5:36 PM - 4:39 PM
[SCG62-P10] Detection and mechanism determination of VLF earthquakes in the Guerrero subduction zone
3-min talk in an oral session
MASE experiment data from 2005 to 2007 are used to determine the location of tremors and VLF earthquakes. They are found in two places tremors are detected, the southern transient cluster and the northern, more persistent, cluster. Both are located near the flat part of the subduction interface. This seems to confirm that VLF earthquakes are produced by shear failure near this interface. The VLF signals are then inverted to estimate the moment tensor of these events. Due to the linear geometry of the MASE experiment the mechanism is not well constrained but one of the nodal plane is generally nearly horizontal in accordance with the distinctive geometry of the subduction and the slip direction is globally coherent with the convergence direction. Moreover, the plunge of the P and T axis are well constrained with values of about 40⁰adding a constraint on the principal stress directions.