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. Although earthquake early warning systems have inherently short warning times between seconds and a minute they become increasingly important as part of real time information systems that can be designed to support disaster management in earthquake prone areas. In some cases (Mexico City, Bucharest) the hazardous earthquakes are bound to a rather distant tectonic unit so that a fairly large warning...
. The spatial distribution of the resonance frequency of the sedimentary cover in the Cologne area was estimated by the horizontal-to-vertical spectral ratio method using ambient noise measurements. A comparison with the eigenfrequencies of selected long-span bridges crossing the Rhine river indicated an overlap in frequency and therefore potential damage in the case of an earthquake. Consequently,...
. Four possible scenarios of the 1927 Jericho earthquake are tested by simulating 75 seconds of 1.5 Hz-wave propagation in a 3D model of the Dead Sea Basin (DSB) substructure. The scenarios examine the effects of various source and rupture parameters, since the original parameters could not be constrained by the sparse data gathered in 1927. The simulations are carried out using a fourth-order staggered-grid...
. Nonlinear effects in ground motion during large earthquakes have been a long controversial issue between seismologists and geotechnical engineers. Laboratory tests made by using resonant columns consistently show the reduction in shear modulus (G) and increase in damping ratio (D) with increasing shear strain ($\gamma$), i.e., G = G($\gamma$), respectively, D = D($\gamma$). Therefore nonlinear viscoelastic...
. Columnar, upwelling masses of hot rock in the Earth’s mantle, called mantle plumes, are spectacular features of our planet because they supply the melts for the major intraplate volcanic sites. Although geodynamic modelling provides some constraints on the geometrical, physical, and fluid-dynamic properties of mantle plumes, there are still many uncertainties concerning the nature of mantle plumes,...
. From 1968 until 1990, Russian scientists carried out an intensive program of deep seismic sounding across the territory of the former Soviet Union, using Peaceful Nuclear Explosions (PNEs) as powerful sources for elastic waves. The explosions, both chemical and nuclear, were recorded by up to 400 shot-period (1-2 Hz) three-component, analog recording systems. The average station spacing of about...
. Kirchhoff migration is a well-known process in the world of seismic exploration to transform seismic reflection data into an interpretable image of the subsurface. In former times, only kinematic traveltime information were utilized to image interfaces within the earth. That means, the dynamic information related to the recorded amplitudes remained unused. During the last decades, migration concepts...
. Geophysical exploration for volcanogenic massive sulphide (VMS) deposits, a major source for lead, copper, zinc and other metals, is conventionally done using magnetic and electromagnetic methods. For small deposits at depths greater than about 500 m, where these methods are no longer applicable, vertical seismic profiling (VSP) methods are a potential alternative, when a borehole exists in the...
. The Dead Sea fault (DSF) is the most impressive tectonic feature in the Middle East. It is a plate boundary, which transfers sea floor spreading in the Red Sea to the Taurus collision zone in Turkey. The DSF has influenced many aspects of this region, including seismicity and ground water availability. It may have even affected the course of human evolution. Numerous geophysical and geological...
. In order to investigate the geodynamic processes and rheological parameters, which are principally responsible for the observed surface deformation, a three-dimensional finite element model of the Eastern Mediterranean was built up. The northward movement of the Arabian and the African plate relative to the Eurasian plate has been assumed to control the tectonic evolution of the Aegean-Anatolian...
. Detachment of descending oceanic lithosphere (slab) is considered to be an important geodynamic process returning lithospheric material into the deeper mantle. On the geological time scale the detachment process itself is a short-term procedure. Thus it can be studied only at a few localities on Earth today. The Vrancea region in the SE-Carpathians is one of these rare places. In the SE-Carpathians,...
. Recent findings from regional seismic tomography and refraction studies and from GPS studies on vertical movements together with extremely high intermediate-depth seismicity in the Vrancea region (Romania) point towards the interpretation that the lithospheric slab, descending beneath the SE-Carpathians, approaches a stage of break-off or even it is already delaminated from the crust. To understand...
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