab seismicity
KW  - Focus earthquakes
KW  -  Subduction zone
KW  -  Global survey
KW  -  Mantle
KW  -  Lithosphere
KW  -  Mechanism
KW  -  Constraints
KW  -  Parameters
KW  -  Stresses
UR  - http://dx.doi.org/10.1029/2005GL022922
ER  -