矿产资源研究所“三稀”矿产研究与找矿实践70年历程——回顾与启示   总被引：3，自引：1，他引：2  

杨岳清  王登红  孙艳  赵芝  刘善宝  王成辉  郭维明 《矿床地质》2021,40(4):655-692

稀有、稀土和稀散元素(三稀)目前已成为世界各国经济发展中的关键矿产.中华人民共和国成立以来,中国地质科学院矿产资源研究所作为中国矿床地质工作者大家庭中的成员,一直致力于三稀资源的研究和探索.一代又一代人,为国家做出了贡献.其中,对世界闻名的新疆可可托海3号脉和内蒙古白云鄂博稀有稀土矿床较早就投入了工作,他们为此付出了毕生精力;在湖南香花岭含铍条纹岩中发现了中国第一个新矿物——香花石;1970年后,在内蒙古巴尔哲、福建南平和四川大水沟稀土、稀有和分散元素等矿床发现后,也开展了深入系统的研究,特别是在中国首次发现风化壳离子吸附型稀土矿床后,对稀土元素赋存状态的确定和分布规律做出了重要贡献.进入21世纪,三稀资源被确定为关键矿产后,矿产资源研究所进一步加强了这方面的工作,不但取得了理论上的创新,而且发现了一批新的三稀矿产地,尤其是在川西甲基卡和可尔因等地投入了大量的地质、地球物理、地球化学、遥感、钻探等工作,其中钻探工作量就达11818.96 m,为把川西花岗伟晶岩型稀有金属矿集区建设成为国家大型锂矿基地作出了新贡献.对于卤水型锂及其他稀有金属矿产资源的调查研究和开发利用也一直是矿产资源研究所的重点,几十年来从未间断,在柴达木盆地西部、四川盆地东北部及江汉盆地等地近年来不断取得新进展.  相似文献   

刚果(金)绿纱铜钴矿床黑色页岩Rb-Sr测年及其区域成矿意义     

高帮飞  沈阳  钟长汀  马恒  张作伦 《地质学报》2021,95(4):1029-1049

中非铜钴矿带是全球最大最具经济价值的沉积型层状铜成矿带之一.区域内铜钴矿床形成分布主要受区域地层和构造控制,成矿具有多期特征.含矿地层中发育大量褶皱前浸染状和顺层脉状矿化,指示可能存在成岩之后和造山主构造变形之前的矿化叠加作用.本文通过绿纱铜钴矿床矿化黑色页岩全岩Rb-Sr测年及Sr-Nd同位素研究,获得早期浸染状矿化黑色页岩等时线年龄为742±32Ma(MSWD=0.39),与木瓦夏-恩古巴裂谷作用同期;晚期脉状矿化黑色页岩及与脉体中白云石、黄铜矿单矿物构成的内部等时线年龄分别为680±24Ma(MSWD=0.95)和678±21Ma(MSWD=1.5),为刚果克拉通与卡拉哈里克拉通俯冲造山作用初期.Sr,Nd同位素特征显示,早期浸染状矿化成矿物质来源长英质基底和同期基性火山岩;晚期脉状矿化成矿物质来源基性基底和赋矿围岩,与盆地内循环热卤水成矿有关.大量证据表明,顺层脉状矿化及其伴生切层脉状和角砾岩状矿化具有三维空间上的连通性,为同期矿化作用产物.脉体的形成与区域挤压作用引起的超高压流体水压致裂和侧向流动有关,区域挤压应力的动力来源于俯冲造山作用.700Ma左右,罗迪尼亚超大陆裂解结束及冈瓦纳超大陆聚合开始,引起区域构造体制从伸展向挤压转换,可能是区域大规模叠加成矿作用发生的地球动力学机制.  相似文献   

半参数模型在平面坐标转换中的应用     

赵富燕  孙李城  杨兆臣 《全球定位系统》2015,(3)

坐标转换在测绘领域一直起着至关重要的作用,而模型的选取又直接制约着转换的精度,通常在坐标转换中采用相似变换（Hermert）的方法,在平面坐标转换过程中一般采用4参数模型。然而当系统误差不可忽略时,该模型处理得到的结果并不理想。本文将半参数模型应用到平面坐标转换中,分别采用4参数模型和半参数模型两种方法对实验数据进行了处理,并进行了对比与分析。实验结果表明：在处理带有系统误差的平面坐标数据时,半参数模型比传统的参数模型更加精确。  相似文献   

