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821.
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   
822.
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   
823.
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   
824.
The Abor volcanics of the continental flood basalt affinity are extensively exposed in different parts of the Siang valley. These are associated with Yinkiong Group of rocks of Paleocene–Eocene age and represent syn-sedimentary volcanism in a rift setting. Subsequent folding and thrusting of the Siyom and Rikor sequences above the Yinkiong Group of rocks represent changes from syn-to-post collisional brittle-ductile tectonic episodes. Mylonitic Abor volcanics in the thrust contacts are studied at several locations in the north and south of Puging in the Siang valley. Both the Abor volcanics and associated Rikor and Yinkiong Group of rocks preserve meso to micro-scale fabric asymmetries indicating that the thrust contacts are shear zones of brittle-ductile nature containing mylonitic textures of high shear strain. Two distinct hitherto unrecognised shear zones in the north and south of Puging are named as North Puging Shear Zone (NPSZ) and South Puging Shear Zone (SPSZ). The kinematic indicators along the thrust contact indicate oblique slip thrusting of the Rikor and Siyom thrust sheets above the Yinkiong Group of rocks. This paper provides field evidence proving that the compression due the Burmese plate made oblique slip thrusting and zones of mylonitised volcanics possible and associated metasediments were formed. The kinematic indicators in the NPSZ and SPSZ respectively indicate top-to-SSE and top-to-NNW sense of shears.  相似文献   
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