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71.
应用直流电法仪在井下进行了工作面巷道底板电测深和掘进头超前探测,查清了工作面底板水层的富水性和掘进头前头的地质构造及含水情况。目前,大部分探测结果已得到生产实践的证实。 相似文献
72.
K. S. Voudouris N. J. Lambrakis G. Papatheothorou P. Daskalaki 《Mathematical Geology》1997,29(1):43-59
R- andQ-mode factor analysis is applied to 51 groundwater samples collected from wells drilled in the Plio-Pleistocene aquifers of
NW Achaia, Greece. The purpose ofR- andQ-mode factor analysis application is to identify (i) the regional groundwater flow pattern, and (ii) the deterioration of
groundwater quality. Sixteen hydrogeological parameters are used in order to examine their importance and to provide significant
insight into their correlations. In theR-mode factor analysis, a six-factor model is suggested which can explain more than 77.5% of the total variance. The contribution
of each factor at every site (factor scores) also is computed. Maps are constructed showing the geographical distribution
of the factor scores. From these maps, the high salinity areas are delineated (seawater intrusion, possible appearance of
halite layers) and the areas with elevated contribution of karastic-water are defined. Using theQ-mode correspondence analysis the meaning of the electrical conductivity as the most important variable in groundwater quality
characterization is demonstrated. 相似文献
73.
坡地系统土壤侵蚀定量评价方法 总被引:6,自引:0,他引:6
区域性土壤侵蚀的定量评在涉及到泥沙输移的非连续性难题和众多的非确定性因素,目前应用较普遍的小区定量难以适用。所提出的定量评价方法是利用GIS技术、模糊数学、将以分布参数为特征的区域坡地系统划分成若干类具有集中参数特征的基本侵蚀单元,结合USLE方程来模拟空间上不同侵蚀背景条件下土壤侵蚀的强度,并可以确定影响土壤侵蚀的主要因子及其排序,该方法适用性强,可用于不同空间尺度的土壤侵蚀定量评价。 相似文献
74.
本文论述了冀中坳陷-黄骅坳陷馆陶组热储砂岩、底部砾岩、砂砾岩的发育、孔隙度及热水水质的差异性,对热储出水特征进行了探讨,提出了馆陶组热储成井的基本条件,对冀中坳陷-黄骅坳陷馆陶组热储成井具有一定的指导意义。 相似文献
75.
76.
地理信息系统是国家信息资源的重要组成部分。地理信息技术经过20多年的飞速发展,已经渗透到社会各个方面,促使人们生产、生活方式发生深刻变化。我国地理信息系统(GIS)技术正在向信息化方向发展,并正在逐步成为面向21世纪的支柱产业一信息产业的重要组成部分。国际GIS技术的发展趋势,主要体现在两个方面,一是综合,二是分化。从空间信息处理的角度看,可将GIS的发展分为空间信息的管理、分析、模拟和调控四个阶段。GIS技术的应用表现在一是面向大型项目,二是面向公众。 相似文献
77.
Web Use in Geographical and Environmental Education: An International Survey at the Primary and Secondary Level 总被引:2,自引:0,他引:2
This article aims to study Web use and Web-based co-operation and collaboration in geographical and environmental education
at the primary and secondary level around the world. Recent trends and future opportunities and challenges are taken into
account. The theoretical part of the study considers Web use and different forms of Web-based co-operation. Web use and co-operation
in education are classified as co-operative learning, collaborative learning or communal learning. Web use in geographical
and environmental education is noted to be growing in significance. Web-based co-operation at any level of intensity is associated
with many opportunities and challenges. The empirical part of this study involves a survey of geographical and environmental
education researchers in various countries about their views of Web use in education. The results of this survey indicate
that the Web in general finds minimal use in geographical and environmental education. As access to the Web is limited and
only some pupils can use it, co-operation, particularly collaborative learning on the Web, is still rare in geographical and
environmental education. The most often used application is e-mail. Researchers recognise the potential of the Web to enhance
local, national and international co-operation, and to facilitate a better understanding of geographical and environmental
issues at the grass-root level. Web-based learning can also help to increase and deepen the pupils' cultural understanding.
Before that, however, problems in access, costs and teacher training must be solved.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
78.
Sébastien J. Stemmler Stéphanie Loyaux-Lawniczak Jacques Berthelin 《Comptes Rendus Geoscience》2004,336(13):1171-1179
Iron-reducing activity of autochthonous bacteria from two temporary hydromorphic soils is evaluated by the study of iron reductive dissolution, as a function of water content. The release of ferrous iron in solution is coupled to the mineralization of soil organic carbon. Water soil saturation is not necessary for iron reductive dissolution, since the highest dissolution is obtained for a wet, but not water-saturated soil (100% of water holding capacity WHC), and dissolution is also very high in a soil at 75% WHC. To cite this article: S.J. Stemmler et al., C. R. Geoscience 336 (2004). 相似文献
79.
高坪-吉心段公路喀斯特工程地质综合勘察 总被引:1,自引:0,他引:1
以沪蓉国道主干线湖北省高坪-吉心段的喀斯特地质勘察工作为例,探讨喀斯特地区公路工程地质综合勘察的基本方法。在喀斯特地区运用遥感和地理信息技术技术、地质测绘、综合物探以及地质钻探等勘察手段,通过综合分析各种勘探成果,能够较准确地查明可溶岩的分布、喀斯特形态类型、分布规律、控制因素以及喀斯特水的赋存、分布和运移规律等,并根据不同的喀斯特地貌提出了有针对性的处理对策。通过不断的实践和经验总结。针对喀斯特工程地质问题合理运用综合工程勘察方法,能做出科学的分析评价,可以适应喀斯特区公路建设的需要,并且供今后在喀斯特地区修建公路时参考和借鉴。 相似文献
80.
About 70% of its land area as mountains and plateaus,China is the largest mountain countryin the world.Thanks to its vast territory (9.6 million km2),outstanding relief and varied climates,China boasts extremely plenty of ecosystems and landscapes.From south to north,it traverses almostall the temporal zones from tropical rainforest in the southernmost to frigid-temperate needle-leavedforest in the northernmost; from east to west,it sees a gradual transition fro humid forest landscape toextremely arid desert landscape; vertical change of landscapes is most striking owing to the existenceof many high mountains (above 6000-7000 m,e.g.,the Himalayas,the Kunlun,the Tianshan,theHengduan,etc.) and plateaus,especially the immense Tibetan Plateau (averagely 4500 m above sealevel).All of this give rise to the richness and diversity of ecosystems and landscape in China.Some ofthe ecosystems are endemic to China,e.g.,alpine desert and alpine steppe in the Tibetan Plateau.As aresult,China bears a great responsibility in the protection of global ecosystems and landscape. 相似文献