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1.
Lithology and Mineral Resources - Sedimentological features of the Upper Cambrian–Middle Ordovician rocks exposed in eastern Taimyr in the Faddey Gulf area are discussed. The studied sections...  相似文献   
2.
Theoretical and Applied Climatology - Rainfall components likely differ in the magnitude and direction of their long-term changes for any given location, and some rainfall components may carry a...  相似文献   
3.
Geomagnetism and Aeronomy - An empirical model of the equatorial anomaly in the critical frequency foF2 of the ionospheric F2 layer is constructed. The model is based on Interkosmos-19 satellite...  相似文献   
4.
Geomagnetism and Aeronomy - Diurnal variations in the statistical characteristics of the day-to-day variability in the electron number density NmF2 of the ionospheric F2 layer maximum is studied...  相似文献   
5.
Gorelits  O. V.  Kryjov  V. N.  Rakcheeva  E. A.  Ermakova  G. S. 《Water Resources》2022,49(5):836-844
Water Resources - Based on 1965–2020 series we have shown relationships between the features of the water runoff of the spring flood in mouths of large rivers of North-Eastern Europe and the...  相似文献   
6.
Marine ferromanganese nodules and crusts containing Mn, Cu, Ni and Co in the most promising resource-grade concentrations and quantities, together with Fe and Zn (all elements of biogeochemical importance) are found far from land on the deep seafloor of the Pacific Ocean. The biogeochemical, chemical and physical mechanisms contributing to their formation, distribution, abundance and – for these six elements – variability in their concentrations in these deposits, are the main focus of the present review. The mechanisms addressed include biological productivity, sedimentation types and rates, bottom water characteristics, the Calcium Carbonate Compensation Depth, the depth and intensity of the oxygen minimum zone, and biogeochemical characteristics of the six focal elements. Particular attention is given to comparisons between the deposits found in the north and the south Pacific, in order to present an overarching view of our current understanding of the mechanisms that apply to both nodules and crusts in both oceanic hemispheres, including examination of the possible existence of a marine ferromanganese oxide continuum. The renewed interest in the commercial exploitation of these deposits has stimulated a welcome increase in scientific research that is essential to informing the public discourse on seabed mining. We briefly reflect on the work addressed in this review in that context.  相似文献   
7.
Andreeva  I. V.  Puzanov  A. V. 《Water Resources》2022,49(1):154-162
Water Resources - English-language publications on the assessment of hazards and risks in recreation water use are reviewed. The main themes and results of foreign studies into the effect of...  相似文献   
8.
This study examined the application of slim-hole nuclear magnetic resonance (NMR) tools to estimate hydraulic conductivity (KNMR) in an unconsolidated aquifer that contains a range of grain sizes (silt to gravel) and high and variable magnetic susceptibilities (MS) (10−4 to 10−2 SI). A K calibration dataset was acquired at 1-m intervals in three fully screened wells, and compared to KNMR estimates using the Schlumberger-Doll research (SDR) equation with published empirical constants developed from previous studies in unconsolidated sediments. While KNMR using published constants was within an order of magnitude of K, the agreement, overprediction, or underprediction of KNMR varied with the MS distribution in each well. An examination of the effects of MS on NMR data and site-specific empirical constants indicated that the exponent on T2ML (n-value in the SDR equation, representing the diffusion regime) was found to have the greatest influence on KNMR estimation accuracy, while NMR porosity did not improve the prediction of K. KNMR was further improved by integrating an MS log into the NMR analyses. A first approach detrended T2ML for the effects of MS prior to calculating KNMR, and a second approach introduced an MS term into the SDR equation. Both were found to produce similar refinements of KNMR in intervals of elevated MS. This study found that low frequency NMR logging with short echo times shows promise for sites with moderate to elevated MS levels, and recommends a workflow that examines parameter relationships and integrates MS logs into the estimation of KNMR.  相似文献   
9.
Lithology and Mineral Resources - The results of studying the material composition of sandy rocks in Cretaceous deposits of the West Sakhalin Terrane are considered. Studies were carried out to...  相似文献   
10.
Water Resources - Publications on changes in river water regime in Russia under the conditions of current climate changes are reviewed. Most recent generalizations of such publications are...  相似文献   
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