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Eyl has the unique desultory-weak or gap seismic reflection structure as its one of the most important characteristics. It is very important to clarify sedimentary characteristics and its origin for Yitong Graben and its sedimentary facies and tectonic evolution. On the basis of the research of core analyses, well logging data analyses, sedimentary facies analyses and seismic reflection structure analyses, the authors have concluded the sedimentary characteristics of Eyl, and have carried out Eyl sedimentary environments and its origin. The result shows that Eyl desultory-weak or gap seismic reflection may be a series of small scale secondary sediment fans superimposition.  相似文献   
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This study utilizes ANSYS to establish FEM's model of metamorphic core complex, and used thermal-structure analysis to simulate metamorphic core complex's temperature field and stress field. The meta- morphic core complex formation mechanism is discussed. The simulation results show that the temperature field change appearing as the earth surface' s temperature is the lowest, and the temperature of metamorphic core complex' s nucleus is the highest. The temperature field is higher along with depth increase, and the stress field change appearing as the biggest stress occurs in the nucleus. The next stress field occurs at the top of the cover.  相似文献   
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This paper describes a GIS-based spatial analysis method that combines qualitative analysis and quantita-tive analysis to characterize land-use patterns and predict the trend of future land-use changes in Halzhu District ofGuangzhou City, China. Spatial technique is introduced to manage land-use data and derive information of land-usechanges. Through the case study for the selected area, it is demonstrated that the method and technique introduced in thepaper can be effectively utilized for the analysis of urban land-use changes. Based upon this analysis, the paper also pro-vides discussions and recommendation on urban land-use planning, urban planning and land management. Both land-usemaps of Haizhu District of Guangzhou in 1995 and 1997 and the remote sensing images of 1999 are utilized in the cur-rent research. It is convenient to get various statistic data and to combine attribute data with spatial data so as to analyzeland-use changes in a geographic context, which is especially suitable for the need of urban construction department, ur-ban management department and urban planning department.  相似文献   
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同志们 :全区国土资源工作会议和全区地矿经济工作会议历时两天半 ,受到自治区人民政府和人大的高度重视 ,区直有关部门的同志也参加了会议 ,对此 ,我代表厅党组向他们表示衷心的感谢。下面我讲 4点意见。1 会议的基本情况这次国土资源工作会议和地矿经济工作会议一起套开 ,不仅形式新 ,而且说明了国土资源工作与地勘工作两者之间的密切联系。两天的会开得很紧张 ,内容也很丰富。王汉民副主席作了重要讲话 ,我传达学习了全国国土资源厅局长会议精神并代表局党组作了地矿经济工作报告 ,杨政中厅长代表厅党组作了国土资源工作报告。大会后 ,…  相似文献   
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The changes of taxonomical composition of the Late Jurassic- Early Cretaceous palynofloras are revealed, in the upper stream of Bureya River in Bureya Basin. The palynofloras are dominated as follows: the Berriasian one by ferns (Cyatheaceae, Dicksoniaceae, Osmundaceae), Classopollis and bisaccate pollen; the Valanginiar-Hauterivian one by ferns (Cyatheaceae, Dicksoniaceae), Ginkgocycadophytus and bisaccate pollen; the Barremian one by ferns (Cyatheaceae, Dicksoniaceae); the Aptian one by ferns (Cyatheaceae, Dicksoniaceae, Gleicheniaceae) and Ginkgocycadophytus; and the Albian one by ferns (Schizaeaceae) and bisaccate pollen. In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   
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