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Tony Waltham 《Geology Today》2001,17(1):22-24
A cold geyser appears to be a contradiction in terms. But a combination of carbon dioxide, effervescing groundwater and a fortuitous oil exploration well can create a very spectacular water fountain. 相似文献
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Tony Maxworthy 《Planetary and Space Science》1984,32(8):1053-1058
We present new measurements of the velocity field in the neighborhood of the high-speed jet located at approx. 24° N latitude in the Jovian atmosphere. The maximum zonal velocity is found to be 182 ± 10 m s?1 located at 23.7 ±0.2° N and representing the largest velocity measured on the planet. The distinctive cloud markings found close to this latitude are discussed and possible dynamical consequences presented. 相似文献
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The processes of stormflow generation were studied in a hill pasture catchment near Hamilton, New Zealand. Although rainfall was relatively evenly distributed throughout the year, stormflow was highly seasonal and over 65 per cent occurred during the winter. Three main processes contributing to stormflow were identified which could be related to soil type and physiographic position. On gleyed soils derived from rhyolitic colluvium, saturation overland flow was the dominant process. Hydrographs from ‘Whipkey’ throughflow troughs also indicated that there was a subsurface response (saturated wedge) from this soil type. On steeper convex slopes, more permeable soils were derived from weathered greywacke. The presence of ephemeral springs on the hillslopes and direct observation during storm events indicated that storm runoff was generated as return flow from this soil. It was noted that nitrate concentrations from subsurface sources were 5–10 times higher than surface runoff. This difference in concentration was utilized in a chemical mixing equation which partitioned stormflow sources. This was compared with the stormflow predicted from rain falling on to saturated areas. There was good agreement between the two models for winter-spring events with respect to the volumes of surface runoff predicted, however the saturated areas model underestimated total stormflow. The results of the study are briefly discussed in terms of the potential for water quality management. 相似文献
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J. H. Hull 《地学学报》1989,1(6):524-529
This paper reviews the role of environmental geology, and the practice of environmental geology mapping, in the context of the geological, geophysical and geochemical factors which are relevant to human activity and safety.
It is concluded that informed planning policies for the offshore areas are necessary. These would allow mutually acceptable and sensible exploitation of all natural resources, engineering and military developments and recreational uses, and would also take account of natural and man-made hazards to such activities. The policies would follow from multidisciplinary, systematic, environmental studies involving international cooperation.
The imperative for the earth-science practitioner to remain sensitive to the requirements of the users of such information is recognized, as is the need to communicate unambiguously. It is concluded that geologists should look increasingly from the past to the future. 相似文献
It is concluded that informed planning policies for the offshore areas are necessary. These would allow mutually acceptable and sensible exploitation of all natural resources, engineering and military developments and recreational uses, and would also take account of natural and man-made hazards to such activities. The policies would follow from multidisciplinary, systematic, environmental studies involving international cooperation.
The imperative for the earth-science practitioner to remain sensitive to the requirements of the users of such information is recognized, as is the need to communicate unambiguously. It is concluded that geologists should look increasingly from the past to the future. 相似文献
39.
A spectrum scanning Stokes polarimeter 总被引:1,自引:0,他引:1
40.
Economic and social development indicators suggest that the small West African state of Sierra Leone is among the poorest
countries in the world. Sierra Leone’s economy and quality of life deteriorated rapidly during a decade of political instability
and civil war in the 1990s, when many people fled their homes and abandoned their livelihoods due to the rebel insurgency.
This paper examines the post-war reconstruction scenario in Sierra Leone and presents recent evidence from two rural communities
in the Eastern Province that were badly affected by the conflict. The paper considers the links between the farming and diamond
mining sectors, which, despite severe dislocation during the conflict period, have proved to be remarkably resilient. It is
argued that seasonal labour mobility associated with this dual economy has not only continued to be a key ingredient in sustaining
livelihood portfolios, but is actually an essential pre-condition for the creation of an enabling environment for sustainable
post-conflict return.
相似文献
Tony BinnsEmail: |