《测绘法》适应性浅析     

阮于洲 《东北测绘》2012,(3):219-220

分析了新时期测绘发展面临的新形势,对《中华人民共和国测绘法》规定的有关概念内涵、管理体制、运行机制、准入制度等的适应性进行了探讨,对进一步修订《中华人民共和国测绘法》提出了建议。  相似文献   

Winter season stratospheric circulation in the SAMIL/LASG general circulation model   总被引：3，自引：0，他引：3  

任荣彩  吴国雄  宇婧婧 《大气科学进展》2009,26(3):451-464

In this paper, we examine the performance of the 26-level version of the SAMIL/LASG GCM (R42/L26) in simulating the seasonal cycle and perpetual winter mean stratospheric circulation as well as its variability by comparing them with the NCEP/NCAR reanalysis. The results show that the model is capable of reproducing many key features of the climatology and seasonal variation of the stratospheric circulation despite that the model’s mean polar vortex is stronger and more zonally symmetric compared to the obse...  相似文献   

Comparison of AnnAGNPS and SWAT model simulation results in USDA‐CEAP agricultural watersheds in south‐central Kansas     

Prem B. Parajuli  Nathan O. Nelson  Lyle D. Frees  Kyle R. Mankin 《水文研究》2009,23(5):748-763

This study was conducted under the USDA‐Conservation Effects Assessment Project (CEAP) in the Cheney Lake watershed in south‐central Kansas. The Cheney Lake watershed has been identified as ‘impaired waters’ under Section 303(d) of the Federal Clean Water Act for sediments and total phosphorus. The USDA‐CEAP seeks to quantify environmental benefits of conservation programmes on water quality by monitoring and modelling. Two of the most widely used USDA watershed‐scale models are Annualized AGricultural Non‐Point Source (AnnAGNPS) and Soil and Water Assessment Tool (SWAT). The objectives of this study were to compare hydrology, sediment, and total phosphorus simulation results from AnnAGNPS and SWAT in separate calibration and validation watersheds. Models were calibrated in Red Rock Creek watershed and validated in Goose Creek watershed, both sub‐watersheds of the Cheney Lake watershed. Forty‐five months (January 1997 to September 2000) of monthly measured flow and water quality data were used to evaluate the two models. Both models generally provided from fair to very good correlation and model efficiency for simulating surface runoff and sediment yield during calibration and validation (correlation coefficient; R², from 0·50 to 0·89, Nash Sutcliffe efficiency index, E, from 0·47 to 0·73, root mean square error, RMSE, from 0·25 to 0·45 m³ s^?1 for flow, from 158 to 312 Mg for sediment yield). Total phosphorus predictions from calibration and validation of SWAT indicated good correlation and model efficiency (R² from 0·60 to 0·70, E from 0·63 to 0·68) while total phosphorus predictions from validation of AnnAGNPS were from unsatisfactory to very good (R² from 0·60 to 0·77, E from ? 2·38 to 0·32). The root mean square error–observations standard deviation ratio (RSR) was estimated as excellent (from 0·08 to 0·25) for the all model simulated parameters during the calibration and validation study. The percentage bias (PBIAS) of the model simulated parameters varied from unsatisfactory to excellent (from 128 to 3). This study determined SWAT to be the most appropriate model for this watershed based on calibration and validation results. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

Air pollution hazard assessment using decision tree algorithms and bivariate probability cluster polar function: evaluating inter-correlation clusters of PM10 and other air pollutants     

