With the present study we introduce a fast and robust method to calculate source displacement spectra of small earthquakes on local regional scale. The work is based publicly available Qopen full envelope inversion which further tuned for given purpose. Important parameters -- seismic moment, moment magnitude, corner frequency high-frequency fall-off are determined from by fitting simple earthq...

[1] We study stress levels and radiated energy to infer the rupture characteristics and scaling relationships of aftershocks and other southern California earthquakes. We use empirical Green functions to obtain source time functions for 47 of the larger (M 4.0) aftershocks of the 1994 Northridge, California earthquake (M6.7). We estimate static and dynamic stress drops from the source time func...

Attempts to build a “constant-stressdrop” scaling of an earthquake-source spectrum have invariably met with difficulties. Physically, such a scaling would mean that the low-frequency content of the spectrum would control the highfrequency one, reducing the number of the parameters governing the time history of a shear dislocation to one. This is technically achieved through relationships of the...

Short-period (SP) and long-period (LP) seismograms written by the main shock and two principal aftershocks of the 1976 Friuli, Italy, earthquake sequence are modeled in the t ime domain using synthetic seismograms. The main shock occurred on 6 May 1976 (20h OOm, Ms = 6.5) and both aftershocks on 15 September 1976 (03h 15m, Ms -6.0 and 09h 21m, Ms = 5 .9 ) , Source models were determined init ia...

The conventional magnitude scale M suffers saturation when the rupture dimension of the earthquake exceeds the wavelength of the seismic waves used for the magnitude determination (usually 5-50 km). This saturation leads to an inaccurate estimate of energy released in great earthquakes. To circumvent his problem the strain energy drop W (difference in strain energy before and after an earthquak...

Seismic moment and rupture length can be combined to infer stress drop, a key parameter for assessing earthquakes. In natural earthquakes, drops are largely depth-independent, which is surprising given the expected dependence of frictional on normal stresses hence overburden. We have developed transparent experimental fault that allows direct observation thousands slip events, with ruptures ful...

The behaviour of viscoplastic drops during formation and detachment from a capillary nozzle, free-fall, impact on a solid substrate and subsequent spreading are investigated experimentally by high-speed imaging. Drop dynamic behaviour is an integral component of many contemporary industrial processes ranging from fuelinjection systems in combustion engines to spray coating, agrochemical and pha...