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1.
本文介绍了人为矿床的概念和研究概况,论述了人为矿床的分类、特征及开发利用的意义、优势、工作重点和难点。文章指出:人为矿床就是人类活动所产生的可以进行规模化利用而现在仍被视为“废弃物”的各种物质;人为矿床大多具有污染源和资源的双重属性,开发利用人为矿床是治理环境污染的釜底抽薪之法,开发利用人为矿床可以收到经济和环保的双重效益;人为矿床具有活动性和增生性,是真正“取之不尽用之不竭”的矿床,开发利用人为矿床,是发展循环经济的重要途径;人为矿床的分布与人类活动区域相关、赋存状态迥异于自然矿床、物质成分十分复杂;人为矿床具有可人为控制的特性;开发利用人为矿床,需要进行广泛的社会动员。 相似文献
2.
流体成矿系统与成矿作用研究 总被引：24，自引：4，他引：24
对几乎所有金属矿床类型来说，其形成过程均与金属从源岩的活化、原始渗滤、矿质运移和金属沉淀富集成矿关系密切，这些过程主要是由流体的运动和作用完成的。因此，识别金属和流体的来源，追溯流体从源区将金属运载至最终成矿部位所经过的路径，以及查明金属和流体沿运移通道发生的物理、化学和时间上的各种变化及其特殊性质，可以为矿床评价与勘查提供很有价值的定量成矿信息。成矿流体的来源－运移－沉淀（－堆积）过程会以流体成矿系统的形式保留下来。对流体成矿系统和作用的全面了解可通过调查活动的和古代的两种系统获得。活动流体成矿系统是目前正在进行原始矿质搬运的系统，调查这些系统可对运移通道中的含矿流体进行取样和监测研究。古流体成矿系统包括各时代从含金石英脉到铅－锌矿脉系统的所有热液脉型矿床以及沉积喷气型和所谓层控矿床。对含矿矿物和岩石的广泛岩石学、化学、流体包裹体和同位素研究将为定量评价与预测矿床的分布和变化提供至关重要的资料。流体成矿系统内具有一些重要特征，如各种地质要素的方向性、相关性和指示性变化。 相似文献
3.
两家人松散堆积体位于金沙江中虎跳峡左岸,为第四纪岩土体混杂堆积体,规模巨大,结构无序,透水性 强。文章通过野外调查和资料对比分析,揭示了该松散堆积体的发育特征和形成机制,认为两家人堆积体成因具 有复合性,是一种由滑坡、崩塌和崩坡积多期次形成的复合地质体,为典型的内外动力耦合作用的产物。最后对松 散堆积体的稳定性进行了初步评价,表明两家人堆积体整体式破坏可能性不大,局部性质脆弱,在地震、降雨和人 类工程活动作用下可能发生大面积的失稳破坏 相似文献
4.
Fluid inclusions in hydrothermal ore deposits 总被引：49，自引：0，他引：49
The principal aim of this paper is to consider some of the special problems involved in the study of fluid inclusions in ore deposits and review the methodologies and tools developed to address these issues. The general properties of fluid inclusions in hydrothermal ore-forming systems are considered and the interpretation of these data in terms of fluid evolution processes is discussed. A summary of fluid inclusion data from a variety of hydrothermal deposit types is presented to illustrate some of the methodologies described and to emphasise the important role which fluid inclusion investigations can play, both with respect to understanding deposit genesis and in mineral exploration. The paper concludes with a look to the future and addresses the question of where fluid inclusion studies of hydrothermal ore deposits may be heading in the new millenium. 相似文献
5.
