Seismic Velocity Model of P- and S-waves for the Italian Lithosphere

<p>P- and S- seismic waves 3D velocity model of the Italian Lithosphere obtained by linearized seismic local earthquake tomography (LET) method by <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/92JB00603">Zhao et al., 1992</a>.</p> <p>The inversion for the model parameters is performed using a combination of pseudo-bending and Snell&#39;s Law for ray tracing on a 3D grid of nodes on spherical coordinates and the LSQR algorithm by <a href="https://dl.acm.org/doi/10.1145/355984.355989">Page and Saunders, 1982</a>. The method allows to model first order seismic discontinuities like the Moho, for which the Moho for the Italian region by <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2011GC003649">Di Stefano et al., 2011</a>.</p> <p>A previous version of the same tomographic inversion was produced and discussed in <a href="https://www.sciencedirect.com/science/article/abs/pii/S0264370714001306?via%3Dihub">Di Stefano and Ciaccio, 2014</a> but not released in digital file format.</p> <p>The present file is an updated version&nbsp;of the model by&nbsp;<a href="https://www.sciencedirect.com/science/article/abs/pii/S0264370714001306?via%3Dihub">Di Stefano and Ciaccio, 2014</a>, based on a slightly different gridding but with the same P- and S- travel-times and earthquakes locations dataset.</p> <p>The model is here released&nbsp;in&nbsp;csv, pipe (|) separated, file.</p> <p><strong>Header Explanation</strong></p> <ul> <li><strong>lon</strong>: longitude in decimal degrees positive eastward from&nbsp;Greenwich</li> <li><strong>lat</strong>: latitude in decimal degrees positive northward</li> <li><strong>depth</strong>: depth in km positive downward</li> <li><strong>type</strong>: type of model parameter (vp= P-wave velocity; vs= S-wave velocity)</li> <li><strong>value</strong>: seismic velocity value</li> <li><strong>units</strong>: units measure of the velocity value</li> </ul> <p>The external bounding box of the model is:</p> <ul> <li>Minimum Longitude = 5&deg;E</li> <li>Maximum Longitude = 20&deg;E</li> <li>Minimum Latitude = 36&deg;N</li> <li>Maximum Latitude = 48&deg;N</li> <li>Minumum Depth = 0 km</li> <li>Maximum Depth = 80 km</li> </ul> <p>Lines 2 to&nbsp;43093 report the Vp model</p> <p>Lines&nbsp;43094 to&nbsp;86185 report the Vs model</p>