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991.
992.
The Riphean rocks of the Baikit anteclise have been examined using pyrolysis Rock–Eval 6 to evaluate the subsidence history and erosion level. The studied Riphean rocks have the МK3–МK4 catagenesis grade. Based on the catagenesis of organic matter we propose a model of maximum burial before the beginning of the accumulation of Vendian deposits. Estimated calculations of subsidence and erosion have shown that the assessed catagenesis grade could be reached at a depth of 7 km, while the erosion level was approximately 5–7 km.  相似文献   
993.
This work describes a young extrusive massif in the uppermost reaches of the Chegem River (Bashilauzu-su River), which had been considered as a feeder of the great sequence of Upper Pliocene rhyolite ignimbrites of the Verkhnechegemskaya caldera. The Upper Pleistocene age of the stratum, extrusive origin of automagmatic breccias and fluidolites, as well as its difference from rhyolites of the caldera are proven. The Bashilsky swell, located in the Late Pleistocene glacial trough, is evidence of young volcanism in this area, which has not been previously proposed.  相似文献   
994.
The problem of studying the Domanik deposits and their reservoir potential is among the most important ones. The discovery of hydrocarbon deposits in similar rocks at various depths, the considerable variability of reservoir properties, and ambiguity in establishing the values of the effective thickness set the task for researchers to estimate them more reliably. The high-carbon kerogenic-carbonate-siliceous stratum that is characterized by the development of differently-oriented systems of fractures is of outstanding interest.  相似文献   
995.
Based on the spore-pollen data, the mineral composition of clay rocks, analyzed structures and facies, and a general paleogeographic analysis, the sedimentation conditions and landscapes of islands located during the Late Bajocian in the region of the present-day the Crimean Mountains have been reconstructed. It is shown that the sublatitudinally elongated insular land zone had a width of 30 km, the heights of the islands were no more than 1 km, with steep mudflow-affected northern slopes and with an extensive river system on the southern slopes.  相似文献   
996.
An essentially new method for the allocation of diamondiferous kimberlite pipes against surrounding rocks is proposed. The method is based on the interpretation of multispectral LANDSAT-7 ETM+ satellite images; it allows one to find the most promising areas within perspective sites revealed by other methods. It is demonstrated that application of GIS technologies for comprehensive use of geological, geophysical, and mineralogical data and the results of the interpretation of satellite images is efficient for predicting kimberlite diamond deposits in both studied areas and poorly explored territories.  相似文献   
997.
Engineering-geological (geotechnical) structures are distinguished based on a combination of regional and zonal geological factors. Classifications of engineering-geological structures of the Earth and Russia are presented. The main engineering-geological characteristics and spatial distribution patterns of continental subaerial, continental subaquatic, and transitional predominantly subaquatic and oceanic predominantly subaquatic engineering- geological mega- and macrostructures distinguished in Russia are described.  相似文献   
998.
Space weather prediction involves advance forecasting of the magnitude and onset time of major geomagnetic storms on Earth. In this paper, we discuss the development of an artificial neural network-based model to study the precursor leading to intense and moderate geomagnetic storms, following halo coronal mass ejection (CME) and related interplanetary (IP) events. IP inputs were considered within a 5-day time window after the commencement of storm. The artificial neural network (ANN) model training, testing and validation datasets were constructed based on 110 halo CMEs (both full and partial halo and their properties) observed during the ascending phase of the 24th solar cycle between 2009 and 2014. The geomagnetic storm occurrence rate from halo CMEs is estimated at a probability of 79%, by this model.  相似文献   
999.
1000.
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