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111.
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   
112.
In this paper, an inverse mapping is used to transform the previously-derived analytical solutions from a local elliptical coordinate system into a conventional Cartesian coordinate system. This enables a complete set of exact analytical solutions to be derived rigorously for the pore-fluid velocity, stream function, and excess pore-fluid pressure around and within buried inclined elliptic inclusions in pore-fluid-saturated porous rocks. To maximize the application range of the derived analytical solutions, the focal distance of an ellipse is used to represent the size of the ellipse, while the length ratio of the long axis to the short one is used to represent the geometrical shape of the ellipse. Since the present analytical solutions are expressed in a conventional Cartesian coordinate system, it is convenient to investigate, both qualitatively and quantitatively, the distribution patterns of the pore-fluid flow and excess pressure around and within many different families of buried inclined elliptic inclusions. The major advantage in using the present analytical solution is that they can be conveniently computed in a global Cartesian coordinate system, which is widely used in many scientific and engineering computations. As an application example, the present analytical solutions have been used to investigate how the dip angle of an inclined elliptic inclusion affects the distribution patterns of the pore-fluid flow and excess pore-fluid pressure when the permeability ratio of the elliptic inclusion is of finite but nonzero values.  相似文献   
113.
The correlation between the long-term intensity variations of cosmic rays at neutron monitor energies and the LDE index measure of solar flares with long-lasting soft X-ray emissions is reported. Three subsequent solar cycles, 20–22, are taken into account and half-monthly data are analyzed. Possible explanation of this correlation is discussed in terms of the recent concepts of cosmic-ray modulation, in particular with merged interaction regions affecting the cosmic-ray intensity.  相似文献   
114.
The Rozvadov Pluton is a complex of mainly Variscan granitoid rocks situated near the Bohemian-Bavarian border between Bärnau, Tachov, Rozvadov and Waidhaus, 25 km ESE of the KTB site. Five mappable units can be distinguished, which intruded as folows: (1) slightly deformed leucocratic meta-aplite/metapegmatite dykes with garnet and tourmaline; (2) a complex of cordierite-bearing granitoids, which have been divided into three facies (a) biotite granite with cordierite (at the margin of the complex), (b) biotite-cordierite granite and (c) cordierite tonalite (in the centre of the complex; (3) fine-grained biotite granite of the Rozvadov type with associated pegmatite bodies; (4) two-mica Bärnau granite; and (5) geochemically specialized albite-zinnwaldite-topaz granite (Kríový kámen/Kreuzstein granite) with indications of Sn-Nb-Ta mineralization and associated phosphorus-rich pegmatite cupolas. Rare earth element data suggest that meta-aplite/pegmatite dykes are the result of a batch partial melting process, whereas the compositional variation of the other rock types was mainly controlled by fractional crystallization. The genesis of the cordierite granitoid suite is best explained in terms of a batch melting of metapelitic source followed by crystallization of a cordierite-rich cumulate and K-feldspar enriched melt. The leucocratic pluton constituents — the meta-aplites and the Bärnau and Kíový kámen granites are rich in phosphorus (0.5–0.8%). The main carriers of phosphorus are alkali feldspars, especially K-feldspar (up to 0.8% P2O5). The presence of P-rich leucocratic granites is one of the features distinguishing the Variscan granitoids within the Moldanubian zone from the nearly contemporaneous granitoids in the Saxothuringian zone.  相似文献   
115.
116.
本对斜交型扰动不稳定谱点的分布做了理论分析,得到了该谱点分布的半圆定理一该谱点分布在复一面上以原点为圆心以R0为半径的上半平面上,同时还对该不稳定增长率的上界作了估计。发现水平永度越小,模式顶越高则该估计值越大;垂直风切变的增大和纬度的增高对该增长率的增大有正贡献;当层结稳定度减小时,最大增长率随相对最大增长率得增大而减小。  相似文献   
117.
通过引人泊松括号,分析了无限维Hamilton的性质,并将其推广到广义Hamilton系统,且从理论和实用角度讨论了这类广义Hamilton系统的辛格式构造问题,从而为辛几何算法在一般的时间发展方程的数值求解提供新的具体途径。  相似文献   
118.
In this paper, MSMR geophysical products like Integrated Water Vapour (IWV), Ocean Surface Wind Speed (OWS) and Cloud Liquid Water (CLW) in different grids of 50, 75 and 150 kms are compared with similar products available from other satellites like DMSP-SSM/I and TRMMTMI. MSMR derived IWV, OWS and CLW compare well with SSM/I and TMI finished products. Comparison of MSMR derived CLW with that derived from TMI and SSM/I is relatively in less agreement. This is possibly due to the use of 37 GHz in SSM/I and TMI that is highly sensitive to CLW, while 37 GHz channels are not available on MSMR. Monthly comparison of MSMR geophysical products with those from TMI is all carried out for climatological purpose. The monthly comparisons were much better compared to instantaneous comparisons. In this paper, details of the data analysis and comparison results are presented. The usefulness of the MSMR vis-à-vis other sensors is also discussed.  相似文献   
119.
The Skidaway River estuary is a tidally-dominated subtropical estuary in the southeastern USA surrounded by extensiveSpartina salt marshes. Weekly smapling at high and low tide began in 1986 for hydrography, nutrients, chlorophylla, particulate matter, and microbial and plankton biomass and composition; hydrographic and nutrient data during 1986–1996 are reported here. Salinity varied inversely with river discharge and exhibited variability at all time scales but with no long-term trend. Water temperature typically ranged over 25°C and was without apparent long-term frend. Seasonal cycles in concentrations of NO3, NH4, PO4, Si(OH)4, and DON were observed, with annual maxima generally occurring in late summer. Superimposed on seasonal cycles, all five nutrients exhibited steady increases in minimum, mean, and maximum concentrations; mean concentrations increased c. 50–150% during the decade. Nutrient concentrations were highly correlated with water temperature over the ten-year period, but weakly related to salinity and discharge. Nutrients were strongly correlated with one another, and the relative ratios among inorganic nutrients showed little long-term trend. Correlations among temperature and nutrient concentrations exhibited considerable inter-annual variability. Major spikes in organic and inorganic nutrient concentrations coincided with significant rainfall events; concentrations increased hyperbolically with rainfall. Although pristine compared to more heavily impacted waterways primarily outside the region, residential development and population density have been increasing rapidly during the past 15–20 years. Land use is apparently altering nutrient loading over the long-term (months-years), and superimposed on this are stochastic meteorological events that accelerate these changes over the short term (days-weeks).  相似文献   
120.
In order to understand the processes of land surface-atmosphere interaction over desertification area, it is indispensable to utilize of satellite remote sensing. Two scenes of Landsat TM were used to produce a set of maps of surface reflectance, MSAVI, vegetation coverage, surface temperature, net radiation, soil heat flux, sensible heat flux and latent heat flux. Statistical analysis based on these maps revealed some quantitative significant land surface characteristics. Future developments of the method are also discussed.  相似文献   
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