<Emphasis Type="Italic">Q</Emphasis>-type bursts in magnetic oscillations of ELF range as a phenomenon reflecting the properties of the global Earth-ionosphere resonator

The observation results of Q-type bursts in the measurements of the horizontal component of the noise magnetic field in the range of the first Schumann resonance in polar regions (Lovozero high-latitude observatory) are presented. Automatic selection of Q-type bursts from the experimental data series is implemented on the basis of a waveform recognition algorithm. The resonant nature of Q-bursts is shown. The possibility of selecting such events in magnetic excitation conditions is highlighted. The global resonator quality upon decreasing the selected waveform amplitudes is estimated. The data obtained by this method are compared with estimates on the basis of Fourier analysis and values known from the world literature. The possible reasons for disagreements of the estimates are analyzed, including the problem of selecting the function approximating the spectrum, the problem of accounting for the background, and the possible irregularity of the spectrum. It is shown that Q-type bursts, besides the quality, allow estimating the resonant frequency of the first oscillation mode; however, the accuracy of such estimation is lower as compared to the results of Fourier analysis methods.     

The new data on the origin of the Patom Crater (East Siberia)

It has been found that the origin of the Patom Crater is related to endogenous processes with the main role played by deep flow of fluid components, which determine formation of the ejecta cone at about 500 years ago or more. This is evidenced by the zonal structure of the crater and geochemical peculiarities of rocks, caused by the long formation time for particular zones. Sandstone and schist blocks that were included into eruptive breccia within the crater were affected by gaseous or fluid components and intensively carbonized. During carbonatization, these rocks within the crater were being enriched in Ca and Sr, but the shares of the ⁸⁷Sr and, consequently, ⁸⁷Sr/⁸⁶Sr ratio in them abruptly decrease. This is explained by the influence of deep fluids on terrigenous rocks, which were initially depleted in the radiogenic strontium isotope and might flow from a magmatic source with a low ⁸⁷Sr/⁸⁶Sr ratio. However, these fluids were enriched in CO2 and transported significant quantities of Sr, which led to enrichment of all terrigenous rocks in the crater in this element. The discovery of individual sandstone blocks with high concentrations of summarized rare earth elements (up to 557 g/t) and higher Sr and Ba contents among the fragments of host stratum within the Patom Crater allows us to suppose that there is a magmatic source enriched in fluid components at depths. The effect of the active fluid phase with low strontium isotopic ratios on rocks during the Patom Crater formation might lead to an abrupt decrease in values of the initial ⁸⁷Sr/⁸⁶Sr ratio in carbonized sandstones and schists.     

Seismic and infrasonic monitoring on the Spitsbergen archipelago

In late 2010, the Geophysical Survey, Kola Branch, Russian Academy of Sciences installed a system of constant seismic and infrasonic monitoring on the Spitsbergen archipelago. To date, this system is the only tool to implement joint monitoring of seismic and infrasonic events in this part of the Arctic. The hardware and software structure of subsystems of monitoring and data transmission are considered. The automatic detection of infrasonic events is described. Widespread commercially available hardware components have been used. Preliminary results of the seismic and infrasonic monitoring on the Spitsbergen archipelago in 2011 are given. A hypothesis is developed about the relationship between infrasonic and seismic emissions with the processes occurring in the cryosphere of the archipelago.     

Magmatism evolution and carbonatite-granite association in the neoproterozoic active continental margin of the Siberian craton: Thermochronological reconstructions

Neoproterozoic carbonatites and related igneous rocks, including A-type granites in the Tatarka-Ishimba suture zone of the Yenisey Ridge are confined to a horst-anticlinal structure that was formed in a transpression setting during the oblique collision between the Central Angara terrane and the Siberian craton. The carbonatites, associating mafic (including alkaline) dikes as well as the Srednetatarka nepheline syenites are the oldest igneous formations of the Tatarka active continental margin complex. Geochronological data indicate that magmatic evolution continued in the studied anticline for nearly 100 m.y. On the earliest stage carbonatites were formed and on the last stage — the emplacement of mantle-crustal A-type Tatarka granites took place. According to new U/Pb zircon studies, the earliest rocks in the Tatarka pluton are A-type leucogranites aged 646 ± 8 Ma. The younger ⁴⁰Ar/³⁹Ar ages of carbonatites obtained for phlogopites (647 ± 7 and 629 ± 6 Ma) are related to the last tectonic events in the studied region of the Tatarka-Ishimba suture zone, which are coeval with the formation of the A-type granitoids (646–629 Ma).     

The role of cosmic and ionospheric disturbances in global climatic changes and pipeline corrosion

Physical causes controlling the influence of the main cosmic factors on the state of the ionosphere and, further, on weather and climatic phenomena, including the global warming, are investigated. These investigations are based on the Rydberg excitation of the experimentally observed microwave radiation of the Earth’s ionosphere by energetic ionospheric electrons. This microwave radiation virtually freely penetrates into the lower atmosphere, providing channels for the influence of solar variability on terrestrial phenomena. The factors causing an anomalous wear of Russian pipeline systems are also analyzed, and the methods for reducing their rapid corrosion through taking into account the influence of heliogeomagnetic and ionospheric disturbances are described. Such investigations are supported by the space experiment on permanent monitoring of the factors controlling heliogeomagnetic activity, i.e., fluxes of ionizing radiation of the Sun and fluxes of electrons precipitating from the radiation belts.