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[en] Complete text of publication follows. High-density array MT soundings of the crust in the seismically active northern Tien Shan were performed using Phoenix MTU-5 stations in the Bishkek Geodynamic Polygon, at the junction of the Chu basin and the Kyrgyz Range. The MT transfer functions were determined to an accuracy of 1-2% (amplitude) and about 0.5-0.8 deg (phase) in most of 145 soundings. Preliminary analysis of the collected data aimed at estimating the geoelectrical dimensionality. The Bahr decomposition analysis indicated the presence of local 3D structures in the crust of the area superposed on the regional 2D structure. As a result of 2D inversion of amplitude and phase data with Randy Mackie codes, the geoelectric cross-sections along MT profiles have been constructed. Inversion models image upper-mid crustal zone of enhanced conductivity of the Issyk-Ata fault. Resistivity of this conductive zone is not exceeding 100 ohm-m. The conductor is connected to the surface structure and its upper part coincides with the line of Issyk-Ata fault on the surface. The low resistivity zone in the southern part of the investigated area is gently plunged into the southern direction beneath the rise of the Kyrgyz Range. Apparently, this zone represents large crust's zone of tectonic decollement and weakening with high fluid-gas environment permeability with properties of the waveguide. Next actual implication reveals from comparison of local seismicity spatial distribution and resistivity structure. One can clearly see the high seismicity clustering around the edge of conductive zones, thus we suggest that the local seismicity results either from the migration of the fluids to less permeable crust or from local stress concentration near the structural boundaries. So, presented results of high resolution magnetotelluric survey show that geoelectric imaging of fault zones deliver us the unique information of deep structure features and sometimes it can give us new unexpected tectonic explanations for studied objects. In addition to these structural EM investigations in 2003 Research Station RAS (Bishkek, Kyrgyzstan) and Phoenix Geophysics (Toronto, Canada) jointly installed two permanent stations at the seismogenic zone near Bishkek for monitoring natural and artificial electromagnetic fields, using Phoenix magnetotelluric equipment MTU-5D. MT parameters computed daily for the whole period of these observations are presented. Wavelet analysis was executed for the time series of daily average values of apparent resistivity (modules and phases) for two stationary stations of ?? measurements since autumn of 2003. The time intervals till a few months duration with abnormal behaviour of apparent resistivity variations in the period sounding range T=5-100s are marked, but for all that the maximum of change makes only the first percents. Such long-term change of resistivity has correlation with seismic activity in the region and, probably, can reflect the activation period of the structures in the mid-low crust at the Northern Tien Shan. The work was supported by RBRF grant 07-05-00594a.
[en] Complete text of publication follows. The ancient Tien Shan intra-continental range reactivated in the late Cenozoic due to India-Eurasia collision continues to grow rapidly up to the present. The magnetotelluric investigations of the Central (Kyrgyz) Tien Shan, the focus of modern geodynamic activity, are carried out by the Research Station RAS (Bishkek) during last twenty years with the main goal to formulate and constrain different hypotheses of its evolution. The researchers of NARYN WG have developed effective approaches to analyze and interpret the Tien Shan array of EM soundings. In this presentation we show the multi-component inversion results for magnetotelluric (MT) and magnetovariational (MV) data along three sub-longitudinal profiles across the Central Tien Shan. The comprehensive interpretation of the broad-band and long-period data of the most representative NARYN transect (going from the Kazakh plate to the Tarim Basin along 76 degE) are supported by the results of imitation studies as well as by the latest seismological data. The anomalous structures of geoelectric cross-section along 76 degE line are correlated with the features revealed in the course of broad-band sounding data inversions at two shorter regional profiles (74 degE and 78.5 degE). On the way to the spatial synthesis of multi-profile conductivity sections into a Tien Shan volume geoelectric model we analyzed the behavior of main MT/MV transfer functions over the area. The presented spatial-period distributions of these responses are characterized by bright anomalies, which correlate with other geophysical data and outline principle geotectonic structures of the Central Tien Shan. Acknowledgements to RFBR grants 08-05-00875 and 07-05-00594.