Lisa‐Marie Shillito 《第四纪科学杂志》2011,26(6):576-588
Simultaneous thin section and phytolith observations of finely stratified anthropogenic deposits from the Neolithic settlement of Çatalhöyük, Turkey, dated between 7400 and 6000 BC provide evidence for both the depositional context and phytolith assemblage of these deposits. Although extracted phytoliths provide a general picture of vegetation that supports existing evidence of a local wet marshland environment, comparisons with observations of phytoliths in situ indicate a diverse range of microcontexts, as well as depositional and post‐depositional processes that influence phytolith size. This has implications for studies that use conjoined phytolith size as a proxy for water availability and early agricultural practices. Observations indicate a significant background noise of phytoliths and micro‐charcoal in the deposits, linked to the frequent use of fire, which has implications for interpreting assemblages where phytolith counts are low, such as from floors of buildings. This study confirms the usefulness of phytoliths in providing information on human plant use and environment where the taphonomy of the deposits is clear, and provides new evidence for wet farming of at least some of the wheat found at the site. It also suggests there needs to be greater consideration of phytolith taphonomy, which can be provided to an extent by combining phytolith analysis with thin section micromorphology. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
6.
WEI Dongyan DENG Xiaolin LIU Zhenmin YANG GengshengGeological Institute for Chemical Minerals Zhuozhou Hebei 《《地质学报》英文版》2000,74(3):613-617
A water/salt system in an evaporative environment is both a physicochemical region and a biological one. All the parameters of the system, such as the salinity, temperature and CO2 partial pressure, are affected by halo-philic bacteria. The system controls salt deposition but is modified by an accompanying ecological system; therefore it should be called a water/salt/biological system. Salt minerals result from accumulation of the remains of bacteria/algae, namely, bacteria/algae formation; whereas biological, biophysical and biochemical processes provide full evidence for organic involvement. Consequently, salt deposits should not be called purely chemical but biological/chemical ones. This new argument supplements and develops the traditional idea and helps perfect the mineralization theory of salts and even general deposits, thus giving guidance to prospecting for salt deposits. 相似文献
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This paper deals with the formation processes and the palaeoenvironmental significance of relict slope deposits located on the uppermost part of the north Portugal mountains. For this purpose, seven key sites representative of the different lithofacies have been selected and analysed in detail. The data show that three main dynamic processes are responsible for the emplacement of regional fossil slope deposits: runoff, debris flows and dry grain flows. The ubiquity of these processes and the lack of frost‐related features or landforms do not support the existence of severe Pleistocene climates in this part of the lberian Peninsula as postulated by previous work. Pedological data gathered at one of the study sites show that a subalpine environment was probably present at 700–800 m altitude between 29 and 14 kyr. Using data from the Pyrenees Mountains, a 6.5 to 12°C depression in mean annual temperature has been tentatively postulated for this Pleniglacial period. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Mineral Deposit Densities for Estimating Mineral Resources 总被引：1，自引：0，他引：1
Donald A. Singer 《Mathematical Geosciences》2008,40(1):33-46
Estimates of numbers of mineral deposits are fundamental to assessing undiscovered mineral resources. Just as frequencies
of grades and tonnages of well-explored deposits can be used to represent the grades and tonnages of undiscovered deposits,
the density of deposits (deposits/area) in well-explored control areas can serve to represent the number of deposits. Empirical
evidence presented here indicates that the processes affecting the number and quantity of resources in geological settings
are very general across many types of mineral deposits. For podiform chromite, porphyry copper, and volcanogenic massive sulfide
deposit types, the size of tract that geologically could contain the deposits is an excellent predictor of the total number
of deposits. The number of mineral deposits is also proportional to the type’s size. The total amount of mineralized rock
is also proportional to size of the permissive area and the median deposit type’s size. Regressions using these variables
provide a means to estimate the density of deposits and the total amount of mineralization. These powerful estimators are
based on analysis of ten different types of mineral deposits (Climax Mo, Cuban Mn, Cyprus massive sulfide, Franciscan Mn,
kuroko massive sulfide, low-sulfide quartz-Au vein, placer Au, podiform Cr, porphyry Cu, and W vein) from 108 permissive control
tracts around the world therefore generalizing across deposit types. Despite the diverse and complex geological settings of
deposit types studied here, the relationships observed indicate universal controls on the accumulation and preservation of
mineral resources that operate across all scales. The strength of the relationships (R
2=0.91 for density and 0.95 for mineralized rock) argues for their broad use. Deposit densities can now be used to provide
a guideline for expert judgment or used directly for estimating the number of most kinds of mineral deposits. 相似文献
9.
