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1.
The analysis of paleomagnetic data available for the southern Primiorye region revealed that the studied objects were magnetized under regional remagnetization presumably during the Late Mesozoic folding and this magnetization can be interpreted as being synfolding. The interpretation is based on the parameter that characterizes the folding completion degree immediately before regional remagnetization. It is shown that the relaxation of Late Mesozoic horizontal stresses was irregular. The obtained estimates of the degree of folding completion are consistent with the available geological data and Talitskii’s model for tectonic deformations.  相似文献   
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Geochronological database considered in the work and characterizing the Anabar collision system in the Northeast Siberian craton includes coordinated results of Sm-Nd and Rb-Sr dating of samples from crustal xenoliths in kimberlites, deep drill holes, and bedrock outcrops. As is inferred, collision developed in three stages dated at 2200–2100, 1940–1760, and 1710–1630 Ma. The age of 2000–1960 Ma is established for substratum of mafic rocks, which probably originated during the lower crust interaction with asthenosphere due to the local collapse of the collision prism. Comparison of Sm-Nd and Rb-Sr isochron dates shows that the system cooling from ≈700 to ≈300°C lasted approximately 300 m.y. with a substantial lag relative to collision metamorphism and granite formation. It is assumed that accretion of the Siberian craton resulted in formation of a giant collision mountainous structure of the Himalayan type that was eroded by 1.65 Ga ago, when accumulation of gently dipping Meso-to Neoproterozoic (Riphean) platform cover commenced.  相似文献   
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Complex experimental research of thermal properties of oil-contaminated frozen soils was carried out. On the basis of the obtained results the influence of the various factors connected with oil pollution on heat transfer in frozen soils was analyzed. And the model of heat transfer in frozen soils was offered.  相似文献   
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Structure of the basins of the White Sea rift systems   总被引:1,自引:0,他引:1  
For the first time, the structure of the sedimentary basins of the Late Proterozoic rift system in the White Sea is characterized based on a set of new marine geological geophysical data such as the results of the common depth point seismic method, gravity and magnetic data, and seismoacoustics. The main tectonic structures in the topography of the heterogeneous basement within the basin of the White Sea are distinguished and described. A structural tectonic scheme of the basement surface is presented. The thicknesses of the sediments are estimated and the stratigraphic confinement of the seismic units recognized is done.  相似文献   
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Weathering crusts of the sedimentary basin basement are collectors in several regions of the world. They enclose huge reserves of oil and gas. The paper considers the geochemical, mineral, and petrophysical heterogeneities of weathering crusts that should be taken into consideration in the prospecting, exploration, and development of hydrocarbon raw material therein. Areal and linear-fissure types of weathering crust are defined. They were formed before the overlapping of basement by rocks of the sedimentary cover. Areal crusts are pervasive at the basement roof, whereas linear-fissure crusts are formed along fractures. A complete weathering crust profile includes the following zones (from the bottom to top): disintegration, leaching and hydration, hydrolysis, and final hydrolysis. Rocks of the lower two zones represent the cavernous-fissure collector, while rocks of the upper zones are impermeable. In the arches of uplifted blocks of the basement, weathering crusts are subjected to erosion during marine transgressions. In such places, the roof is composed of rocks of the lower permeable zones that often make up a single heterogeneous natural reservoir overlapped by sandy collectors of sedimentary sequences. Linear-fissure weathering crusts show zonal distribution with good filtration-capacity properties. Several large oil and gas pools have been discovered in them.  相似文献   
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A daily periodicity in small (K ≤ 8. 0) Kamchatka earthquakes has been detected, with the maximum occurring during the nighttime. The effect was not observed throughout the area of study, but only in several zones. We show that the results are not affected by human and weather factors. A hypothesis is put forward to explain the physical causes of the effect, viz., that the daily periodicity of small earthquakes could be due to natural VLF electromagnetic radiation acting on the geologic medium. It is pointed out that the effect is related to the previously identified effect of natural electromagnetic radiation modulating the intensity of geoacoustic emission from rocks.  相似文献   
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An experimental study of the particulars of the solubility and crystallization of brushite Ca(HPO4) · 2H2O from aqueous solution in conditions of a variable pH (6.0–3.0) and the contents of impurity ions (K+, Na+, NH 4 + , Mg2+, SO 4 2? , CO 3 2? ) has been conducted. It is established that brushite solubility markedly rises with a decrease in pH from 6 to 3 and slightly rises with an increase in Mg2+ and SO 4 2? concentrations. The enrichment in K+, Na+, and NH 4 + does not affect brushite solubility. The changeable chemistry of the medium results in variation of the synthetic crystal habit, from rhombic tabular to thickened prismatic crystals.  相似文献   
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