[en] Soviet industry of mercury and stibium was located in South-East Fergana in Kyrgyzstan and Uzbekistan boarder. Khaidarken combine produced high pure mercury (99.9997 percent) since 1940, it was the second source in the World (after Almadena, Spain). Maximal production was 790 t in 1990, after Transitional Shock about 300 tons a year. Tail was established in 1967. There is special tube 5500 m transporting pulp to tail. The pulp contains about 0,003 mg/liter mercury, 0,005 mg/liter arsenic, 21 mg/liter stibium, etc. Pulp is cleaned by aluminum sulfuric and mortar. After drying and compressing by itself the concentrations rises: mercury 90-250 mg/kg, arsenic 190-400, stibium 800-1700 mg/kg. Environment pollution problem contains three kinds: ground water infiltration; old tube corroding some places (leaking from chink of tube) - both mentioned lead to vegetables cumulating; combine work spreading mercury by air to settlement Khaidarken. Kadamjay enterprise for stibium (mines, combine, purify plant, tails) began work in 1936. Most part of production used in soviet military. Maximal production was 17.000 t clearing ore in 1990, after USSR collapse 1-6 t/year. Tremendous tails and dams (total 150 mln t) remains non re-cultivated until now. The tails contain electrolysis wastage: sodium-sulfides, sulfites, sulfates; stibium; arsenic; cadmium; stibium; etc. Seven deposits (tail-damp really) established 1976, total square 76.1 thousands sq m, total volume 250 thousand cub m. The deposits over-filled, contents filtrating - little saline or lakes generated (one situated 50m near Uzbekistan boarder). River Shakhimardan flow to Uzbekistan (settlement Vuadil, Ferghana town). There are health damage indices in the areas.(author)
[en] The Lake Issyk-Kul' of the central Tyan-Shan is characterized by increased natural uranium content. Uranium-carbon deposit situated on the southern bank of the Lake can be the reason of chemical and radioactive contamination of this unique basin by exploitation wastes. In order to estimate possible danger, a project 'Assessment and prognosis of environmental changes in Lake Issyk-Kul' (Kyrgyzstan)' was developed and supported by the Program of the European Commission 'Copernicus-2' (2001-2003). According to this project the water assays were sampled from different depths near the banks of the Lake and from low-debit sources draining the dumping grounds of the uranium-carbon deposit. Elemental and isotopic examinations of these water samples were performed using an ELEMENT HR-ICP-MS (Finnigan Mat). The results obtained are the evidence that the ecological status of the Lake Issyk-Kul'is not damaged at present. Wastewaters from the uranium-carbon mine do not make decisive contribution into the natural radioactive background. (authors)
[en] Complete text of publication follows. Statistical verification of hypothesis of earthquake triggering by interaction of geomagnetic field and telluric currents proposed by G. Duma and Yu. Ruzhin  is presented. The analysis has been performed for the Northern Tien Shan region (40.5 deg-44.5 degN, 71.5 deg-78.5 degE) where the Research Station of Russian Academy of Sciences is located near Bishkek city (Kirghizia). Based on the long-term observations of various geophysical fields the analysis employs detail geoelectrical model of the Earth crust, catalog of mechanisms of earthquake sources, as well as known faults and stress field derived from GPS observations. Possible correlation of seismic activity of the Northern Tien Shan region (40.5 deg-44.5 degN, 71.5 deg-78.5 degE) and variations of geomagnetic magnetic field, as well as the lunar-solar earth tides within the period 1994-2007 is analyzed. By application of various statistical methods (cross-correlation, spectral analysis) it was shown that the earthquake daily frequency distribution has common behavior with the regular diurnal geomagnetic field variations. The effect is strongly depends on the earthquake source mechanism (fault orientation). The work is supported by Russian Foundation for Basic Research (RFBR grant No. 09-05-00919-a 'Analysis of Complex Mechanical and Electromagnetic Triggering Impact on the Earthquake Source')
[en] In connection with that this seismic in the territory of Naryn cascade maybe has its peculiarity in cludding in the territory Toktogul reservoir before of the building of the Toktogul dam, during of the building and after accordingly was decided to consider the seismic in this space of times. The arm of the present paper is estimation seismic of the territory Toktogul reservoir for different times: before of the building of the Toktogul dam (1960-1973), during its filling (1974-1980) and since start it's of the uninterruptedly exploitation to present time (1981-2006). The territory in that located the cascade of Naryn River is considered that seismic active in the Central part of the Tien Shan. The tectonic motions are become here intensity. The presence of the large faults is complicating significantly the seismic situation of the study region
[en] The topic of radioactive contamination investigation is of present interest. In Soviet time, a dynamic uranium mining was taking place in some regions of the Republic, including the Issik-kul region. According to medical and statistical information (1988-1998), these regions are featured with a high rate of oncologic diseases.The International Scientific Center of American Fund Grant conducted radioecological investigations in Issik-kul region, including radiation survey of the terrain and analysis of soil and water samples by the thorium and radium content.The investigations were conducted using American methods and a set of the up-to-date equipment that allows both a precise measuring Y-background parameters and recording exact position of a site, date and time as well.The measuring methods imply a simultaneous positioning, using device E600 OPT19 Instrument Carrying Strap, and measuring gamma-background level, using detector Eberline E-600/SPA-8. All information about a position, radiation background values, date, measuring time is then transferred to computer using the memory package.The investigation outcomes are given as a sheet of dose loads of natural gamma-radiation in different areas of the region. The obtained outcomes are of a great interest
[en] Complete text of publication follows. The ancient Tien Shan intra-continental range reactivated in the late Cenozoic due to India-Eurasia collision continues to grow rapidly up to the present. The magnetotelluric investigations of the Central (Kyrgyz) Tien Shan, the focus of modern geodynamic activity, are carried out by the Research Station RAS (Bishkek) during last twenty years with the main goal to formulate and constrain different hypotheses of its evolution. The researchers of NARYN WG have developed effective approaches to analyze and interpret the Tien Shan array of EM soundings. In this presentation we show the multi-component inversion results for magnetotelluric (MT) and magnetovariational (MV) data along three sub-longitudinal profiles across the Central Tien Shan. The comprehensive interpretation of the broad-band and long-period data of the most representative NARYN transect (going from the Kazakh plate to the Tarim Basin along 76 deg E) are supported by the results of imitation studies as well as by the latest seismological data. The anomalous structures of geoelectric cross-section along 76 deg E line are correlated with the features revealed in the course of broad-band sounding data inversions at two shorter regional profiles (74 deg E and 78.5 deg E). On the way to the spatial synthesis of multi-profile conductivity sections into a Tien Shan volume geoelectric model we analyzed the behavior of main MT/MV transfer functions over the area. The presented spatial-period distributions of these responses are characterized by bright anomalies, which correlate with other geophysical data and outline principle geotectonic structures of the Central Tien Shan. Acknowledgements to RFBR grants 08-05-00875 and 07-05-00594.
