Computational Seismology

sense do not grow as fast as computational possi­ This book contains selections from Volumes bilities. I-V of the series "Computational Seismology," which Moreover, for some strange reason, comput­ was initiated a few years ago by the Academy of ers usually create a spirit of haste, though they are Sciences of the USSR. Volume V was still in prepa­ intended to provide time for meditation. In com­ ration when the translation was begun, and the trans­ puterizing seismology, therefore, one must first lations of papers from it were made from manu­ generalize the methods and then make them more scripts. Most of the authors are members of the rigorous mathematically. All relevant data must Department of Computational Geophysics of the In­ be processed jointly. Insofar as is possible, a priori stitute of Physics of the Earth, Moscow. hypotheses should be avoided. Particular attention The series is dedicated to theoretical and must be given to exact formulation of the problem, computational aspects of the analysis of seismolog­ to questions of uniqueness and stability, to the con­ ical data. The present state of this field is typical fidence limits of the results, etc. This general ap­ of our times. The rapidly increasing flow of infor­ proach is required in solving the main problems of mation is already too vast to be processed or even modern seismology, which are by definition general comprehended in a traditional way. This has forced problems. This approach has other advantages.

Contenu

Introduction: Seismology and Logic.- I: Automation of Seismological Surveys.- Computer Determination of Earthquake Epicenters.- Computer Determination of Earthquake Focal Depth.- Automatic Identification of Seismic Wave Arrivals.- Computer Determination of Earthquake Mechanism.- II: Seismic Waves.- Some Problems of the Use of P-Wave Dynamics to Find the Velocity Profile of the Upper Mantle.- The Effect of Focal Depth in the Crust on the Wave Field in the Initial Part of a Seismogram.- Approximation of Velocity Distributions for Calculation of P-Wave Times and Amplitudes.- Amplitudes of Fundamental Seismic Waves in the Mantle.- Interference Head Waves.- Method for Calculating Surface Rayleigh Waves in a Vertically Inhomogeneous Half-Space.- Higher Modes of Rayleigh Waves and Upper Mantle Structure.- Surface-Wave Amplitude Spectra.- III. Inverse Problems of Seismology.- Inverse Problems of Seismology (Structural Review).- Determining Seismic Profiles from a Set of Observations.- Expediting Body Wave Calculations.- Determining Seismic-Wave Velocity from Travel-Time Curves.- Properties of Surface-Source Travel-Time Curves.- Characteristic Properties of Deep-Focus Travel-Time Curves.- Finding a Velocity Profile from a Love Wave Dispersion Curve: Problems of Uniqueness.- IV: Statistical Applications.- Effect of Station and Source Factors on the Accuracy of Seismic Parameter Determination.- A Statistical Method for Determining Earthquake Focal Depth from the Record of One Seismic Station.- Local Statistics of Earthquake Catalogs.