Induced Deformations of Fault Zones

Izvestiya, Physics of the Solid Earth - Empirical data obtained by studying the Earth’s surface deformations in the fault zones induced by exogenous, endogenous, and manmade processes are...     

Inclinometric Observations at the Korchagin Deposit

Izvestiya, Atmospheric and Oceanic Physics - The aim of this work is to analyze the results of geodeformation monitoring at the Korchagin oil, gas, and condensate deposit in the Caspian Sea. The...     

Remnant Massifs of Layered Deposits at High Northern Latitudes of Mars

Ice deposits of the permanent northern polar cap of Mars exhibit a clearly expressed layered structure connected with consecutive accumulation of a solid phase of H₂O (ice) with different impurity fractions of dust. The observed structure of the northern polar cap deposits is direct evidence of the uneven accumulation of ice associated with climate variations on Mars over a long period of time. Outside the boundaries of the present northern polar cap, there are isolated remnant massifs of bright deposits with a clearly distinguishable layered structure. In this paper, we analyze the morphology, spatial distribution, and material composition of remnant massifs within the latitude belt of 60°–85°. The similarity in the structure and material composition found in the remnant massifs and the layered deposits of the northern polar cap of Mars apparently suggests that these formations were genetically connected in the past climatic epochs.     

Grouping Small Spacecraft for Global Meteorological Observations Using a Microwave Radiometer–Spectrometer

Izvestiya, Atmospheric and Oceanic Physics - The current state of microwave radiometry for remote sensing of the Earth is considered. There are currently some 30 satellite microwave radiometers...     

Dependence of sand soil compressibility on soil physical properties

A relationship between soil physical properties and its compressibility has been analyzed.The formulae to determine soil density and porosity have been substantiated in compression tests.The regularity of changes in compressibility of thawed sand soils with various degrees of water content has been experimentally identified.     

Late Paleozoic and Early Mesozoic rare-metal magmatism of Central Asia: Stages, provinces, and formation settings

Late Paleozoic and Early Mesozoic epochs in the formation history of the Central Asian Foldbelt are distinguished by high rare-metal productivity. A number of large REE, Ta, Nb, Zr, Be, Sn, Li, Mo, Re, and other deposits were formed at that time. As a rule, they are of the magmatic origin and related to the intrusions of highly evolved igneous rocks varying in composition from alkaline ultramafic with carbonatites to alkali and Li-F granites. In general, the occurrences of rare-metal magmatism are related to the rift zones of the Central Asian Rift System formed 310?C190 Ma ago and conjugated with a consecutive series of the Barguzin, Hangay, and Hentiy zonal igneous provinces characterized by the large batholiths in their centers and rift zones in the framework. Such a structure indicates that these provinces were formed above isometric mantle sources or plumes with participation of large-scale crustal anatexis. The evident links of rare-metal deposits to occurrences of mantle magmatism within the zonal igneous provinces show that plume sources played an important role in their formation.     

Geodynamical Evolution of the Earth’s Crust of Central Asia and Recent Geodynamics of the Kopet Dag Region,Turkmenistan

Izvestiya, Physics of the Solid Earth - Abstract—Current problems of combining the results of mathematical modeling for the geodynamical evolution of the Earth’s crust in Central Asia...     

Neutron generation and geomagnetic disturbances in connection with the Chilean earthquake of February 27, 2010 and a volcanic eruption in Iceland in March–April 2010

The relationship between solar and geomagnetic activities in connection with seismicity and volcanic eruptions on the globe during the period 1680–2010 is studied. The centennial cycles of terrestrial endogenous activity, related to solar and geomagnetic activity, are revealed; at the beginning of these cycles, solar cycles with small Wolf numbers were detected, while intensive seismic and volcanic activity was observed for several decades. A stable negative correlation between seismicity and volcanism, on the one hand, and solar and geomagnetic activity, on the other hand, were found. Experiments, which were simultaneously carried out at the Pushkov Institute of Geomagnetism, Ionosphere, and Radiowave Propagation, Russian Academy of Sciences (IZMIRAN), Troitsk, Moscow oblast, and the Karymshina Complex Geophysical Observatory, Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences, have verified the suggestion that disturbances in the geomagnetic field and neutron generation occur during the early stages of strong earthquakes. It is supposed that the mechanism of primary generation of terrestrial neutrons is related to nuclear reactions in the Earth’s interior.     

Giant pulses from the millisecond pulsar PSR B1937+214

We have detected giant pulses from the millisecond pulsar PSR B1937+214 at the lowest frequency of 112 MHz. The observed flux density at the pulse peak is ～40 000 Jy, which exceeds the average level by a factor of 600. Pulses of such intensity occur about once per 300 000 periods. The brightness temperature of the observed giant pulses is T _B≈10³⁵ K. We estimated the pulse broadening by interstellar scattering to be τ_sc=3–10 ms. Based on this estimate and on published high-frequency measurements of this parameter, we determined the frequency dependence of the pulse broadening by scattering: τ_sc(f)=25 × (f/100)^?4.0±02.     

Space shuttle observations of terrestrial impact structures using SIR‐C and X‐SAR radars

Abstract— Ten terrestrial impact structures were imaged during two flights of the 1994 space radar laboratory (SRL) experiment. These craters include Wolf Creek, Australia; Roter Kamm, Namibia; Zhamanshin, Kazakhstan; BP and Oasis, Libya; Aorounga, Chad; Amguid, Algeria; and Spider, Connolly Basin and Henbury, Australia. SRL contained two co‐registered instruments; the United States shuttle imaging radar‐C (SIR‐C) polarimetric radar system operating in L‐band (λ = 24 cm) and C‐band (λ = 5.6 cm), and the joint German/Italian synthetic aperture radar (X‐SAR) operating in vertically‐polarized X‐band (λ = 3 cm). Comparisons show SRL images to be complementary to, or in some cases superior to, corresponding optical images for evaluating size, location, and relative age of impact features. Regardless of wavelength or polarization, craters with significant relief appear prominently on radar as a result of slope and roughness effects. In desert regions, longer wavelengths penetrate dry sand mantles to reveal hidden crater dimensions or associated buried landforms. Radar polarities and wavelengths are particularly sensitive to vegetation, surface roughness, and soil moisture or electrical properties. In the more temperate environments of Kazakhstan and Australia, SRL images show detailed stream patterns that reveal the location and structure of otherwise obscured impact features.