[en] Full text: As the Second World War came to an end and the Cold War just started, the Soviet Union was faced with a problematic necessity of the nuclear weapons' production. Indeed, the Soviet Empire was in the extreme need of such weapons since their possession was viewed as an only guarantee of peaceful relations between USSR and United States. Exactly in that period the Soviet Union started its intensive exploitation of the large radioactive ore deposits (basically, uranium and radium), located on the territory of the present-day Kyrgyzstan. Throughout the post-war cold period and right up to mid-80s Kyrgyzstan had been one of the leading producers of uranium in the Soviet Union. In fact, the first Soviet atomic bomb was produced using Kyrgyz uranium. In the intense arms race with United States there was no time to concern oneself with environmental and demographic protection of the exploited territory, unfortunately. The role of the Kyrgyz ASSR (Kyrgyz Autonomous Soviet Socialist Republic) was to provide raw materials, concurrently being a conveniently remote place to treat foreign radioactive ores (imported from Eastern Germany and Czechoslovakia) and serving as a burial place for their wastes. Creating an enormous amount of the radioactive wastes, the uranium and radium ore deposits were located in immediate proximity to highly populated areas; in the basins of transboundary rivers; and in the seismic-active regions of the Republic. As it could be legitimately assumed, the Soviet Union was not deeply obsessed with the environmental peculiarities of the treated area and did not give a damn to its protection, being solely interested in the maximization of the uranium extraction. In 1991, immediately after the Soviet Union's dissolution, the Russian Federation officially proclaimed itself its successor. Consequently, it was Russia that received the bigger part of a huge military potential (particularly, nuclear one) of its predecessor, including the nuclear weapons' arsenal. Yet, the newly independent Kyrgyz Republic was left alone with an enormous amount of uranium waste, which was extracted on the Kyrgyz territory to produce these nuclear armaments. As a consequence of the Soviet policy, uranium waste storage sites represent a direct danger to the environment of present-day Kyrgyzstan. Therefore, Russia as the official successor of the Soviet Empire should help the Kyrgyz Republic to deal with this costly and extensive problem. These environmental issues serve as a basis for the given work. In turn, research will be primarily concentrated on several the most problematic radioactive waste storage sites, namely, the Mailuu-Suu, Kadji-Say, Kara-Balta, and Ak-Tuz uranium storages. Today, Kyrgyzstan has 50 radioactive waste storage sites, located throughout its territory and contained altogether about 300 million tons of wastes. In general, it could be suggested that the financial responsibility could be delegated to the Kyrgyz government; the Central Asian Community; Russia. It is clear with the first instance, the Kyrgyz government, as it ought to deal with the environmental problems of its country. The situation is more sophisticated and arguable in terms of second and third instance, namely, the Central Asian Community and, particularly, Russia. This paper is designed to prove not only the necessity for their involvement, but rather their responsibility for the present-day situation with the Kyrgyz storage sites. As regards the other Central Asian States, it is in their interests since they are under immediate threat of being affected. Concerning Russia, it is rather a moral right to demand its assistance than a legally legitimate one. All information, related to uranium, its extraction and further utilization was totally classified and only revealed after the Soviet Union's dissolution. Only in 1994 did the Kyrgyz public become acquainted with the truly poor environmental conditions of the newly fledged Republic. Yet, no radically efficient measures had been undertaken during the following 6 years of Kyrgyz independence. Consequently, it has become apparent that Kyrgyzstan is not able to solve its problems because of the lack of resources. Even the preliminary monitoring of the radiation conditions in the most endangered areas indicates a cost approximately US $ 3-5 million. For instance, the sanitation of the Mailuu-Suu complex is valued at about US $ 0.5-0.7 million per storage site, while there are 23 of them. The given research has presented a broad analysis of the current ecological situation in Kyrgyzstan, having revealed and described its most problematic and challenging cases. In addition, it has included a series of short interviews that have been conducted by the author in order to elucidate people's awareness about and attitude toward the present-day grave conditions of the Kyrgyz environment - especially, in the case of radioactive wastes. Predominantly, the author's main objective was to prove the necessity for CIS's involvement and cooperation in dealing with Kyrgyz waste storages since Kyrgyz uranium served for the defense of the whole Soviet Empire