GNGTS 2022 - Atti del 40° Convegno Nazionale

140 GNGTS 2022 Sessione 1.3 floodplain, representing the fault bending of the SFT belt 30 km east of its surface exposure. These observations document the seismic potential of blind ramps and axial surfaces in fold- and-thrust belts and the control on final rupture size by fault bends and surrounding folds. Methodology. For radar image formation and post-processing, we use GMT5SAR (Sandwell et al. , 2011). The ascending and descending interferograms show line-of-sight displacements of approximately 45 and 50 mm, respectively. In a preliminary step, we estimate the simplified source parameters assuming coseismic rupture on a single fault plane, ignoring potential folding in the hanging wall. We constrain the dip, strike, depth, width, length, rake, and slip based on data from both interferograms using a Monte Carlo method for a rectangular patch of uniform slip (Bagnardi and Hooper, 2018). We determine the parameter uncertainties based on the semi-variograms of the interferograms. The seismic moment M o = 3.94× 10 17 Nm, assuming a shear modulus of 32 GPa, is calculated using the mean value of the probability distribution Fig. 2 - Finite kinematic models of the Mw5.7 Dajal earthquake on two-end member fault and fold geometry. a) Co-seismic slip distribution on the decollement-ramp-decollement system and associated flexural slip on two axial surfaces. b) Predicted line-of-sight (LOS) displacement for the ascending interferogram. c) Residuals with InSAR data. d) Predicted LOS displacement for the descending interferogram and e) associated residuals. f) Distribution of slip on the decollement-ramp system and associated flexural slip on the axial surface. g) Predicted LOS displacement for the ascending interferogram and h) corresponding residuals. i) LIS model for the descending interferogram and j) residuals.