Seismic ambient noise of surface wave tomography was applied to estimate Rayleigh wave empirical Green＇s functions （EGFs） and then to study crust and uppermost mantle structure beneath the Makran region in south-ea...Seismic ambient noise of surface wave tomography was applied to estimate Rayleigh wave empirical Green＇s functions （EGFs） and then to study crust and uppermost mantle structure beneath the Makran region in south-east 1mn. 12 months of continuous data from January 2009 through January 2010, recorded at broadband seismic stations, were analyzed. Group velocities of the fundamental mode Rayleigh wave dispersion curves were obtained from the empirical Green＇s functions. Multiple- filter analysis was used to plot group velocity variations at periods from 10 to 50 s. Using group velocity dispersion curves, 1-D Vs velocity models were calculated between several station pairs. The final results demonstrate signifi- cant agreement to known geological and tectonic features. Our tomography maps display low-velocity anomaly with SW-NE trend, comparable with volcanic arc settings of the Makran region which may be attributable to the geometry of Arabian Plate subducting beneath the overriding the Lut block. The northward subducting Arabian Plate is deter- mined by high-velocity anomaly along the Straits of Hor- muz. At short periods （〈20 s）, there is a sharp transition boundary between low- and high-velocity transition zone with the NW trending at the western edge of Makran which is attributable to the Minab fault system.展开更多
文摘Seismic ambient noise of surface wave tomography was applied to estimate Rayleigh wave empirical Green＇s functions （EGFs） and then to study crust and uppermost mantle structure beneath the Makran region in south-east 1mn. 12 months of continuous data from January 2009 through January 2010, recorded at broadband seismic stations, were analyzed. Group velocities of the fundamental mode Rayleigh wave dispersion curves were obtained from the empirical Green＇s functions. Multiple- filter analysis was used to plot group velocity variations at periods from 10 to 50 s. Using group velocity dispersion curves, 1-D Vs velocity models were calculated between several station pairs. The final results demonstrate signifi- cant agreement to known geological and tectonic features. Our tomography maps display low-velocity anomaly with SW-NE trend, comparable with volcanic arc settings of the Makran region which may be attributable to the geometry of Arabian Plate subducting beneath the overriding the Lut block. The northward subducting Arabian Plate is deter- mined by high-velocity anomaly along the Straits of Hor- muz. At short periods （〈20 s）, there is a sharp transition boundary between low- and high-velocity transition zone with the NW trending at the western edge of Makran which is attributable to the Minab fault system.
