On the basis of several seismograms should be set the time and place of the earthquake. It will be a case of " close " earthquake allow some simplification. As part of the introduction to the exercise, will be presented the basics of propagation of longitudinal (P) and shear (S) seismic waves, and the method of Wadati spheres to obtain an earthquake location. The task will be to identify the P and S waves on seismograms, to pick their onset time, to determine a time t0, and to locate an earthquake for the known geometry of positions of seismic stations. Base variant will be based on synthetic data ("no errors") gives the possibility to verify the result with the known location of the source. Extended variant will be based on actual recorded data of an earthquake from seismic catalog. In this case, the comparison will be done with the catalog information, obtained as a result of routine seismological studies by professionals. In both variants a person performing the exercise will have an invention to analyze the errors of calculation of time of the earthquake, the epicenter and the depth of the source. Lecturer: Prof. Marek Grad (mgrad@mimuw.edu.pl) |