Contaminated ground and contaminated estuary sediment illustrated by two case histories 总被引：1，自引：0，他引：1
Contaminated ground forms a problem in all of the industrialized countries of the world. Contaminated ground may give rise
to hazards and that implies a degree of risk which also involves a problem of definition. The investigation of a site which
is suspected of being contaminated differs somewhat from a routine site investigation. Sampling of soil, groundwater and gas-producing
material may be required. Various precautions may be necessary to do this and personnel may have to wear protective clothing.
The first case history considered involves a site investigation for a relief sewer in Glasgow. As the site investigation progressed
it ran into made-ground which contained chemical waste. The presence of this waste meant that the nature of the investigation
changed and much more stringent safety precautions had to be taken. It also meant that the initial location of the sewer tunnel
had to be repositioned at greater depth in uncontaminated sandstone rather than in the superficial deposits above.
The other case history considers the contamination of sediments in the Forth Estuary. When trace metals are released into
the water column they can be transferred rapidly to the sediment phase by adsorption onto suspended particulate matter, followed
by sedimentation. Intertidal flats may be considered as important trace metal sinks since they accumulate large amounts of
suspended matter. Hence, in polluted estuaries the deposition of suspended particles on intertidal flats may thus cause severe
contamination. The Forth Estuary has unique contamination for British estuaries; it is experiencing significant Hg pollution.
In addition, due to the presence of a nuclear submarine base in the Forth Estuary, 60Co is detectable in the intertidal sediments. Temporal and spatial contamination patterns were analysed in relation to historical
and present pollution point sources. The effect of fluvial and marine sediment mixing on trace metals and other processes
controlling contaminant levels is reviewed. Preliminary results on quantifying sediment accretion rates using Caesium levels
are discussed.
Received: 9 August 1996 · Accepted: 17 December 1996 相似文献
10.
中国-俄罗斯原油管道工程(漠河-大庆段)冻土工程地质考察与研究进展 总被引：4，自引：2，他引：2
李国玉 金会军 盛煜 张建明 俞祁浩 齐吉琳 温智 吕兰芝 童长江 郭东信 王绍令 魏智 杨思忠 吉延俊 于少鹏 何瑞霞 常晓丽 郝加前 陈友昌 吴伟 翟镇远 赵意民 《冰川冻土》2008,30(1):170-175
在2005-2007年期间,先后3次对中国-俄罗斯原油管道漠河-大庆段沿线的冻土工程地质条件等进行科学考察,开展了冻土工程地质条件及其在气候变化和人类活动作用下的评价和预测研究.考察研究结果表明:管道沿线多年冻土在各类融区、季节冻土和水系等分隔作用下呈片状或岛状分布,沿线岛状、稀疏岛状及零星岛状占多年冻土区段的40%左右;管道沿线多年冻土随着气候的转暖和人类活动的影响不断退化.地形地貌单元、植被分布、地表水分条件的变化等局部因素对多年冻土的分布和地下冰的赋存产生重要的影响,管道沿线大约分布有50 km左右的沼泽湿地,其表层为腐殖质土及泥炭层,泥炭层下面分布着含土冰层或地下冰,是管道沿线最差的冻土工程地质地段;由于中俄原油管道沿线水系发育多,冻胀丘、冰椎和冰幔等不良冻土现象广泛分布.科学考察的成果为管道沿线冻土工程地质条件评价和预测、管道的稳定性影响分析以及后期的长期检测系统设置等研究奠定坚实的基础,进一步为即将开工的中俄原油管道漠河-大庆段工程的设计、施工提供科学依据. 相似文献
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12.
