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The elastic and density properties of rocks of the Shamakha-Ismailly seismogenic blocks are studied by the ultrasonic pulse method in quasi-hydrostatic high pressure apparatuses. An attempt is made to more accurately determine the upper crustal lithology of these blocks. The observed values of the elastic and density characteristics of the rocks at high pressures suggest that the upper layers in the Ismailly and Shamakha blocks can consist of sedimentary carbonate rocks such as marls, sandstones, mudstones, and limestones. The middle layers apparently consist of volcaniclastic rocks: lithoclastic tuffs, andesites, etc. The lower layer (basement) in both blocks is likely composed of basic rocks such as basalts, trachybasalts, etc. According to the values of elastic wave velocities and densities, gabbroid rocks may compose the fourth layer of the Buinuz intrusion, identified from seismic data.  相似文献   
2.
Using Shen’s method (Shen et al., 1996), deformations of the Earth’s crust in Azerbaijan were studied based on GPS measurements. For estimating the rate of deformation, we used the field of velocity vectors for Azerbaijan, Iran, Georgia, and Armenia that were derived from GPS measurements during 1998–2012. It is established that compression is observable along the Greater Caucasus, in Gobustan, the Kura depression, Nakhchyvan Autonomous Republic, and adjacent areas of Iran. The axes of compression/contraction of the crust in the Greater Caucasus region are oriented in the S-NE direction. The maximum strain rate (approximately 200 × 10?9 per annum) is documented in the zone of mud volcanism at the SHIK site (Shykhlar), which is marked by a sharp change in the direction of the compression axes (SW-NE). It is revealed that the deformation field also includes the zones where strain rates are very low approximating 5 × 10?9 per annum. These zones include the Caspian-Guba and northern Gobustan areas, characterized by extensive development of mud volcanism. The extension zones are confined to the Lesser Caucasus and are revealed in the Gedabek (GEDA) and Shusha (SHOU) areas, as well as in the zone located between the DAMO and PIRM sites (Iran), where the deformation rate amounts to 100 × 10?9 per annum. It is concluded that the predominant factor responsible for the eruption of mud volcanoes is the intensity of gas-generation processes in the earth’s interior, while deformation processes play the role of a trigger. The zone of the epicenters of strong earthquakes is correlated to the gradient zone in the crustal strain rates.  相似文献   
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青藏高原处于东亚季风、印度季风和西风环流交互作用区.末次冰消期以来,太阳辐射对该地区的古气候环境产生了重要影响,湖泊随着季风系统的变化发生了明显的水位升降,对湖岸阶地的形成起到了直接作用.本项研究重建了青藏高原东北缘冬给错纳湖湖岸阶地记录的湖面波动历史,试图了解青藏高原季风系统演变过程.通过湖泊北岸265 cm厚湖岸阶地沉积物粒度、碳酸盐、矿物、元素和介形虫古环境指标,结合OSL年代模式,分析表明在约10. 2 ka B. P.之前水体较浅;约10. 2~9. 0 ka B. P.湖面开始上升,气候凉湿;9. 0~8. 5 ka B. P.为印度季风强盛期,湖面明显上升,降雨量增高、温度上升;8. 5~7. 9 ka B. P.湖面降低与气候变冷有关;7. 9~7. 0 ka B. P.印度季风开始减弱,气温、降雨下降,但有效湿度较大,湖面降低;7. 0~6. 1 ka B. P.湖面上升可能与低蒸发作用有关,印度季风仍然影响该地区;6. 1~5. 2 ka B. P.,印度季风衰退,气候逐渐变冷、降雨量减小、水体变浅;5. 2~4. 6 ka B. P.气候冷干,有效湿度减小,湖面进一步下降;4. 6 ka B. P.至今气候干冷,东亚季风衰退,湖面下降,期间也可能受西风环流影响而有短暂的降雨增加时期.  相似文献   
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The density ρ of Caspian Sea waters was measured as a function of temperature (273.15–343.15) K at conductivity salinities of 7.8 and 11.3 using the Anton-Paar Densitometer. Measurements were also made on one of the samples (S = 11.38) diluted with water as a function of temperature (T = 273.15–338.15 K) and salinity (2.5–11.3). These latter results have been used to develop an equation of state for the Caspian Sea (σ = ±0.007 kg m−3)
where ρ0 is the density of water and the parameters A, B and C are given by
Measurements of the density of artificial Caspian Sea water at 298.15 K agree to ± 0.012 kg m−3 with the real samples. These results indicate that the composition of Caspian Sea waters must be close to earlier measurements of the major components. Model calculations based on this composition yield densities that agree with the measured values to ± 0.012 kg m−3. The new density measurements are higher than earlier measurements. This may be related to a higher concentration of dissolved organic carbon found in the present samples (500 μM) which is much higher than the values in ocean waters (~65 μM).  相似文献   
6.
By complex analysis of GPS velocities, seismicity, fractal dimensions of the spatial distribution of seismic epicenters, focal mechanisms of the earthquakes, and stress state of the Earth’s crust, four seismic zones (Balaken-Zagatala, Sheki-Gabala, Shamakhy-Ismailly, and Absheron) are revealed within the southern slope of the Greater Caucasus. The suggested method can be used as a criterion in seismotectonic zoning; it could also be useful in the assessment of seismic hazards in the collision zones.  相似文献   
7.
Data from 40 meteorological stations have been used in investigating the changes of the precipitation regime on the territory of Azerbaijan during 1991–2006. It is shown that ubiquitous warming in most of the territory of the Republic is accompanied by a decrease of the annual mean amount of atmospheric precipitation, mainly through a reduction in precipitation during a warm period (April–October).  相似文献   
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