Omar F. Althuwaynee  Wesam Al Madhoun 《地理信息系统科学与遥感》2020,57(2):207-226

ABSTRACT

The automated classification of ambient air pollutants is an important task in air pollution hazard assessment and life quality research. In the current study, machine learning (ML) algorithms are used to identify the inter-correlation between dominant air pollution index (API) for PM10 percentile values and other major air pollutants in order to detect the vital pollutants’ clusters in ambient monitoring data around the study area. Two air quality stations, CA0016 and CA0054, were selected for this research due to their strategic locations. Non-linear RPart and Tree model of Decision Tree (DT) algorithm within the R programming environment were adopted for classification analysis. The pollutants’ respective significance to PM10 occurrence was evaluated using Random forest (RF) of DT algorithms and K means polar cluster function identified and grouped similar features, and also detected vital clusters in ambient monitoring data around the industrial areas. Results show increase in the number of clusters did not significantly alter results. PM10 generally shows a reduction in trend, especially in SW direction and an overall minimal reduction in the pollutants’ concentration in all directions is observed (less than 1). Fluctuations were observed in the behaviors of CO and NO_x during the day while NOx displayed relative stability. Results also show that a direct and positive linear relationship exists between the PM10 (target pollutant) and CO, SO₂, which suggests that these pollutants originate from the same sources. A semi-linear relationship is observed between the PM10 and others (O₃ and NO_x) while humidity shows a negative linearity with PM10. We conclude that most of the major pollutants show a positive trend toward the industrial areas in both stations while tra?c emissions dominate this site (CA0016) for CO and NOx. Potential applications of nuggets of information derived from these results in reducing air pollution and ensuring sustainability within the city are also discussed. Results from this study are expected to provide valuable information to decision makers to implement viable strategies capable of mitigating air pollution effects.  相似文献   

前苏联铁路网的形成、发展和布局     

冯春萍 《世界地理研究》1994,(2)

前苏联是世界上铁路运输利用率最高的国家。本文从其铁路发展的背景条件出发，分析了铁路成为前苏联最主要运输方式的原因，并进一步探讨了前苏联铁路网的建设、发展和分布特点，对我国正在进行的大规模铁路建设有一定借鉴意义。  相似文献   

The Performance of Atmospheric Component Model R42L9 of GOALS／LASG   总被引：26，自引：0，他引：26  

WU Tongwen  LIU Ping  WANG Zaizhi  LIU Yimin  YU Rucong  WU Guoxiong 《大气科学进展》2003,20(5):726-742

This paper examines the performance of an atmospheric general circulation model (AGCM) developed at the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics (LASG/IAP). It is a spectral model truncated at R42(2.8125°long×1.66°lat) resolution and with nine vertical levels, and referred to as R42L9/LASG hereafter. It is also the new version of atmospheric component model R15L9 of the global ocean-atmosphere-land system (GOALS/LASG). A 40-year simulation in which the model is forced with the climatological monthly mean sea surface temperature is compared with the 40-year (1958-97) U.S. National Center for Environmental Prediction (NGEP) global reanalysis and the 22-year (1979-2000) Xie-Arkin monthly precipitation climatology. The mean DJF and JJA geographical distributions of precipitation, sea level pressure, 500-hPa geopotential height, 850-hPa and 200-hPa zonal wind, and other fields averaged for the last 30-year integrat  相似文献   

A hybrid method for the vulnerability assessment of R/C and URM buildings   总被引：6，自引：1，他引：6  

Andreas J. Kappos  Georgios Panagopoulos  Christos Panagiotopoulos  Gregorios Penelis 《Bulletin of Earthquake Engineering》2006,4(4):391-413

The methodology followed by the Aristotle University (AUTh) team for the vulnerability assessment of reinforced concrete (R/C) and unreinforced masonry (URM) structures is presented. The paper focuses on the derivation of vulnerability (fragility) curves in terms of peak ground acceleration (PGA), as well as spectral displacement (s _d), and also includes the estimation of capacity curves, for several R/C and URM building types. The vulnerability assessment methodology is based on the hybrid approach developed at AUTh, which combines statistical data with appropriately processed (utilising repair cost models) results from nonlinear dynamic or static analyses, that permit extrapolation of statistical data to PGA’s and/or spectral displacements for which no data are available. The statistical data used herein are from earthquake-damaged greek buildings. An extensive numerical study is carried out, wherein a large number of building types (representing most of the common typologies in S. Europe) are modelled and analysed. Vulnerability curves for several damage states are then derived using the aforementioned hybrid approach. These curves are subsequently used in combination with the mean spectrum of the Microzonation study of Thessaloniki as the basis for the derivation of new vulnerability curves involving spectral quantities. Pushover curves are derived for all building types, then reduced to standard capacity curves, and can easily be used together with the S _d fragility curves as an alternative for developing seismic risk scenarios.  相似文献