安徽铜陵矿集区是长江中下游成矿带内重要的多金属成矿区,该矿集区具有大规模的成矿作用和多种类型的复杂成矿系统演化,找矿潜力大,研究程度较高。区内广泛发育一系列层状硫化物矿床,其成因问题一直是中国矿床学界争议的焦点之一。文章从成矿年代学、成矿流体来源以及成矿物质来源等方面,对近半个世纪以来国内外学者对该矿集区内层控硫化物矿床成因研究的主要成果进行了初步归纳,并对对铜陵矿集区的成矿规律和成矿机制取得了一些新的认识:①铜陵矿集区的层状硫化物矿床的成矿过程包含海西期海底喷流沉积和燕山期岩浆热液叠加富集两个阶段,但是对于不同矿床的贡献是有差异的,具体到单个矿床需要结合多种方法进行详细分析;②燕山期岩浆热液交代改造、叠加富集成矿作用发生在早白垩世,大约持续20 Ma,峰值在140 Ma左右;③燕山期含矿岩浆从早到晚岩石地球化学上表现出由中基性→中酸性→中性的演化趋势,以岩浆活动高峰期(140 Ma±)的花岗闪长岩成矿规模最大,这种成矿偏好性是否与深部岩浆源区性质有关值得深入研究;④目前关于海西期喷流沉积作用对成矿的贡献的工作很少,期望对其有正确客观的评价。 相似文献
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A combined study of radar facies,lithofacies and three‐dimensional architecture of an alpine alluvial fan (Illgraben fan,Switzerland) 
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下载免费PDF全文 Alluvial fans serve as useful archives that record the history of depositional and erosional processes in mountainous regions and thus can reveal the environmental controls that influenced their development. Economically, they play an important role as groundwater reservoirs as well as host rocks for hydrocarbons in deeply buried systems. The interpretation of these archives and the evaluation of their reservoir architecture, however, are problematic because marked heterogeneity in the distribution of sedimentary facies makes correlation difficult. This problem is compounded because the accumulated sedimentary deposits of modern unconsolidated fan systems tend to be poorly exposed and few such systems have been the focus of investigation using high‐resolution subsurface analytical techniques. To overcome this limitation of standard outcrop–analogue studies, a geophysical survey of an alpine alluvial fan was performed using ground‐penetrating radar to devise a scaled three‐dimensional subsurface model. Radar facies were classified and calibrated to lithofacies within a fan system that provided outcropping walls and these were used to derive a three‐dimensional model of the sedimentary architecture and identify evolutionary fan stages. The Illgraben fan in the Swiss Alps was selected as a case study and a network of ca 60 km sections of ground‐penetrating radar was surveyed. Seven radar facies types could be distinguished, which were grouped into debris‐flow deposits and stream‐flow deposits. Assemblages of these radar facies types show three depositional units, which are separated by continuous, fan‐wide reflectors; they were interpreted as palaeo‐surfaces corresponding to episodes of sediment starvation that affected the entire fan. An overall upward decline in the proportion of debris‐flow deposits from ca 50% to 15% and a corresponding increase in stream‐flow deposits were identified. The uppermost depositional unit is bounded at its base by a significant incision surface up to 700 m wide, which was subsequently filled up mostly by stream‐flow deposits. The pronounced palaeo‐surfaces and depositional trends suggest that allocyclic controls governed the evolution of the Illgraben fan, making this fan a valuable archive from which to reconstruct past sediment fluxes and environmental change in the Alps. The results of the integrated outcrop–geophysical approach encourage similar future studies on fans to retrieve their depositional history as well as their potential reservoir properties. 相似文献
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深水异地沉积研究在我国已有30年历程,它经历了70年代浊流沉积研究探索阶段、80年代重力流沉积研究蓬勃发展阶段和90年代深水牵引流沉积研究阶段。70年代浊流沉积研究刚刚起步,以资料积累和深化认识为主,成果欠丰;深水牵引流沉积研究则仅有少量探索。80年代深水重力流沉积研究已从单一类型延伸到多种类型,从陆源碎屑重力流沉积扩展到碳酸盐和火山碎屑重力流沉积,从海洋发展到湖泊,从一般性描述转入沉积模式、控制因素及含矿性的探讨,出现了突飞猛进、硕果累累的可喜局面;而深水牵引流沉积研究也有了实质性进展。90年代重力流沉积研究继续保持稳步发展态势,而深水牵引流沉积研究有了更大的进展,取得了令世人注目的重要成果。展望未来,深水异地沉积研究任重而道远,相信我国沉积学学者在这一领域研究必将迎来前所未有的盛世。 相似文献
15.
