基于模糊综合评判的高原盆地城市水源地脆弱性评价

根据高原盆地城市水源地脆弱性内涵, 评价指标可量化性及不同水源地之间可比性, 选取了水源地水文气象、生态环境、水源污染和地表扰动状况4个方面14个指标, 构建了高原盆地城市水源地脆弱性指标体系.基于高原盆地城市水源地复杂性和指标评价标准界线的模糊性, 采用层次分析法确定指标权重, 应用模糊综合评判法建立评价模型, 运用所建立的评价模型对昆明市松华坝水源地脆弱性进行了评价.结果表明, 昆明市松华坝水源地为中度脆弱. 其中, 水文气象因子、水源污染因子处于中度脆弱状态, 生态环境因子处于轻度脆弱状态, 地表扰动因子介于轻度脆弱与中度脆弱状态之间.     

Source of lead in the gold-bearing quartz-fuchsite vein at the Dome mine,Timmins area,Ontario, Canada

The quartz-fuchsite vein at the Dome mine, Timmins area, Canada, is characterized by a consistent spatial association of gold and galena. A lead isotope study was carried out to trace the source of the lead in the galenas, and to evaluate possible source reservoirs for the gold. Although other sources cannot be entirely ruled out, the lead isotope composition of most of the galenas and of local quartz-feldspar porphyries suggests that most of the lead in the vein-galenas was derived from the Dome mine porphyries. However, lead isotope systematics do not allow unique constraints to be placed on the gold source. Conceptual genetic models commonly advocate gold source reservoirs such as shallow to deep seated igneous intrusions, the middle to lower crust or the mantle for Archean lode gold deposits. A likely scenario is that ore-bearing hydrothermal fluids originated at depth, and were preferentially channeled along the porphyries to the site of ore deposition. The hydrothermal fluids leached lead from the porphyries, and deposited gold and galena together in the quartz-fuchsite vein. Two galena samples have anomalous lead compositions and are colinear with the main galena cluster suggesting one or more contamination episodes, broadly between 1250 and 2480 Ma, resulting in further addition of radiogenic lead to the galenas.     

Social vulnerability indices: a comparative assessment using uncertainty and sensitivity analysis

Social vulnerability indices have emerged over the past decade as quantitative measures of the social dimensions of natural hazards vulnerability. But how reliable are the index rankings? Validation of indices with external reference data has posed a persistent challenge in large part because social vulnerability is multidimensional and not directly observable. This article applies global sensitivity analyses to internally validate the methods used in the most common social vulnerability index designs: deductive, hierarchical, and inductive. Uncertainty analysis is performed to assess the robustness of index ranks when reasonable alternative index configurations are modeled. The hierarchical design was found to be the most accurate, while the inductive model was the most precise. Sensitivity analysis is employed to understand which decisions in the vulnerability index construction process have the greatest influence on the stability of output rankings. The deductive index ranks are found to be the most sensitive to the choice of transformation method, hierarchical models to the selection of weighting scheme, and inductive indices to the indicator set and scale of analysis. Specific recommendations for each stage of index construction are provided so that the next generation of social vulnerability indices can be developed with a greater degree of transparency, robustness, and reliability.     

Environmental impact assessment of open pit mining in Iran

Mining is widely regarded as having adverse effects on environment of both magnitude and diversity. Some of these effects include erosion, formation of sinkhole, biodiversity loss and contamination of groundwater by chemical from the mining process in general and open-pit mining in particular. As such, a repeatable process to evaluate these effects primarily aims to diminish them. This paper applies Folchi method to evaluate the impact of open-pit mining in four Iranian mines that lacked previous geo-environmental assessment. Having key geologic resources, these mines are: Mouteh gold mine, Gol-e-Gohar and Chogart iron mines, and Sarcheshmeh copper mine. The environmental components can be defined as public health and safety, social relationships, air and water quality, flora and fauna hence, various impacting factors from the mining activities were estimated for each environmental component. For this purpose, each impacting factor was first given a magnitude, based solely on the range of possible scenarios. Thereafter, a matrix of weighted factors was derived to systematically quantify and normalize the effects of each impacting factor. The overall impact upon each individual environmental component was then calculated by summing the weighted rates. Here, Folchi method was applied to evaluate those environmental conditions. Based on the acquired results, the present paper finally concludes that amongst four case histories in Iran, Sarcheshmeh copper mine significantly affects the environment, with critical level of air pollution there.     

