The selected sequences had optimal station coverage, short distance to the stations and short hypocentral
distance between events.
Previous determinations of hypocentral
parameters ignore historical data from previous seismic events and instead use only information recorded during current earthquakes.
Where r is a vector of travel time residuals with dimension L (= MA-N) dh is a vector of hypocentral
parameters adjustment with dimension 4N and dU is a vector of slowness parameter adjustments having dimension P and B denote an LA-4N matrix related to the derivatives of travel times with respect to hypocentral
location of the AE multiplets in the Basel data set identified at low and high frequencies is determined by double difference (DD), one of the high-resolution relative mapping techniques .
Este metodo se basa en la consideracion de que la distancia hypocentral
entre dos sismos localizados en una misma estacion es pequena comparada con la distancia eventos sismico - estacion y la heterogeneidad de la velocidad; entonces el camino del rayo entre la fuente simica y una estacion comun es similar a lo largo del rayo.
Both events had hypocentral
depths of approximately three miles, similar magnitudes (a duration magnitude 2.
Based on these coordinates and coordinates of underground seismic stations one can calculate the hypocentral
distance between the focus and the respective site of observation.
Effect of inaccurate assumption Vp velocity of 200 m/s deviation of average value Vp = 3800 m/s, could cause at hypocentral
distance of 1000 m the error of 53 m.
locations of the aftershocks were determined with the help of computer code HYPO71PC (Lee, 1990) using body wave data recorded by local seismic network.
Aftershock characteristics give clues regarding the nature of the relatively long-term processes redistributing stress following instantaneous stress changes associated with a mainshock (Wesson, 1987) It seems likely that this was responsible for the concentration of stress in the hypocentral
region of the largest 1993 aftershocks prior to and resulting in the nucleation of the 1995 mainshock Such systematic northward migration led to suggesting an initial model for earthquake migration in the Gulf of Aqaba (Figure 6), although real migration would likely have been more complicated However, the largest aftershock's epicentre in this model represented the stresses nucleation area and location of the next large mainshock (Figure 6)
Again, estimates for the hypocentral
depth indicate faulting within the upper crust (Fig.
3B), recorded at hypocentral
distances of < 150 km (81.