Dating of mine waste in lacustrine sediments using cesium-137

For over a century Medicine Lake in northern Idaho has received heavy-metal-laden tailings from the Coeur d'Alene mining district. Establishing the depositional chronology of the lake bottom sediments provides information on the source and rate of deposition of the tailings. Cesium-137, an isotope produced in the atmosphere by nuclear bomb tests, was virtually absent in the environment prior to 1951, but reached its apex in 1964. Our analysis of cesium-137 in the sediments of Medicine Lake revealed that 14 cm of fine-grained tailings were deposited in the lake from 1951 to 1964 and tailing deposition downstream was greatly reduced by the installation of tailings dams in the district in 1968. Cesium-137 analysis is accomplished by a fairly simple gamma-ray counting technique and should be a valuable tool for analyzing sedimentation in any lacustrine environment that was active during the 1950s and 1960s.     

三山岛金矿F3断裂带的水文地质工程地质特征及灾害防治

本文对三山岛金矿F3断裂带的构造、岩性和水动力学特征进行了研究,对矿坑开挖中的突水和坑道碎屑流的成因做了探讨,并在水文地质结构、水化学、水同位素及水文地热学的综合研究基础上,对未来的二期井下工程开挖中可能出现的工程地质问题进行了预测,提出了防治方案。     

矿山地震研究述评

就采矿引起的诱发地震活动,即矿山地震的国际研究动态进行评述.重点介绍矿山地震的命名、早期观测与研究、几个主要矿震国家的情况、矿震的分类、矿震的震源机制、矿震震源参数与定标率等问题.还就利用矿山作为天然地震的预报实验场和作为地震技术的推广市场问题进行探讨.     

Fractionation of phosphorus in the sediments of a tropical estuary

Fractionation of phosphorus in the sediments of the Cochin estuary situated along the southwest coast of India was studied by applying sequential chemical extraction. The different forms of phosphorus were estimated seasonally (premonsoon, monsoon, and postmonsoon) under eight different schemes. The major forms of phosphorus analyzed were exchangeable P, anion exchangeable P, carbonate-bound P, labile and resistant organic P, Fe and Al P, calcium-bound P, and hydrolyzable surplus P. Quantitatively, the above fractions in isolation or in combination vary in content due to chemoestuarine variability and seasonal fluctuations. Changes in speciation have been noted in association with salinity variations in the waterway, especially following enhanced river runoff during the monsoon. The chemical forms of the sediment-bound phosphorus in the northern parts of this estuary have been shown to be modified by nonpoint sources. Sediment P fractionation defines the role of chemical speciation of phosphates (as nutrients) and is indicative of the processes controlling the pathways of P into the coastal waters. The changes in the exchangeable P, together with marked regional variations in calcium-bound P, exemplify the complex estuarine variability of phosphorus. Enhanced amounts of exchangeable P mark its appearence in high saline waters, signifying the presence of biologically available nutrient phosphorus. The calcium-bound P and hydrolyzable surplus P show significant relation with sediment organic carbon and Fe whereas other forms do not exhibit any marked covariation. The Ca and Na NTA extraction scheme is very specific in its selectivity.     

Mine ventilation planning in the 1980s

Conclusions In this paper, the author has attempted to trace the development of mine ventilation planning from the traditional, manual and largely empirical methods of the past to the numerate computer-based techniques of the 1980s.The computer revolution has changed the face of many engineering disciplines, not least mine environmental engineering. Nevertheless, the mining industries of the world have not all been equally progressive in adapting to the flexibility, power and practical utilization of the new methodologies. It is, for example, incongruous that current textbooks on mine ventilation separate completely the topics of network analysis and ventilation planning with very little cross-referencing. Many of the current generation of mine ventilation engineers recognize the need to know about computers but find difficulty in translating this into their daily work. The growing availability of self-teaching, friendly software for personal microcomputers, coupled with interactive graphics, will assist greatly in promoting uncomplicated but powerful usage of computers.Young engineers now graduating from universities and colleges have been brought up in a computer-oriented environment and are competent in interacting with these machines. Indeed, they wonder how the job was ever done without magnetic data bases and high-speed computation aid.     

基于MatLab的神经网络在江苏矿山地质环境评估中的应用

神经网络作为一种新的方法体系,具有分布并行处理、非线性映射、自适应学习和鲁棒容错等特性,在模式识别、控制优化和智能信息处理等方面有着广泛的应用。利用MatLab的神经网络工具箱,建立了江苏矿山地质环境质量的评估模型,评估结果经过实际验证,具有较高的可信度和实用性。     

Arsenic in mine waters: an international study

 Hydrochemical data are presented for arsenic (As) in the mine waters of 34 gold and base-metal mining localities in seven countries of south-east Asia, Africa and Latin America, encompassing contrasting climatic settings and at least eight discrete styles of primary mineralization. Peak dissolved As concentrations at these sites range from 0.005–72 mg/l, with the United States Environmental Protection Agency (US-EPA) potable water threshold of 50 μg/l exceeded in 25 cases. Arsenate (As⁵⁺) constitutes the dominant species at over 80% of sites. Very high dissolved As concentrations (>1 mg/l) show no systematic between-site relationship with mine water pH/Eh regime. Important determinants of mine water As fluxes include iron hydrochemistry, the presence of cyanic ore processing effluents, site geology, the paragenetic sequence that follows sulphide oxidation, climate and mine management. Human toxicological impacts of As contamination have been recognized at only one case-study site, with a further four considered to warrant more detailed risk assessment. Received: 2 November 1999 · Accepted: 21 March 2000     

矿震预报可能性的探讨

矿震是危害矿山安全生产的严重灾害,人们在长期生产实践和研究探索中发现,应用断裂力学知识和地震科学知识以及矿山形变测量资料,有可能对矿山地震作出某种预报。     

浅论砚石台煤矿滑覆构造及煤炭资源远景

对砚石台地区地层构造及滑覆构造组成要素、特征、形成机制进行了系统分析，论述了滑覆构造对煤层的影响，预测了－５００ｍ标高以下构造形态，提出－５００ｍ标高以下无须工作的建议。     

对中梁山煤矿地质构造特征的认识

根据３０多年矿井生产实测资料，对中梁山煤矿地质构造进行了分析研究，认为该矿地质构造虽然复杂，但也具有一定的规律，可分为简单、中等、复杂等不同构造区，大断层虽较多但对矿井开采影响不大，只是小型压扭性断层对采矿造成一定困难，故提出开采时应对症下药及保护资源的建议。