冀西石湖金矿床地质地球化学特征

文章根据冀西石湖金矿床的矿区地质特征、矿石的微量元素地球化学特征、稀土元素的地球化学特征、稳定同位素地球化学特征等的研究,认为金矿赋矿层位为阜平群团泊口组。硫、铅同位素分析显示硫、铅来源于地幔,研究表明石湖金矿床成矿物质主要来源于矿源层。     

湖南省农业生态水资源库脆弱性评价

以湖南农业生态水资源库为研究对象,分析了其脆弱性成因和主要表现.从脆弱性成因角度构建了包含10个具体指标的湖南生态水资源库脆弱性评价指标体系,运用模糊物元评价模型对85个县级评价单元的农业生态水资源库脆弱度进行综合评判.结果表明:全省农业生态水资源库脆弱性等级以中等脆弱为主,其中,微脆弱等级11个,占总评价单元的12.9%;中等脆弱等级74个,占总评价单元的87.1%.脆弱度空间分布存在"西部大于东部,南部大于北部"的总体分布态势.其中,以湘西北、湘西南和湘南所构成的外部环形地带和以长沙、衡邵盆地为中心的中东部地带为全省两个比较明显的高脆弱区(带).     

Assessing the inconsistency between groundwater vulnerability and groundwater quality: the case of Chapala Marsh, Mexico

Aquifer systems present intrinsic properties such as vulnerability, which is identified as the potential risk of groundwater pollution by contaminants generated by human activity. When there are surface sources of pollution, usually there is a direct relationship between high vulnerability and decreased water quality. Nevertheless, this relationship is not observed in all aquifers and so the causative circumstances of inconsistencies between aquifer vulnerability and water quality have been investigated. This work addresses the vulnerability assessment of the Chapala Marsh area, Mexico, using SINTACS analysis. The Chapala Marsh aquifer is characterized by a granular structure and a fractured recharge zone; there are natural and anthropogenic sources of pollution. The results show discrepancies between the vulnerability indices and groundwater quality, as indicated by the existence of vulnerable areas with good water quality and vice versa. This is because the SINTACS method works well when contaminants have only vertical movement. For scenarios with lateral movement of contaminants, the method of geographic weighted regression (GWR) is used to model the influence of potential sources of contaminants on the water quality.     

甘肃省合作市德乌鲁岩体及外围金多金属成矿区成矿地质特征

德乌鲁岩体及外围金多金属成矿区位于中秦岭海西褶皱带西段。区内矿产主要有金、锑、铜、铅、锌;矿化类型主要有蚀变岩型金(锑)矿化类型和矽卡岩型的铜砷、铜铅锌多金属矿化类型。各矿点在空间分布上,显示等间距分布的基本特征,受近南北向分布的断层蚀变破碎带控制。矿化蚀变主要有黄铁矿化、电气石化、硅化、绢云母化、毒砂化、辉锑矿化、次生蚀变以褐铁矿化、高岭土化。本文结合德乌鲁岩体及外围区域成矿特点、矿床分布规律、成矿地质特征、控矿因素,从本区的大地构造背景及区域构造活动特点等两个方面对区内成矿构造破碎蚀变带的形成进行了力学成因研究,并提出了本区今后找矿的主要方向。     

冀西石湖金矿床地质地球化学特征研究

通过冀西石湖金矿床的矿区地质特征、矿石的微量元素地球化学特征、稀土元素的地球化学特征、稳定同位素地球化学特征等研究,认为石湖金矿的赋矿层位为阜平群团泊口组,硫、铅来源于地幔,金矿床成矿物质主要来源于矿源层.     

