On the relation between Geodetic strain Seismicity and

On the relation between Geodetic strain, Seismicity and fault frictional properties • Nepal • Sumatra • Taiwan

Sumatra • Variability of interseismic coupling (using PCAIM on coral data). • Analysis of strong motion data and high rate GPS • Analysis of aftershocks • Modeling of large scale postseismic relaxation • Cause of earthquake clustering in Sumatra • Inversion of postseismic data for heterogeneity of frictional properties

Nepal • Interseismic coupling • Analysis of temporal variations of seismicity and geodesy • Implications for EQs nucleation

Locked Fault Zone (Bollinger et al, 2004, Bettinelli et al, 2006) This model of interseismic strain (1995 -2005) indicates an accumulation rate of deficit of seismic moment of 4. 3 1019 Nm/yr Mw 7. 6 (2005 Kashmir EQ): 7 yr Mw 8. 2 (1934 Bihar-Nepal EQ): 100 yr

Seismicity and Coulomb stress change due to interseismic strain (Bollinger et al, JGR, 2004) 1. Seismicity coincides with the area where Coulomb stress increases by more than 4 k. Pa/yr. 2. The influence of topography on the seismicity distribution show that the deviatoric stresses driving deformation are actually low, less than about 35 MPa

Horizontal displacements relative to India SIM DAMA NAGA GUMB LHAS Seasonal variation of Horizontal Displacements (Bettinelli et al, 2008)

Seismicity is enhanced in the winter when shortening rate across the Himalayan is increased.

Amplitude of seasonal variations of surface loading derived from GRACE