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61.
In the regional geodetic network of the Russian Far East, an active fault zone of the Kamchatka peninsula has been selected in order to study the relation between seismic activity and deformation. This paper provides the first results of a detailed and high-precision 3-km long levelling profile, along which geodetic data have been collected weekly for almost three years. The data processing and analytical methods that were originally used have been elaborated for this particular type of very small local network. In the active fault zone, two distinct ways of releasing accumulated potential energy, i.e. seismicity and 'fault superintensive movements', have been registered. The inverse correlation that is discovered between deformation rate and seismic activity could be useful in earthquake forecasts. 相似文献
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The paper deals with the results of geomorphological analysis of some photographs taken by the Mars 4 and 5 probes. The area studied (700 × 900 km, centered at 32°S, 35°W) covers part of Mare Erythraeum. The main landforms of the area are craters which are sorted into four morphological classes. Fluvial, eolian, and tectonic processes as well as downslope displacement of material are identified with different degrees of certainty.The valleys, which are probably of fluvial origin, exhibit a characteristic hierarchical pattern. The main valley in the area, provisionally named Uzboi, extends from Holden crater to Hale crater. The relations between the present surface elevations and the probable fluvial origin appear to indicate tectonic uplift of some parts of the area in the past. The tectonic movements have broken a hypothetical large valley into a number of fragments, one of which is Ladon valley and another of which is Uzboi valley, although another possible explanation of the observed pattern also exists. An attempt is made to divide the geologic history of the area into stages. The probable fluvial processes seem to have started before the end of the intensive impact cratetring stage. They appear to have continued, though not so intensely, almost to the recent stage. A geomorphological map of the area shownin Fig. 3. 相似文献
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Brigitte Stoll Klaus Peter Jochum Kirstin Herwig Marghaleray Amini Michael Flanz Berthold Kreuzburg Dmitry Kuzmin Matthias Willbold Jacinta Enzweiler 《Geostandards and Geoanalytical Research》2008,32(1):5-26
In this paper we describe a flux‐free fusion technique for the highly precise LA‐ICP‐MS bulk analysis of geological samples. For this purpose we have developed an automated iridium‐strip heater with temperature and melt time control. To optimise the homogeneity of the fused glasses and to reduce possible depletion of volatile elements during melting, we undertook experiments with basaltic rock and glass powders using different melting temperatures (1300–1700 °C) and melting times (5‐80 s). Major and trace element microanalysis was performed using EPMA and LA‐ICP‐MS. Homogeneous glasses were obtained for temperatures ≥ 1500 °C and melting times ≥ 10 s. High loss (20‐90%) of highly volatile elements (e.g., Cs, Ge, Sn, Pb) was observed for high melting temperatures (≥ 1600 °C) and long melting times (80 s). Standard melting conditions (1600 °C, 10 s) represent a compromise, as the glasses were homogeneous with respect to major and trace elements and, at the same time, were not depleted in elements with condensation temperatures (at a pressure of 10?4 bar) higher than about 900 K (e.g., Zr, Hf, Ba, Sr, REE, U, Mo, Ni, Rb, Ga). Several international geological reference materials with SiO2 ranging between 47% m/m and 59% m/m were prepared using our standard melting conditions (1600 °C, 10 s) and subsequently analysed by LA‐ICP‐MS. These samples also include the new Brazilian basaltic reference material BRP‐1. Matrix‐matched calibration of the LA‐ICP‐MS data was performed using the basaltic reference glasses KL2‐G, ML3B‐G, BCR‐2G and BHVO‐2G. Most analytical data agreed within uncertainty at the 95% confidence level with the GeoReM preferred values published in the GeoReM database for reference materials of geological and environmental interest. To demonstrate routine bulk LA‐ICP‐MS analyses of geochemical and cosmochemical samples using the whole rock fusion technique, we also present trace element data for ocean island basalts from Lanai (Hawaii) and of Martian meteorites. 相似文献
64.
A. A. Tomilenko T. A. Bul’bak M. O. Khomenko D. V. Kuzmin N. V. Sobolev 《Doklady Earth Sciences》2016,468(2):626-631
The composition of volatiles from fluid and melt inclusions in olivine phenocrysts from Yakutian kimberlite pipes of various ages (Olivinovaya, Malokuonapskaya, and Udachnaya-East) were studied for the first time by gas chromatography–mass spectrometry. It was shown that hydrocarbons and their derivatives, as well as nitrogen-, halogen-, and sulfur-bearing compounds, played a significant role in the mineral formation. The proportion of hydrocarbons and their derivatives in the composition of mantle fluids could reach 99%, including up to 4.9% of chlorineand fluorine-bearing compounds. 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - The results of long-term repeated levelling observations with increased spatial and temporal resolution (distance between benchmarks of 0.3–0.5 km... 相似文献
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Temperature is critical to maintaining seed viability under long-term storage conditions. It has been common practice to use refrigeration systems to maintain required storage temperatures. A seed repository constructed in permafrost in Yakutsk, Russia is the first seed storage facility that relies solely on natural cold. This paper describes the design and performance of the cooling system of the repository. An innovative aspect of the cooling system is that it utilizes the patterns of temperature wave propagation in permafrost. Predicted and measured ground temperatures for the first year of operation are presented and analyzed. Results indicate that convection air cooling systems can be used to control the temperature regime in underground facilities in permafrost. 相似文献