成都市近地表大气尘铅分布特征及源解析

分析了成都市近地表大气尘样品铅及其同位素含量比的测定数据,铅含量变化范围为(119.76～1327.42)×10^-6,均值为374.51×10^-6,统计标准偏差为273.36,变异系数为0.73,说明成都市近地表大气尘铅含量变化大。燃煤飞灰的放射性成因铅明显高于汽油和柴油,可作为鉴别大气尘铅来源的证据。铅同位素含量数据表明成都市近地表大气尘的铅污染是复合污染源所致,其中,相对清洁区污染以建筑扬尘为主,中度污染区是汽车尾气和扬尘的叠加作用,重污染区是燃煤飞灰汽车尾气和工业污染源的综合表征。     

空气反循环钻探在紫金山金铜矿生产勘探中的应用

金山金铜矿经过几十年的大规模生产,金矿开采已进入矿体的边部和底部,矿体规模小,形态、产状复杂,矿石性质变化大,保有资源储量仅能满足矿山未来几年的生产需要,急需勘探接替资源。结合矿山生产实际和矿区地质条件,选择空气反循环钻探作为主要探矿手段。在分析空气反循环钻探工艺原理和适用条件的基础上,对施工机具的选取进行了详细阐述。通过对比,分析空气反循环钻探在紫金山金铜矿露采生产勘探、北口排土场含金废石（人工堆渣“矿床”）勘查中的成效以及问题。实践证明,空气反循环钻探技术可以用于紫金山金铜矿的生产勘探。     

地下水污染风险源识别与分级方法

由于目前缺乏一套完整成熟的地下水污染风险源准确识别与分级方法, 在综合解析污染源结构、污染物输移过程评价的基础上, 构建了涵盖地下水易污性和地下水污染源两部分多因素耦合的风险源识别模型, 其中从污染源特性和污染物性质两方面建立了污染源危害性评价参数体系.以地下水易污性指数和污染源潜在危害性评价指数作为风险源分级指标, 采用乘积模型进行了风险源的评价与分级.选择某水源地对所建方法进行实例分析, 确定了地下水污染的高风险源区.结果表明, 污染源和地下水易污性共同决定了地下水污染的风险源, 所建方法对地下水污染的预防及污染源的有效监管有重要意义.      

浙江省诸暨至龙泉一带金矿床的铅同位素地球化学研究

本文研究了浙江省诸暨至龙泉一带金矿床的铅同位素地球化学特征。通过研究铅同位素组成、源区特征值和模式年龄,对该区金矿床得出以下两点认识:1.该区金矿床铅同位素组成在区域上具有一定的变化趋势,并可分为二大类,即正常铅和弱放射性成因异常铅,它们反映了一定的物源特征;2.该区金矿床的区域成矿时代为400—700Ma,结合区域成矿地质特征,可以证明该区金矿床主要为变质热液矿床。     

Heat risk assessment based on mobile phone data: case study of Bratislava,Slovakia

The aim of this interdisciplinary study is to assess the heat risk for Bratislava. The following layers were created to compute the risk index: the hazard layer of air temperature, a mitigation layer of tree vegetation, an exposure layer of population and a vulnerability layer of individuals over 65 years of age. The MUKLIMO_3 model was used to evaluate the field of mean surface air temperature at 9 PM during selected days of the summer heat wave in August 2018. The tree vegetation layer, in the form of percentage per grid cell, was derived from Sentinel-2 satellite data. Population density data are based on mobile positioning data, and elderly population data are based on a gridded database from the statistical census. Input layers were unified into a resolution of 500 × 500 m, and the heat risk index was calculated by summation of the weighted input layers. The results reflect the variability of the population and the elderly population within the city, as well as the variability of the temperature field, which is caused by the joint effect of an urban heat island and topography. The highest values of risk index occur within the broader city centre, with specific hot spots at several places.

