Venus: Preliminary prediction of the mineral composition of surface rocks

A thermodynamical analysis of the multicomponent system SiTiAlFeMnMgCaNaKPCHO open with respect to CO₂, CO, H₂O was carried out. Hydration and carbonatization processes are proposed to be geochemical consequences of the hypothesis of quasi-equilibrium conditions between the troposphere and crustal surface rocks. The probable rock-forming hydrated mineral phases are represented by epidote, glaucophane, tremolite, phlogopite, and annite; the carbonatization results in existence of calcite and dolomite as rock-forming minerals of weathered alkaline lavas. The surface rocks are assumed to have high ferric/ferrous iron ratios. The wollastonite equilibrium is rejected as a buffering chemical reaction. Hydrated minerals could be stable at least up to 5-km depths and contribute about 0.1 × 10²⁴ g of H₂O whereas about (0.7–0.8) × 10²⁴ g of H₂O would be consumed in ferrous iron oxidation with concomitant hydrogen dissipation. The distribution of H₂O in the outer planetary shells is possibly a function of their temperatures.     

“Invisible” Gold in Pyrite and Arsenopyrite from The Pavlik Deposit (Northeastern Russia)

Doklady Earth Sciences - The first study on the distribution pattern and features of the “invisible” gold concentration in pyrite and arsenopyrite was carried out for a typical...     

Features of Ore Formation of Gold Deposits of the Glukharinskii Ore Cluster (Cis-Kolyma Terrain)

Doklady Earth Sciences - This paper reports on new data on δ34S and δ18O isotopy for trace and rare-earth elements of the Au deposits of the Glukharinskii ore cluster. The geochemical...     

Use of data of satellite system for gravity recovery and climate experiment (GRACE) for studying and assessment of hydrological-geohydrological characteristics of large river basins

Analysis is given of a relatively new method for studying the distribution and dynamics of land water resources, which is based on measuring the anomalies of Earth gravity field with the use of GRACE satellite system. The international satellite experiment on determining the gravity and climate changes has been carried out since 2002 with the aim of making high-frequency (within the frequency range of 10900?C36000 GHz) measurements of time variations in Earth??s gravity field. The measurement method and the procedure of data processing and evaluating the hydrological-geohydrological characteristics of large river basins and regions based on GRACE data.     

Klimovskaya: A new geomagnetic observatory

In 2011 Geophysical Center RAS (GC RAS) began to deploy the Klimovskaya geomagnetic observatory in the south of Arkhangelsk region on the territory of the Institute of Physiology of Natural Adaptations, Ural Branch, Russian Academy of Sciences (IPNA UB RAS). The construction works followed the complex of preparatory measures taken in order to confirm that the observatory can be constructed on this territory and to select the optimal configuration of observatory structures. The observatory equipping stages are described in detail, the technological and design solutions are described, and the first results of the registered data quality control are presented. It has been concluded that Klimovskaya observatory can be included in INTERMAGNET network. The observatory can be used to monitor and estimate geomagnetic activity, because it is located at high latitudes and provides data in a timely manner to the scientific community via the web-site of the Russian–Ukrainian Geomagnetic Data Center. The role of ground observatories such as Klimovskaya remains critical for long-term observations of secular variation and for complex monitoring of the geomagnetic field in combination with low-orbiting satellite data.     

Possibility of investigation of the microstreams and associations by the radiotomographic method

This article contains the tomographic problem's solution of the radiants distribution study by the meteor radar data. It was received the distribution of meteors velocities for the parts of celestial sphere with angular dimensions 10° × 10° and 1° × 1°. Was shown that the angular dimensions of most of radiants are equal 1° – 3° and larger part of the sporadic background looks like a totality of microstreams.     

Rutile Enriched in Chalcophile Elements (Sb,Sn, Te), and Ti-rich Varieties of Tripuhyute and Cassiterite from Sublimates of Active Fumaroles at the Tolbachik Volcano,Kamchatka, Russia

Geology of Ore Deposits - Abstract—The paper contains data on rutile, tripuhyite, and unusual Ti-rich cassiterite found in sublimates of active fumaroles at the Tolbachik volcano, Kamchatka,...     

Global Metallogenic Zonality of the Pacific Ore Belt

This article discusses problems of global metallogenic zonality of the Pacific Ore Belt (POB), which is understood as the complex of volcanogenic–plutonogenic units related to the evolution of the lithosphere of marginal seas; this lithosphere combines both continental and oceanic metallogenic features and also possesses a characteristic specificity of ore accumulation. It is shown that the ideas by S.S. Smirnov about the POB zonality have not considerably changed with time and, moreover, have been supported by the new global tectonic concepts. Nevertheless, the nature of metallogenic homogeneity of the external (Ag–Cu) and internal (Sn–W) zones of the POB seems to be more complicated and ambiguous. The metallogenic role of the Ag/Au ratio in ores of POB deposits is shown.     

Peculiarities of ore formation at the N’yavlenga Au-Ag epithermal deposit,Northeast Russia

Thermobarogeochemical studies have revealed the relatively high-temperature ore-bearing fluid of the N’yavlenga deposit. The dependence between the homogenization temperatures of the fluid inclusions and salinity of the fluid and the bimodal distribution of salinity values indicates mixing of two different fluids in the ore-bearing system. These facts are related to the thermal metamorphism of ores from the N’yavlenga deposit and indicate the complex relations of the early Au-Ag epithermal and late Au-Cu-Mo porphyry mineral complexes in orebodies of the deposit.