The study is focused on the effect of transient external force induced by a passing seismic wave on fault motion in different creep regimes. Displacement along the fault is represented by the movement of a spring-block model, whereby the uniform and oscillatory motion correspond to the fault dynamics in post-seismic and inter-seismic creep regime, respectively. The effect of the external force ...

The seismic behaviour of underground structures is generally satisfactory compared to the above-ground ones. However, despite of the buried structure confinement, in recent strong seismic events some underground structure as tunnels, pipelines and tanks suffered high damage; for this reason, a strong effort is focused to evaluate the seismic vulnerability of these structure and to give codes in...

PURPOSE To investigate the patterns of immediate seismic deaths and post-earthquake mortality changes in the disaster area after the September 21, 1999 Taiwan earthquake. METHODS We used the data of 1826 seismic deaths to elucidate the immediate seismic effects on mortality patterns, and to determine the association between seismic death rates and house damage among 23 townships in the disast...

An overview of Gaussian beam imaging is given for converted and surface reflected seismic waves. The earthquake seismology community now regularly uses seismic waves from distant sources to illuminate structures beneath seismic arrays in so-called passive imaging experiments. Similarly, reservoir structures can be imaged with seismic waves incident from below using sources in boreholes. Gaussia...

Seismic anisotropy has been widely observed in crust and mantle materials and plays a key role in the understanding of structure and flow patterns. Although seismic anisotropy can be explained by the crystal preferred orientation (CPO) of highly anisotropic minerals in the crust, that is, amphibole, experimental studies on the CPO of amphibole are limited. Here we present the results of novel e...

[1] A single plane fracture with an axially symmetric stress distribution behaves as a seismic lens that focuses seismic energy to a beam ‘‘waist’’ at a focal plane. Both phase and amplitude effects on a seismic wave propagating across the fracture contribute to the lensing behavior. Radial gradients in the fracture specific stiffness cause wave refraction through a radially varying group time ...

Seismic signals generated by artificially released avalanches were studied f’rom the seismological viewpoint in the time and frequency domains in an attempt to characterise them for monitoring purposes. The avalanches were artificially released and the corresponding seismic signals were recorded at different sites within a radius of up to 3 km together with the video images with a common time r...

The seismic microzonation evaluate the seismic hazard at the local scale proposing to identify areas of territory characterized by homogeneous seismic behaviors. The first level of seismic microzoning has the purpose of defining the lithological properties and geometry of geological units that characterize these portions of territory (microzones). The scope of this work is to contribute to the ...

The teleseismic transmission of seismic surface waves from earthquakes results in a loss of the high frequencies needed to infer information about Earth’s crust and uppermost mantle. A recent innovation in seismic imaging based on using long time sequences of ambient seismic noise moves beyond some of the limitations imposed on earthquakebased methods to reveal high resolution information about...

[1] The Thurwieser landslide that occurred in Italy in 2004 and the seismic waves it generated have been simulated and compared to the seismic signal recorded a few tens of kilometers from the landslide source (i.e., landquake). The main features of the low frequency seismic signal are reproduced by the simulation. Topography effects on the flowing mass have a major impact on the generated seis...