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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.
Prajapati  V. K.  Khanna  M.  Singh  M.  Kaur  R.  Sahoo  R. N.  Singh  D. K. 《Theoretical and Applied Climatology》2022,149(1-2):207-220
Theoretical and Applied Climatology - This paper presents a composite approach for drought characterization and monitoring using in situ and remote sensing-based drought indicators. The study was...  相似文献   
3.
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   
4.
Geomagnetism and Aeronomy - Based on an analysis of data from the midlatitude ionospheric stations, it is found that the P = 0.5(F1 + F81) index is an optimal solar-activity index for the daily...  相似文献   
5.
Theoretical and Applied Climatology - Empirical frequency distribution of daily precipitation amounts can be fitted by a negative exponential distribution, because anywhere there are many small...  相似文献   
6.
Atabekov  I. U.  Sadykov  Yu. M. 《Geotectonics》2022,56(3):306-320
Geotectonics - Seismic and tectonic processes were analyzed, taking into account the dimensions of tectonic structures and geological factors that determine the features of the relationship between...  相似文献   
7.
Geomagnetism and Aeronomy - Analysis of the features of the form of low solar cycles 23 and 24 for the solar-activity indices (F is the solar radio flux at a wavelength of 10.7 cm, Rz and Ri are...  相似文献   
8.
We use particle tracking to determine contributing areas (CAs) to wells for transient flow models that simulate cyclic domestic pumping and extreme recharge events in a small synthetic watershed underlain by dipping sedimentary rocks. The CAs consist of strike-oriented bands at locations where the water table intersects high-hydraulic conductivity beds, and from which groundwater flows to the pumping well. Factors that affect the size and location of the CAs include topographic flow directions, rock dip direction, cross-bed fracture density, and position of the well relative to streams. For an effective fracture porosity (ne) of 10−4, the fastest advective travel times from CAs to wells are only a few hours. These results indicate that wells in this type of geologic setting can be highly vulnerable to contaminants or pathogens flushed into the subsurface during extreme recharge events. Increasing ne to 10−3 results in modestly smaller CAs and delayed well vulnerability due to slower travel times. CAs determined for steady-state models of the same setting, but with long-term average recharge and pumping rates, are smaller than CAs in the models with extreme recharge. Also, the earliest-arriving particles arrive at the wells later in the steady-state models than in the extreme-recharge models. The results highlight the importance of characterizing geologic structure, simulating plausible effective porosities, and simulating pumping and recharge transience when determining CAs in fractured rock aquifers to assess well vulnerability under extreme precipitation events.  相似文献   
9.
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   
10.
Mikhailova  M. V. 《Water Resources》2022,49(5):753-765
Water Resources - The current state, the hydrological problems of river mouths, and the history of their studies as specific geographic objects are discussed, and the main lines and schools of...  相似文献   
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