investigating earthquakes nucleation from the resposne of himalayan seismicity to the monsoon...
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DESCRIPTIONTIBETINDIA GPS LOADING OF THE INDIAN PLATE DUE TO THE MONSOON NEPAL earthquakes
Investigating earthquakes nucleation from the resposne of Himalayan seismicity to the Monsoon
Thomas ADER, Kristel Chanard
Nadia LAPUSTA, and Jean-Philippe AVOUAC
December 9, 2011
Secular/constant loading rate
Sudden stress change due to a main earthquake: mainshock/aftershock sequences
Here: periodic stresses on the Main Himalayan Fault, underneath Nepal.
The study of earthquake triggering allows testing models of earthquake nucleation
LOADING OF THE INDIAN PLATE
DUE TO THE MONSOON
Modified from Bettinelli et al. (2008)
Montrer la serie GPS avec la prediction du modele de Kristel
Also periodic stress due to tides
2 stresses with roughly the same amplitude (~3kPa) but different periods but
No correlation of seismicity with tidal stress Correlation with hydrological cycle (Monsoon)
Nucleation is time dependent. Nucleation predicted by rate-and-state friction on finite size faults can explain our observationsThe characteristic time for earthquake nucleation (hence faults frictional properties) can be assessed: long enough so that the response to earth tides (12h) is damped short that enough seismicity response to seasonal variations of stress.
IMPLICATIONS FOR NUCLEATION