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21.
Singular physical or chemical processes may result in anomalous amounts of energy release or mass accumulation that, generally, are confined to narrow intervals in space or time. Singularity is a property of different types of non-linear natural processes including cloud formation, rainfall, hurricanes, flooding, landslides, earthquakes, wildfires, and mineralization. The end products of these non-linear processes can be modeled as fractals or multifractals. Hydrothermal processes in the Earth’s crust can result in ore deposits characterized by high concentrations of metals with fractal or multifractal properties. Here we show that the non-linear properties of the end products of singular mineralization processes can be applied for prediction of undiscovered mineral deposits and for quantitative mineral resource assessment, whether for mineral exploration or for regional, national and global planning for mineral resource utilization. In addition to the general theory and framework for the non-linear mineral resources assessment, this paper focuses on several power-law models proposed for characterizing non-linear properties of mineralization and for geoinformation extraction and integration. The theories, methods, and computer system discussed in this paper were validated using a case study dealing with hydrothermal Au mineral potential in southern Nova Scotia, Canada.  相似文献   
22.
综合气象观测系统业务运行综合评估技术研究   总被引:4,自引:0,他引:4  
孟昭林  李雁  陈挺  石城 《气象》2011,37(2):219-225
综合气象观测网运行监控系统是我国气象探测设备运行保障的实时业务系统.文章以装备技术保障工程理论为基础,按可靠性、维修性、保障性、业务性、经济性等多个范畴,从装备运行状态、装备性能参数、探测数据质量、通信传输、供应保障、维护维修等方面,提出了针对我国综合气象观测网中各类设备的运行、维护和保障等工作进行综合评估的技术方法,...  相似文献   
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24.
Na lidar observations of SSL during the past 5 years at a mid-latitude location (Wuhan, China, 31°N, 114°E) are reported in this paper. From 26 SSL events detected in about 230 h of observation, an SSL occurrence rate of 1 event/9 h at our location was obtained. This result, combined with that reported by Nagasawa and Abo (Geophys. Res. Lett. 22 (1995) 263) at Tokyo, Japan, reveals that the SSL occurrence can be relatively frequent at some mid-latitude locations. The statistical analyses of main parameters for the 26 SSL events were made, and the results were compared with those previously reported. By examining the corresponding data from a nearby ionosonde, it was found that there was a fairly good correlation between SSL and Es. Of the 18 pairs of SSL and Es events checked, 15 of SSL were accompanied by Es, and 8 pairs of them were correlated within 1 h in time and within 5 km in altitude. From the analyses of observed perturbations during SSL development, the role of dynamic processes of atmosphere in the SSL formations were emphasized.  相似文献   
25.
The lithospheric strike‐slip Altyn Tagh Fault has accommodated hundreds of kilometres of displacement between the Qaidam and Tarim blocks since its Eocene reactivation. However, the way the deformation is accommodated in the Qilian Shan and further east remains uncertain. Based on 360 km of north‐eastward migration of the relatively rigid Qaidam block along the Altyn Tagh Fault and 3D isovolumetric balancing of the crustal deformation within the Altyn Tagh Fault–Qilian Shan system, we demonstrate that 250 ± 28 km (43.8–49.4%) of N20E directed crustal shortening and an additional ~250–370 km of eastward motion of the Qilian Shan crust must be accounted for by strike‐slip faulting in the Qilian Shan and crustal thickening in the Qinling area, as well as by extension in the adjoining North China block graben systems.  相似文献   
26.
Wetlands of Northeast Asia and High Asia: an overview   总被引:3,自引:0,他引:3  
This review reports background information on wetlands in the Northeast Asia and High Asia areas, including wetland coverage and type, significance for local populations, and threats to their vitality and protection, with particular focus on the relationship of how global change influenced wetlands. Natural wetlands in these areas have been greatly depleted and degraded, largely due to global climate change, drainage and conversion to agriculture and silviculture, hydrologic alterations, exotics invasions, and misguided management policies. Global warming has caused wetland and ice-sheet loss in High Asia and permafrost thawing in tundra wetlands in Northeast Asia, and hence induced enormous reductions in water-storage sources in High Asia and carbon loss in Northeast Asia. This, in the long term, will exacerbate chronic water shortage and positively feed back global warming. Recently, better understanding of the vital role of healthy wetland ecosystems to Asia’s sustainable economic development has led to major efforts in wetland conservation and restoration. Nonetheless, collaborative efforts to restore and protect the wetlands must involve not only the countries of Northeast and High Asia but also international agencies. Research has been productive but the results should be more effectively integrated with policy-making and wetland restoration practices under future climatic scenarios.  相似文献   
27.
宁绍平原史前遗址、埋藏泥炭与中全新世海面变化   总被引:4,自引:0,他引:4  
史威  马春梅  焦锋  朱诚  王富葆 《海洋学报》2008,30(4):169-175
浙江萧山跨湖桥遗址的年代学证据表明[1-6],新石器时期宁绍平原西部距今8000a前后已有人类活动,较华东其他沿海平原区新石器时期人类活动的上限提早了近1000a。由于该区恰处于全新世最大海侵的敏感部位,遗址地层有可能反映最大海侵前后的海面变化状况;另一方面,继跨湖桥和下孙遗址遭受海侵[4-7]之后,时代较晚的河姆渡遗址出现在宁绍平原中部,这可能暗示此时本区已进入了一次海退阶段或相对低海面期。  相似文献   
28.
综合介绍了信息高速公路及国家空间信息基础设施的基本情况、地理科学的信息化和地理信息系统的发展趋势和特点,并说明了信息高速公路对地理科学信息化及地球科学研究及应用的影响。  相似文献   
29.
轴压下两体力学模型的转化条件及影响因素分析   总被引:1,自引:0,他引:1  
易成  朱红光  王洪涛  刘征  潘宏 《岩土力学》2011,32(5):1297-1302
接触界面的相互作用是影响工程稳定的重要因素,基于接触面两侧介质的实际受力状态,采用一体两介质力学模型与两体两介质力学模型加以描述。通过一体和两体模型试件的轴压破坏试验,分析了两种模型的力学响应的差异,并认为:一体两介质力学模型在符合一定条件情况下可以转变为两体两介质力学模型。此外,还对影响两种力学模型性能的参数进行了分析。提出对一体两介质力学模型力学性能产生影响的参量是低强度介质与高强度介质的静载极限强度比k以及两种介质之间的黏结力c;对两体两介质力学模型力学性能产生影响的主要参量除了k之外,尚有两种介质的断裂韧度比? 、体积比? 以及界面的粗糙程度  相似文献   
30.
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