## Maxwell's equations for the Earth's electromagnetic fields of force and without it

Electromagnetic fields that are observed on the Earth with the worldwide network of magnetic observatories as well as regional means when surveying the Earth's interior are conventionally considered to be force and one-mode fields.

For the numerical modeling of electromagnetic fields observed on the Earth, a force component of Maxwell's...

## Modern electrodynamics for the Earth's physics

Electromagnetic methods for studying the Earth, electromagnetic techniques of geophysical prospecting, in particular, are conventionally based on the fact that any electromagnetic field, either observed on the Earth or artificially excited by generators, satisfy Maxwell's equations and is analytically described by these equations.

This opinion is so popular among geophysicists...

## The expert earthquake database (EEDB) for seismic-geodynamic research

In this paper, a high-tech expert system EEDB for solving a wide range of seismological research tasks is proposed. The logical and functional structure as well as results of the algorithms usage for the analysis of seismic processes are considered. The algorithms allow us to calculate and to visualize maps...

## Planning seismic networks in the Kemerovo region

Seismic observations in the Altai-Sayansk region, one of seismic-prone zones in Russia, are a part of the federal observations over natural and man-caused factors. The territory of the region in question makes more than 1.5 ∙ 106 km2 includes 13 subjects of the Russian Federation and three border areas...

## About one form of the dynamic equation of porous media in terms of velocities, stresses, and pressure

The form of the equation of motion of porous media in terms of velocities, stresses and pressure as a symmetric t-hyperbolic system has been obtained.

## Spherical mean value theorem for a poroelastic static system

Mean value relations for a vector of displacement of an elastic porous body and a pore pressure for a poroelastic static system, when mass forces and energy dissipation are absent, are obtained.

## Algorithms and methods for the numerical simulation of seismic wave fields in cavernous zones

A developed toolkit (parallel programs and visualization tools) for the numerical simulation of the elastic wave propagation in 3D and 2D nonhomogeneous elastic media, comprising cavernous inclusions applicable to the on-site inspection, is described. According to the results obtained, groups of waves were identified, and synthetic data reflecting the influence...

## Catalog and database on the Earth impact structures

An Expert Database on the Earth Impact Structures (EDEIS) has been compiled and is being maintained in the Tsunami Laboratory of the Institute of Computational Mathematics and Mathematical Geophysics of SB RAS in Novosibirsk. The database has been developed on the basis of the catalog of Earth impact structures that...

## A new method for determination of a wave-ray trace based on tsunami isochrones

A new method for the tsunami wave ray construction is proposed. It is based on isochrones that are built with the use of the wave travel times to a tsunami source. The wave ray approximation is determined as a broken line passing through intersection points of identical time isochrones from...

## Directivity of tsunami generated by subduction zone sources

In a subduction zone, a tsunami source is usually situated above the continental bottom slope. Due to the wave refraction, the opposite slope of a deep water trench works like an optical lens for tsunami waves. The tsunami propagation process is studied using the wave-ray approximation. The tsunami amplitude reduction...

## Some analytical solutions for tsunami wave rays and front

Methods for computing wave kinematics are wide-spread for studying the wave propagation in non-homogeneous media. Exact analytical solutions for nontrivial media are needed for testing such methods. The formula describing the wave-front shape has been found for some media with a power dependence of conductivity on only one spatial coordinate....

## General laws of spatial-temp oral distribution of the Earth's impact structures

A brief review of the author's catalog of the Earth's Impact structures, presented on the site of ICM&MG, is given in this paper. For the research into general laws of distribution with space of the impact structures compiling the catalog and for the analysis of their parameters it is offered...

## Inverse algorithm for recovering a tsunami source using truncated SVD

The inverse problem to infer the initial water displacement is treated as an ill-posed problem of the hydrodynamic inversion of tsunami tide gauge records. To this end, we have developed a technique based on the least square inversion and a truncated SVD approach. The proposed filtering technique essentially improves the...