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991.
漂浮的冰架是气候变化的敏感指示物(Mercer,1978)。海洋的轻微变暖现象可以有效地减少冰架的体积。过去和现在建立的漂浮冰架下面的环流模式对于了解全球变暖对现今冰架的作用以及对全球海洋环流和气候的后期效应是至关重要的信息。 相似文献
992.
In order to generate well-based design decisions on reinforcement of landslide slopes and road embankment slopes, a system of combined geotechnical analysis of geological conditions is suggested which includes topographic and geophysical survey, and laboratory studies of soils using infra-red spectroscopy methods. Calculations of slopes' deflected modes are carried out with taking into account elastic and elasto-plastic behavior of soil, and the presence of supporting man-made constructions. Results of the application of the system suggested may be used as criteria for the classification of landslide slopes along permanent ways according to the degree of danger when used for transportation. 相似文献
993.
Barbara L. Sherriff Kristin A. Salzsauler Stephanie Simpson Nikolay V. Sidenko Jamie VanGulck 《中国地球化学学报》2006,25(B08):29-30
Local water contamination by arsenic can be caused by gold mining activities as in Snow Lake, Manitoba. This project was to f'md the source (s) and pathways of the arsenic contamination and describe arsenic attenuation in ground and surface water. The project was initiated because arsenic concentrations average 16.0 mg/L in one groundwater monitoring well (MW17). One potential source of arsenic is the 50 year-old Arsenopyrite Residue Stockpile (ARS), 100 m upgrade of MW17. Between 1948 and 1959, 250000 tons of cyanide treated, arsenopyrite concentrate were stored in a waste rock impoundment, which was left open until 2000 when it was capped with layers of waste rock, clay and silt to minimize water infiltration and the oxidative release of arsenic. 相似文献
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997.
本文试图以伊丽莎白港为例分析南非城市的法定种族隔离的形成过程。在1950年——1985年间,这个实有不公正种族隔离的殖民地城市,实际上已发展成为由政府策划者自认的不同人种的完全隔离区。土地使用条例的限制和人口流动对城市的外观和组织结构产生了深刻的影响,并必将严重影响到未来的规划。 相似文献
998.
Manganese nodules collected from the North Penrhyn Basin are characterized by low content of Mn and Fe, medium content of Ni and Cu , and medium Mn / Fe ratios . The average content of Ni plus Co is 1.11% , maximum 1.89% . Ni content slightly exceeds the Cu content in the nodules. Ni and Cu are strongly correlated with Mn , whereas Co is strongly correlated with Fe . Nodules containing Ni+Cu+Co near or in excess of 1% are rich in Mn and have a high Mn/Fe ratio. Those with highest content of Ni+Cu+Co are concentrated at or near the carbonate compensation depth . Nodules metal contents vary with latitude and have a reciprocal relationship with abundance. Contents of Mn, Ni, Cu and Ni+Cu+Co are high in nodules found at 2 - 6°S and vary decreasingly toward 1°N and 12°S , whereas Co content varies increasingly from 2°S towards 12°S. Nodule compositional variations with latitude are controlled by biological productivity, carbonate compensation depth , sedimentation rate, and bottom current. 相似文献
999.
The relationship between the all-India summer monsoon rainfall and surface pressure over the Indian region has been examined to obtain a useful predictor for the monsoon rainfall. The data series of all-India monsoon rainfall and the mean pressures of three seasons before and after the monsoon season as well as the winter-to-spring pressure tendency (MAM-DJF) at 100 stations for the period 1951-1980 have been used in the analysis.The all-India monsoon rainfall is negatively correlated with the pressure of the spring (MAM) season preceding the monsoon and winter-to-spring seasonal difference as pressure tendency (MAM-DJF), at almost all the stations in India, and significantly with the pressures over central and northwestern regions. The average mean sea level pressure of six stations (Jodhpur, Ahmedabed, Bombay, Indore, Sagar and Akola) in the Western Central Indian (WCI) region showed highly significant (at 1% level) and consistent CCs of-0.63 for MAM and -0.56 for MAM-DJF for the period 1951 - 1980. T 相似文献
1000.
A.D.谢格洛夫 《大地构造与成矿学》1989,13(1):35-36
<正> 过去几十年,成矿学有很大的进展,这种说法虽然不会有人反对。取得这种进展的原因是,我们在苏联领域上,研究了以内生矿床为主矿床的分布规律,发现了若干新的矿区和矿省,并且取得了成就。但是,在过去几年,对成矿学研究的兴趣略有减少,这也是显而易见的,原因可能很多,其中至少三个原因是大家都知道的。第一个原因是:我们曾制定出区域成矿分析的一般理论原则,后来在50—60年代末对其作了改进,根据这些原则编了成矿规律 相似文献