多宝山矿田的地面波谱研究及其在铜矿预测中的应用

根据矿田内岩矿地质波谱与ＴＭ图象亮度的线性相关关系，论述了多宝山铜矿田内矿床的地面波谱特征，地空相关模型及ＴＭ数据的地空相关分析方法，在此基础上讨论了其在铜矿预测中的应用效果。     

地震CT及其地质解释

在金川公司龙首矿东采区1 280中段井下500m深的巷道中应用地震CT技术进行寻找深部隐伏矿体的实验。波速图像表明,研究区内中西部有一高速异常区,推断为花岗岩体和含矿的超基性侵入岩体。区内还有一个横贯测区中央近东西走向的低速断裂带。这些推断结果为后期的钻探和巷道开掘所证明。     

RS和GIS结合的初步尝试

通过对航空遥感图像物体特征（色调、形状、大小、阴影、纹理及其相互关系）的提取，采用人机交互和自动识别的方法进行遥感航片的综合分析和利用，是合肥市规划与建设管理信息系统的一个重要内容。ＡＲＣ／ＧＲＩＤ模块的优势在于一对于栅格数据进行显示和查询；对于栅格数据进行算术、逻辑、关系、赋值等操作；对数据进行管理；其分析功能很强，可进行环境分析、社会分析、水文分析、经济分析；建立模型。通过图象分类处理，可将城市绿化、江河、城市主干道、建筑物分类，并对城市绿化进行区域统计，对江河、日照进行分析和对所分割的地块进行检索分析     

Electric Field Effects on Animals:Mechanism of Seismic Anomalous Animal Behaviors (SAABs)

Electric field effect on animals has been studied to investigate its relation with seismic anomalous animal behaviors(SAABs)in China.Freshwater eel,crucian carp,catfish,and soft-shelled turtle responded to the threshold electric field of 1-10 V/m,while duck,goose,cat,sheep,pig,dog,and chicken all responded to the ground electric field of about tens of V/m,depending on the species as well as on individuals.Most of the behaviors caused by electric field were similar to those reported as SAABs such as alignment,sudden movement,panic,and convulsion.The intensity of electric field due to a major earthquake would have been over these threshold values.Numerical estimation based on an electromagnetic model of a fault has been made to induce SAABs as electric shocks to pulsed electric fields in electro-physiology.The seismic electric signals(SES)intensity might be estimated from the observation of SAABs.     

Estimation of groundwater evaporation and salt flux from Owens Lake, California, USA

Groundwater evaporation and subsequent precipitation of soluble salts at Owens Lake in eastern California have created one of the single largest sources of airborne dust in the USA, yet the evaporation and salt flux have not been fully quantified. In this study, we compare eddy correlation, microlysimeters and solute profiling methods to determine their validity and sensitivity in playa environments. These techniques are often used to estimate evaporative losses, yet have not been critically compared at one field site to judge their relative effectiveness and accuracy. Results suggest that eddy correlation methods are the most widely applicable for the variety of conditions found on large playa lakes. Chloride profiling is shown to be highly sensitive to thermal and density-driven fluxes in the near surface and, as a result, appears to underestimate yearly groundwater evaporation. Yearly mean groundwater evaporation from the playa surface estimated from the three study areas was found to range from 88 to 104 mm year⁻¹, whereas mean evaporation from the brine-covered areas was 872 mm year⁻¹. Uncertainties on these mean rates were estimated to be ±25%, based on comparisons between eddy correlation and lysimeter estimates. On a yearly basis, evaporation accounts for approximately 47 × 10⁶ m³ of water loss from the playa surface and open-water areas of the lake. Over the playa area, as much as 7.5 × 10⁸ kg (7.5 × 10⁵ t) of salt are annually concentrated by evaporation at or near the playa surface, much of which appears to be lost during dust storms in area.     

Optimal weighting in the finite difference solution of the convection-dispersion equation

Oscillation and numerical dispersion limit the reliability of numerical solutions of the convection-dispersion equation when finite difference methods are used. To eliminate oscillation and reduce the numerical dispersion, an optimal upstream weighting with finite differences is proposed. The optimal values of upstream weighting coefficients numerically obtained are a function of the mesh Peclet number used. The accuracy of the proposed numerical method is tested against two classical problems for which analytical solutions exist. The comparison of the numerical results obtained with different numerical schemes and those obtained by the analytical solutions demonstrates the possibility of a real gain in precision using the proposed optimal weighting method. This gain in precision is verified by interpreting a tracer experiment performed in a laboratory column.     

Extreme value theory based on the r largest annual events: a robust approach

In Smith (1986, J. Hydrol. 86, 27–43), a family of statistical distributions and estimators for extreme values based on a fixed number r > = 1 of the largest annual events are presented. The method of estimation was numerical maximum likelihood. In this paper, we consider the robust estimation of parameters in such families of distributions. The estimation technique, which is based on optimal B-robust estimates, will assign weights to each observation and give estimates of the parameters based on the data which are well modeled by the distribution. Thus, observations which are not consistent with the proposed distribution can be identified and the validity of the model can be assessed. The method is illustrated on Venice sea level data.     

The identifiability of parameters in a water quality model of the Biebrza River, Poland

The identifiability of model parameters of a steady state water quality model of the Biebrza River and the resulting variation in model results was examined by applying the Monte Carlo method which combines calibration, identifiability analysis, uncertainty analysis, and sensitivity analysis. The water quality model simulates the steady state concentration profiles of chloride, phosphate, ammonium, and nitrate as a function of distance along a river. The water quality model with the best combination of parameter values simulates the observed concentrations very well. However, the range of possible modelled concentrations obtained for other more or less equally eligible combinations of parameter values is rather wide. This range in model outcomes reflects possible errors in the model parameters. Discrepancies between the range in model outcomes and the validation data set are only caused by errors in model structure, or (measurement) errors in boundary conditions or input variables. In this sense the validation procedure is a test of model capability, where the effects of calibration errors are filtered out. It is concluded that, despite some slight deviations between model outcome and observations, the model is successful in simulating the spatial pattern of nutrient concentrations in the Biebrza River.     

Observations of particle movement in a monitoring well using the colloidal borescope

The colloidal borescope consists of a set of lenses and miniature video cameras capable of observing natural particles in monitoring wells. Based on field observations of these particles, it appears possible to measure in situ groundwater velocity in a well bore. Field observations have shown that directional measurements using the colloidal borescope are generally in good agreement with expected flow directions. However, the magnitude of flow velocity is higher compared with values based on conventional test methods. High relative flow velocities, even after correction factors have been applied to compensate for well bore effects, are believed to be due to preferential flow zones in the surrounding aquifer. Low flow zones exhibit swirling multidirectional flow that does not allow for a linear velocity measurement. Consequently, groundwater flow velocities measured by the colloidal borescope in heterogeneous aquifers will be biased toward the maximum velocity values present in the aquifer. A series of laboratory experiments was conducted to assess the reliability of the instrument. Based on this work, a seepage velocity correction factor ( ) of 1–4 was found for quantifying groundwater seepage velocity in the adjacent aquifer from observations in a well bore. Laboratory measurements also indicate that preferential flow in the surrounding aquifer dominates flow in the well. Results of this work suggest the possibility of quantifying higher-flow velocities associated with preferential flow zones in the subsurface.