桂北江南古陆南缘拗褶带中铅锌矿产成矿信息特征及预测标志

本文通过研究与总结前人成果基础上.对桂北江南古陆南缘拗褶带中铅锌矿进行成矿预测。文中侧重探讨了该带的成矿环境、典型矿床特征、控矿因素和地球物理、地球化学特征;综合地、物、化成矿信息.总结提出了7 条成矿预测标志:采用特征分析法对该带中的19个成矿单元进行资源定性预测评价,认为其铅锌矿资源潜力较大,有找矿前景。     

GB／T19000—ISO9000国家标准简介及在地勘单位贯彻中面临的间题

ＧＢ／Ｔ１９０００—ＩＳＯ９０００系列标准等同采用了国际通行的质量管理标准。贯彻该标准不仅能提高地勘单位质量管理水平、产品质量，也为地勘单位开展质量体系认证、产品质量认证提供技术依据，增强地勘单位参与国内、外市场竞争的能力。目前在贯标工作中制约因素主要有：地质成果形成特点及地质成果质量管理的特殊性、地质工作投入的减少及现有地质技术人员素质等。然而，贯标是我国经济体制改革深入的要求，是地勘队伍走出低谷、求生存和发展的基本手段。贯标和建立新的经济运行机制之间存在有相互依存、相互促进的关系。     

Spectrum characteristics of major ion concentrations at Wuhan sectoin of the Changjiang Rriver

Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang(Yangtze) River, etc. The fluctuations of Ca²⁺, Mg²⁺ and HCO ₃ ⁻ concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation (QBO). Na⁺, Cl⁻ SO ₄ ²⁻ have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river diseharge fluctuation accounts for 43.9%, 45.1%, 54.3%, 33.9%, 30.3% and 42.7% of the variance of Ca²⁺, Mg²⁺, HCO ₃ ⁻ , Na⁺, Cl⁻, SO ₄ ²⁻ , respectively, at Wuhan from 1962 to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data. Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 49671017). Biography: XIA Xing-hui(1971-), female, a native of Hunan Province, Ph. D. Her research interest includes environmental chemistry.     

Simulating daily soil water under foothills fescue grazing with the soil and water assessment tool model (Alberta,Canada)

Grazing is common in the foothills fescue grasslands and may influence the seasonal soil‐water patterns, which in turn determine range productivity. Hydrological modelling using the soil and water assessment tool (SWAT) is becoming widely adopted throughout North America especially for simulation of stream flow and runoff in small and large basins. Although applications of the SWAT model have been wide, little attention has been paid to the model's ability to simulate soil‐water patterns in small watersheds. Thus a daily profile of soil water was simulated with SWAT using data collected from the Stavely Range Sub‐station in the foothills of south‐western Alberta, Canada. Three small watersheds were established using a combination of natural and artificial barriers in 1996–97. The watersheds were subjected to no grazing (control), heavy grazing (2·4 animal unit months (AUM) per hectare) or very heavy grazing (4·8 AUM ha^?1). Soil‐water measurements were conducted at four slope positions within each watershed (upper, middle, lower and 5 m close to the collector drain), every 2 weeks annually from 1998 to 2000 using a downhole CPN 503 neutron moisture meter. Calibration of the model was conducted using 1998 soil‐water data and resulted in Nash–Sutcliffe coefficient (EF or R²) and regression coefficient of determination (r²) values of 0·77 and 0·85, respectively. Model graphical and statistical evaluation was conducted using the soil‐water data collected in 1999 and 2000. During the evaluation period, soil water was simulated reasonably with an overall EF of 0·70, r² of 0·72 and a root mean square error (RMSE) of 18·01. The model had a general tendency to overpredict soil water under relatively dry soil conditions, but to underpredict soil water under wet conditions. Sensitivity analysis indicated that absolute relative sensitivity indices of input parameters in soil‐water simulation were in the following order; available water capacity > bulk density > runoff curve number > fraction of field capacity (FFCB) > saturated hydraulic conductivity. Thus these data were critical inputs to ensure reasonable simulation of soil‐water patterns. Overall, the model performed satisfactorily in simulating soil‐water patterns in all three watersheds with a daily time‐step and indicates a great potential for monitoring soil‐water resources in small watersheds. Copyright © 2004 John Wiley & Sons, Ltd.     

BP神经网络在矿产资源评价中的应用

简述BP神经网络的基本原理,通过实例阐述BP神经网络在矿产资源GIS评价应用方法,提出注意事项及如何提高评价应用效果.     

安徽省淮北平原地下水环境与工作方向

安徽省淮北平原位于该省北部,平原西部阜阳市地面沉降中心最大沉降量1501mm,采水型地面沉降进一步扩大,推测平原西部地区已发生大范围的地面沉降.淮北平原区饮水型高氟地方病广布,地氟病区占全区总面积的40%.其中轻病村17942个,占病村总数79.5%;中度病村4529个,占20.0%;重病村148个,占病村总数0.65%.病区乡人口总数1344.4万人,占淮北平原总人口的66%.区域地下水水位持续下降,地下水质量不断劣化.本文通过对以上主要水环境问题的论述,提出了平原区今后工作方向的建议.     

刘店煤矿岩浆侵入与煤质特征初探

岩浆侵入是煤矿常见的构造现象之一,岩浆侵入后对煤层与煤质的影响也十分明显,岩浆侵入不仅破坏了煤层的原生结构、厚度、构造,还改变了煤质.本文依据刘店煤矿的勘探资料,对淮北矿业集团公司筹建矿井--刘店煤矿的岩浆侵入与煤质特征进行了探讨,以期为刘店煤矿的生产提供有益的帮助.     

基于GIS技术的河流污染动态模拟系统

本文论述了稳态均匀流场中的一维河流水质扩散模型,并在此模型的基础上,基于GIS二次开发技术开发了河流污染动态模拟系统。该系统以乐山市涌斯江支流段的地理底图及基本数据为例,实现了对河流污染情况的动态模拟。通过对该系统的一系列操作,可以对河段任意位置污染物浓度进行自动查询和修改,从而为河流水质污染的监测和管理提供可视化参考依据。     

多源遥感影像融合最佳波段选择及质量评价研究

本文选用了有蓝色波段和无蓝色波段两种遥感数据源,使用定量指标对各波段进行基本统计及分析,并计算各波段之间的联合熵、协方差、相关系数及最佳指数,确定四类遥感数据各自的最佳波段组合;并采用了几种融合方法将四种影像按照最佳波段组合融合,计算融合后影像与原始影像之间的相关系数,分析得到两类数据的最佳融合方法。