Fluctuations of total electron content in the ionosphere as deduced from measurements by single-frequency GPS receivers

Using an ionospheric diagnostic technique developed by the authors and single-frequency GPS receivers, we obtained the first results of these diagnostics. In particular, we show that the ionosphere is characterized by large-scale periodic processes with frequencies of 3–5 mHz.     

Map of Anthropogenic Soil Erosion of Russia

Doklady Earth Sciences - The last map of anthropogenic soil erosion in Russia was compiled more than 20 years ago on a scale of 1 : 5 000 000. In recent years, additional data on soil...     

Deep-towed side-scan survey of the United Nations Rise, eastern Mediterranean

 A newly discovered area of mud volcanism, about 170 km south of Crete, in the central–eastern part of the Mediterranean Ridge, was named the “United Nations Rise” (UNR). A survey of the UNR area with the deep-towed ORE tech side-scan sonar equipped with a subbottom profiler revealed the presence of some mud volcanoes and also showed various other sea-floor features, including slumps, escarpments and pockmark-type depressions. Several of our interpretations were ground-truthed by coring. The UNR area appears to belong to the Inner deformation front of the Mediterranean Ridge.     

The Relationship among Geodynamics,Heat Flow,Deep Structure,and the Oil and Gas Potential of Yamal

Doklady Earth Sciences - The amount of hydrocarbon deposits per unit area of Yamal Peninsula is more than 100 times as much as the global average. The hydrocarbon deposits are generally situated in...     

Mineralogical–Geochemical Types and 190Pt–4He Age of Ferroan Platinum of Placers of the Anabar River Basin,Northeastern Part of the Siberian Platform

Doklady Earth Sciences - Typical features of platinum group minerals (PGMs) and the results of 190Pt–4He dating of the Fe–Pt solid solutions are presented for complex...     

Estimation of the effective recombination coefficient by variations in the maximum usable frequencies of one-hop high-frequency radio lines during the solar eclipses of March 29, 2006, and August 1, 2008

This paper presents the results of experimental investigations of variations in maximal usable frequencies (MUFs) during solar eclipses with the use of the method of panoramic tilt sounding by chirps in Eastern Europe and Western Siberia. The characteristics of perturbations of MUFs have been obtained experimentally. It has been established that the effective recombination coefficient increases by 24% in the ionospheric F region with an increase in the maximum eclipse phase from 0.49 to 1.0.     

Characterization of oil pollution around the oil rocks production site in the Caspian Sea using spaceborne polarimetric SAR imagery

Based on the processing and analysis of radar imagery received by the Radarsat-2 satellite in summer 2009 over the Oil Rocks (Neftyanyye Kamni or Neft Dashlari) oil production site in the Caspian Sea, it is shown that the images are full-fledged products, making it possible to retrieve information on the oil pollution and, under certain assumptions, estimate volumes of industrial oil spills. To map the space-time distribution of oil patches, the wide-swath mode of the Radarsat-2 synthetic aperture radar (SAR) with vertical VV polarization of signal is most suitable. The polarimetric regime itself does not improve the identification of oil pollution. The special quad-polarization mode in these experiments has not showed substantial advantages; the maximum contrasts were observed at vertical polarization. Estimates of oil spills volumes are obtained.     

The possibilities of paleomagnetic and geohistorical analyses of “tiny wiggles” short-period marine magnetic anomalies

Marine magnetic anomalies of the tiny wiggles (TW) type can be used to solve geohistorical and paleomagnetic problems. The model fields corresponding to Paleocene–Eocene anomalies in the northwestern Indian Ocean, which were formed during the fast-spreading stage, were studied. For these fields, widely used interpretation methods were compared with a method proposed previously by the authors. The testing was performed with first the classical block model and then more complex models reflecting actual processes of oceanic accretion and magnetic field variations in the past. It was shown that the proposed method has advantages for this problem; it gives an error close to the minimum possible error and can adequately be used in interpretations. Spectral and statistical methods are used to estimate the magnetic anomaly resolving power and to study some factors that can exert a distorting influence. In addition, model examples have been used to indicate how the TW determination accuracy is affected by diurnal variations in the main magnetic field (MMF) and by ancient magnetization vector determination errors.