     

Geochemical characteristics of mineral air particles emitted inside a clay atomisation plant which introduces waste recycling processes

The objective of this work is to assess the concentrations of three factions of air particles (settable particles, TSP and PM10) and the levels of several toxic elements in a clay atomisation industry through aerosol sampling at several points inside an industrial plant. Mechanical activities, which produce diffuse emissions, are the main process of discharge of particles in both indoor and outdoor workplace environments in the atomisation plant. The levels of As, Cd, Pb, Zn, Ba and Ni increase in the zones with higher concentrations of particles and lower ventilation. The concentrations of As and F are not influenced by the recycling processes. The levels of Cd and Pb do not show great enrichment in air particles collected inside the atomisation plant although the content of both elements is associated with ceramic muck recycling. Finally, the content of B in waste water is mainly transferred in gaseous phase to the atmosphere during the process of drying by atomisation.     

Assessment of the impact of biogenic VOC emissions in a high ozone episode via integrated remote sensing and the CMAQ model

In many metropolitan regions, natural sources contribute a substantial fraction of volatile organic compound (VOC) emissions. These biogenic VOC emissions are precursors to tropospheric Ozone (O₃) formation. Because forests make up 59% of the land area in Taiwan Province, China, the biogenic VOC emissions from forests and farmland could play an important role in photochemical reactions. On the other hand, anthropogenic emissions might also be one of the major inputs for ground level O₃ concentrations. Hence, emission inventory data, grouped as point, area, mobile and biogenic VOC sources, are a composite of reported and estimated pollutant emission information and are used by many air quality models to simulate ground level O₃ concentrations. Before using relevant air quality models, the emission inventory data generally require huge amounts of processing for spatial, temporal, and species congruence with respect to the associated air quality modeling work. The fist part of this research applied satellite remote sensing and geographic information system (GIS) analyses to characterize land use/land cover (LULC) patterns, integrating various sources of anthropogenic emissions and biogenic emissions associated with a variety of plant species. To investigate the significance of biogenic VOC emissions on ozone formation, meteorological and air quality modeling were then employed to generate hourly ozone estimates for a case study of a high ozone episode in southern Taiwan, which is the leading industrial hub on the island. To enhance the modeling accuracy, a unique software module, SMOKE, was set up for emission processing to prepare emission inputs for the U.S. EPA’s Models-3/CMAQ. An emission inventory of Taiwan, TEDS 4.2, was used as the anthropogenic emission inventory. Biogenic emission modeling was accomplished by BEIS-2 in SMOKE, with improvement of local LULC data and revised emission factors. Research findings show that the majority of biogenic VOC emissions occur in the mountainous areas and farmlands. However, the modeling outputs show that downwind of the most heavily populated and industrialized areas, these biogenic VOC emissions have less impact on air quality than do anthropogenic emissions.     

冀西北黄土梁金矿控矿因素分析

河北省赤城县黄土梁金矿产于水泉沟-大南山碱性杂岩体内接触带,矿床受钾化正长岩及断裂构造双重控制.矿床具矿化带宽、规模大、贫硫化物、蚀变单一、矿石类型简单、埋藏浅、易采选等特点,是一处与海西期-燕山早期岩浆活动有关的热液矿床.     

六盘水市煤炭资源开发环境影响初探

探讨了六盘水市煤岩资源开发过程中产生的废弃物,煤矸石、矿区废水、废气对其环境的危害性,指出其环境治理的紧迫性,应加强综合治理。     

西安市地下水污染广义/狭义脆弱性对比研究

从"污染源排放→包气带输送→地下水污染"的系统出发,提出了地下水污染广义和狭义脆弱性的概念,并构建了相应的指标体系和评价方法;在广泛污染源调查和水文地质调查的基础上,在GIS支持下完成了地下水污染脆弱性分析试验.结果显示:纯水文地质条件的狭义脆弱性,各河道、漫滩阶地、一级阶地和老城人工填土区最为脆弱;考虑土地利用和污染源分布的广义脆弱性评价,西安市建城区和北郊污灌区敏感最高.从而得出,狭义脆弱性适合人类活动差异较小的较大区域,而广义脆弱性适合人类活动差异较大的城市区域,两者有其适用的条件和范围.     

加快黄金发展步伐的几点思考

本文详细分析了黄金矿产地质勘查、矿山建设及金矿生产等阶段工作的特点及其相互关系,探索性地提出提前建矿,缩短探矿和建设周期的办矿方式,并就如何加快黄金发展步伐问题提出了几点思考。