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111.
Ribbon rocks are characterized by an alternation of millimeter-to centimeter-thick limestone and argillaceous deposits (marlstone or shale).The sedimentary processes and diagenetic characteristics of ribbon rocks might be critical to the formation of limestone conglomerates.According to detailed field measurement and laboratory analyses (thin section observation and XRD analysis),four types of ribbon rocks are classified,i.e.,limestone and marlstone couplet (L-M),limestone and shale couplet (L-S),thin-bedde...  相似文献   
112.
113.
  总被引:3,自引:0,他引:3  
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114.
Frequency of occurrence and dynamics of droughts in 20th century were studied based on the observational materials of 20 meteorological stations of Eastern Georgia. The periods with precipitation deficit were studied against the background of high temperatures. The drought intensity was assessed with the Selyaninov hydrothermal coefficient.  相似文献   
115.
Variations in the number of hot days, their frequency, intensity, and duration in Georgia are studied using observational data from 50 weather stations for the period of 1936-2013. The periods of the onset of hot days in the year and their maximum intensity in different physiographic conditions are identified. The zoning of Georgia was carried out according to the rate of changes in the number of hot days. The results enhance the understanding of climate change in Georgia under global warming conditions.  相似文献   
116.
An analysis of the statistical characteristics of the optical depth of suspended particulates was made in several parts of the visible spectrum as it is affected by meteorological conditions. The paper tests whether the association of the statistical characteristics of the spectral structure of visible radiation with meteorological parameters is strong enough to serve as part of the explanation for the onset of different states of atmospheric turbidity. Equations are derived that permit estimation of atmospheric optical conditions from meteorological data.  相似文献   
117.
On the observation data of 30 meteorological stations in Georgia during 1961–2008, occurrence frequency and dynamics are studied of the most hazardous light frosts registered during the freeze-free period. Occurrence frequency of minimum temperature during light frosts is studied along with the light frost areas. Dynamics of light frost occurrence frequency in the 20th century is considered.  相似文献   
118.
The dynamics of the occurrence frequency of extreme anomalies of monthly mean air temperature and its effect on precipitation and river water discharge in the 20th century are studied using weather observations at 40 stations and data on the hydrological regime of 34 rivers in Georgia.  相似文献   
119.
Created are the grid datasets of monthly mean and annual mean temperature as well of monthly, seasonal, and annual values of the total precipitation with the resolution of 25 km for the period of 1936–2011. The obtained datasets characterize the real picture of the spatial distribution of temperature and precipitation on the territory of Georgia; therefore, they are used for working out geoinformative maps of temperature and precipitation variations. Revealed are the areas and centers with different intensity of warming and cooling. It is found that the annual temperature and total annual precipitation averaged for the territory do not vary considerably under conditions of the global warming.  相似文献   
120.
基于四川省1980—2017年主要气象要素观测资料,运用ArcGIS空间分析法,分别探讨了气温、降水量和极端气候指数的年际空间变化特征;同时建立极端气候指标体系,结合熵权法、模糊综合评价法开展综合极端气候指数区划,最终完成1980—2017年四川省气候变化综合区划。研究表明:1980—2017年四川省极端气候事件的发生率呈上升趋势,从区域分布上大致表现为东高西低;根据四川省气温和降水量变化速率区划、综合极端气候指数区划,将四川省划分为6个气候变化区,其中,川东北地区综合气候变化速率最快。  相似文献   
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