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L. F. Kopaevich A. S. Alekseev A. M. Nikishin V. N. Ben’yamovskii E. V. Yakovishina E. A. Sokolova A. I. Voznesenskii 《Moscow University Geology Bulletin》2007,62(3):164-172
This paper presents data on the structure of reference sections of the Maastrichtian-Danian boundary beds and the assemblages of benthic and planktonic foraminifers enclosed in these rocks. These are based on examination of the reference sections in two different structure-facies zones of the Mountainous Crimea: the Kacha Uplift and Indol-Kuban Trough. The strongly different lithologic and foraminifer assemblages in these sections indicate the presence of completely different water masses in the shelf part of the marine basin with water depths varying from those of the middle-lower sublittoral zone (in the Belbek, Beshkosh, and Chakhmakhly sections in the southwestern part of the Mountainous Crimea) to those of the pelagic environment on the continental slope and at the continental rise (section in Mount Klement’ev in the Indol-Kuban Trough). These assemblages indicate the sedimentation environment in the transition zone between the Kacha shelf and the deep-water Black Sea Basin. 相似文献
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An analysis is made of the geobotanical forecasting technique. Mapping is known to be recognized as the most powerful method of forecasting-geobotanical investigations. A close interrelation between geobotanical forecasting and vegetation mapping is demonstrated. To improve objectivity of the findings used cartographic models of modern and predicted vegetation which most fully represent the entire structuralcenotic diversity of plant communities in Prebaikalia, the central region of Baikalian Siberia. The predictive constructions are based on analyzing modern vegetation which always includes structural features of its future that manifest themselves in primary and stable derivative communities. We developed the legend and compiled the map (sc 1:200 000) of the region’s modern vegetation. The state of the natural environment of the Lena- Angara interfluve is assessed having regard to the various functions of plant communities in geosystems. The 1:200 000 map of probability-forecasted (within 200 years) vegetation is presented for Lena-Angara interfluve. It is shown that complete recovery of the primary structure will not occur within 200 years. It is found that it is necessary to carry out predictive-cartographic investigations for the whole of Baikalian Siberia as vegetation of this region is characterized by a decreased activity of recovery processes occurring under the influence of anthropogenic factors. The reason has to do with the harsh natural conditions where it is not worthwhile to pursue extensive nature management, such as is universally the case to date, leading to undesirable economic consequences, because the degree of disturbance to vegetation in a number of areas of Prebaikalia has now reached as critical level. It is concluded that a further policy of nature management on this territory must be built upon the new principles to be approved by government documents. 相似文献
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O. V. Sokolova D. V. Grichuk T. V. Shestakova K. A. Pestova 《Moscow University Geology Bulletin》2008,63(2):95-107
The distribution of heavy metals has been examined in water and bottom sediments of small streams within the Losinyi Ostrov (Elk Island) National Park (Moscow) that are undergoing manmade impacts. We demonstrated that pollution caused by motor vehicles causes seasonal changes in the general composition of the river water and pore solutions in bottom sediments. The strongest pollution of water and sediments was found near the CMHW (Circum-Moscow Highway) (Zn, Pb, Cu). This is expressed in the growth of mobile forms of metals in sediments. We have shown, using Zn as an example, the pollution transformation in the snow-river water-suspension-bottom sediment system. 相似文献
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Eleven new estimates of heat flow (q) from the southern Altai-Sayan Folded Area (ASFA) have provided update to the heat flow map of Gorny Altai. Measured heat flow in the area varies from 33 to 90 mW/m2, with abnormal values of >70 mW/mq at four sites. The anomalies may have a deep source only at the Aryskan site in the East Sayan (q = 77 mW/m2) while high heat flows of 75–90 mW/m2 obtained for the Mesozoic Belokurikha and Kalguty plutons appear rather to result from high radiogenic heat production in granite, which adds a 25–30 W/m2 radiogenic component to a deep component of 50–60 mW/m2. The latter value is consistent with heat flow estimates derived from helium isotope ratios (54 mW/m2 in both plutons). Heat flow variations at other sites are in the range from 33 to 60 mW/m2. The new data support the earlier inferences of a generally low heat flow over most of ASFA (average of 45–50 mW/m2) and of a “cold” Cenozoic orogeny in the area (except for southeastern ASFA), possibly driven by shear stresses associated with India indentation into Eurasia. 相似文献
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Rogozhin E. A. Sokolova E. Yu. Somala S. N. Andreeva N. V. Raghucharan M. C. 《Geotectonics》2020,54(1):75-82
Geotectonics - The geological and geophysical study of the representative segment of the Alpine-Himalayan mobile belt—the Central zone of the Garhwal Himalaya—was conducted. The results... 相似文献
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Presented are the results from the assessment stage of forecasting-cartographic investigations into the vegetation in the Angara-Lena interfluve. An assessment is made of the main (preferred) and secondary ecological functions of vegetation within the geosystems. We demonstrate their changes with respect to native (reconstructed) vegetation. 相似文献
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Two zones of seismicity (ten events with M w = 7.0–7.7) stretching from Makran and the Eastern Himalaya to the Central and EasternTien Shan, respectively, formed over 11 years after the great Makran earthquake of 1945 (M w = 8.1). Two large earthquakes (M w = 7.7) hit theMakran area in 2013. In addition, two zones of seismicity (M ≥ 5.0) occurred 1–2 years after theMakran earthquake in September 24, 2013, stretching in the north-northeastern and north-northwestern directions. Two large Nepal earthquakes struck the southern extremity of the “eastern” zone (April 25, 2015, M w = 7.8 and May 12, 2015, M w = 7.3), and the Pamir earthquake (December 7, 2015, M w = 7.2) occurred near Sarez Lake eastw of the “western” zone. The available data indicate an increase in subhorizontal stresses in the region under study, which should accelerate the possible preparation of a series of large earthquakes, primarily in the area of the Central Tien Shan, between 70° and 79° E, where no large earthquakes (M w ≥ 7.0) have occurred since 1992. 相似文献
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