V. K. Balkhanov

Formation of circular rings on the snow-covered ice field of Lake Baikal

Satellite images taken from the ice surface of Lake Baikal show dark rings 7–8 km in diameter. Physically, this phenomenon can be explained by the emission of warm natural gas from the sedimentary thickness on the Lake Baikal bed. When the natural gas ascends toward the surface, it cools down but has time to heat ambient cold water. This gives rise to toroidal convection around the site of natural gas emission in the water column. Convection carries the warmed water to the surface (to the lower surface of ice) clear of the natural gas column. The heat reaches the upper surface of ice by means of heat conduction, where snow starts intensely melting. As a result, a thaw hole in the form of a ring arises on the snow-covered ice.

The Transmission and Reflection Coefficients of an Electromagnetic Wave for a Gradient Dielectric Layer

A gradient dielectric layer is considered. In the layer, permittivity ɛ(z) depends on coordinate z as follows: ɛ(z) = ɛLa4/(z − a)4 (a being the gradientness parameter). For this layer, reflection and transmission coefficients rr and rt are determined. It is found that, in a wide frequency range, the considered gradient layer has amplitude- and phase-constant reflection and transmission coefficients and can serve as a low-pass filter in radio devices involved in the transmission of wideband signals.

Spatial characteristics of radiation from lightning discharges

The results of measurements of levels of electric and magnetic radiation fields from lightning discharges are presented. Lightning discharges occurred in the region of the terrestrial surface bounded by a sector of ∼90° with a radius of ∼30–300 km. A power spatial dependence of the electromagnetic radiation field components of lightning discharges is established. The results of measurements are interpreted using fractal geometry methods.

Restoration of a two-layer geoelectric section in the coastal area of Lake Baikal

Radioimpedance measurements are taken at two sites on ice in the coastal area of Lake Baikal. From these full-scale measurements for a water-bottom soil system, a two-layer geoelectric section is restored; namely, the resistivities of a water layer and bottom soil are determined and the thickness of the water layer is measured. For example, the following values are obtained at one of the sites: water resistivity ρw = 120 Ω m, bottom soil resistivity ρb = 1400 Ω m, and depth h = 5.5 m. These values are in agreement with published data. The suggested method or geoelectric section restoration is applicable to a thin water layer near the coast.

Way of detecting an electromagnetic earthquake precursor

A way of detecting an electromagnetic earthquake precursor is suggested. Detection is carried out with a device composed of a vertical electrical antenna and a toroidal magnetic antenna located on the Earth’s surface. It is shown that the detector is the most sensitive to the radiation of an electrical dipole inside the lithosphere that is oriented normally to the Earth’s surface. Such a pattern allows one to detect electromagnetic precursors by the method suggested.

Characteristics of the electromagnetic wave field far away from the radiation source

A solution to the Sommerfeld problem of the far (in terms of wavelengths) field of a vertical electrical dipole placed at the interface between two media has been found. The characteristics of a surface electromagnetic wave that propagates over a medium with highly inductive surface impedance δ have been determined. The spatial characteristics of the wave are expressed through the real and imaginary parts of impedance δ. It has been proved that the surface electromagnetic wave is the major contributor to the electromagnetic field of the ground wave in the case of highly inductive radio paths.

Analogy between electric parameters of inhomogeneous media and geometrical characteristics of the fractal line

Analogy is established between the surface impedance modulus, frequency, and skin depth of inhomogeneous media on the one hand and the fractal line length, measurement scale, and the number of measurement scales required for measuring length, respectively, on the other hand. This analogy makes it possible to obtain frequency characteristics of the skin layer and the surface impedance modulus independently from other methods. The frequency characteristics satisfactorily describe sedimentary and crystalline rocks in a wide frequency range.

Frequency and spatial characteristics of the electrophysical parameters of a living tree trunk

AbstractThe method of vertical electrical sounding is applied to derive the spatial characteristic of the dc resistivity ρ of a living pine trunk, ρ = L-0.85, and the frequency characteristic of the ac resistance R of the same pine trunk, R = f-0.053. The results are simulated by the methods of fractal geometry, according to which ρ = L−h + 2 and

Deformation of freshwater ice cover measured by a horizontal electric antenna

R \sim f^{ - \tfrac{3} {h} + 1}