大型复杂松散堆积体形成机制的内外动力耦合作用初 探 总被引：5，自引：2，他引：3
在我国西部山区广泛发育和分布第四纪大型复杂松散堆积体,这是一套介于土、岩之间的过渡类型的地质体;其成因复杂,主要包括残坡积物、崩滑堆积体、冲洪积物、冰碛物和冰水沉积物等两种或多种组合混杂堆积,明显区别于东部平原区的单一成因类型。本文通过资料对比分析,对大型复杂松散堆积体的一般特征、主要类型和区域分布规律进行了系统总结,最后从耦合的角度来探讨其成因机制,并提出河谷型松散堆积体的内外动力耦合概念模型,研究认为大型复杂松散堆积体属于典型的内外动力耦合作用产生的多期次、成因复杂的复合地质体。 相似文献
16.
LI Shixin ZHANG Tingshan ZHANG Xi LIANG Zeliang JI Dongsheng Mihai Emilian POPA YONG Jinjie LUO Jinyu ZENG Jianli ZHU Haihua 《《地质学报》英文版》2023,97(5):1422-1450
Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years. This study discusses the co-evolution of volcanism and deep-water gravity flow deposits at the southern margin of the Junggar Basin, based on petrology, geochronology and geochemical analyses. The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism, resulting in the formation of slumping gravity flows. The occurrence... 相似文献
17.
以大量国内外脉状金矿成矿流体研究资料为基础，本文介绍并综合评述了成矿流体成分、性质和来源三方面的研究现状与进展，指出全球性脉状金矿成矿流体成分惊人的一致性可能会对脉状金矿成矿流体来源和成矿机制的认识产生深刻的影响，把相同构造背景下一组脉状金矿床作为一个统一的群体去研究它们的形成、演化可能是脉状金矿成因研究的一个趋势。 相似文献
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Traces of historical tropical cyclones and tsunamis in the Ashburton Delta (north‐west Australia) 下载免费PDF全文
下载免费PDF全文 Simon Matthias May Dominik Brill Max Engel Anja Scheffers Anna Pint Stephan Opitz Volker Wennrich Peter Squire Dieter Kelletat Helmut Brückner 《Sedimentology》2015,62(6):1546-1572
Although the north‐western coast of Western Australia is highly vulnerable to tropical cyclones and tsunamis, little is known about the geological imprint of historic and prehistoric extreme wave events in this particular area. Despite a number of site‐specific difficulties such as post‐depositional changes and the preservation potential of event deposits, both tropical cyclones and tsunamis may be inferred from the geomorphology and the stratigraphy of beach ridge sequences, washover fans and coastal lagoons or marshes. A further challenge is the differentiation between tsunami and storm deposits in the geological record, particularly where modern deposits and/or historical reports on the event are not available. This study presents a high‐resolution sedimentary record of washover events from the Ashburton River delta (Western Australia) spanning approximately the last 150 years. A detailed characterization of event deposits is provided, and a robust chronostratigraphy for the investigated washover sequence is established based on multi‐proxy sediment analyses and optically stimulated luminescence dating. Combining sedimentological, geochemical and high‐resolution optically stimulated luminescence data, event layers are assigned to known historical events and tropical cyclone deposits are separated from tsunami deposits. For the first time, the 1883 Krakatoa and 1977 Sumba tsunamis are inferred from sedimentary records of the north‐western part of Western Australia. It is demonstrated that optically stimulated luminescence applied in coastal sedimentary archives with favourable luminescence characteristics can provide accurate chronostratigraphies even on a decadal timescale. The results contribute to the data pool of tropical cyclone and tsunami deposits in Holocene stratigraphies; however, they also demonstrate how short‐lived sediment archives may be in dynamic sedimentary environments. 相似文献
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环太平洋成矿带斑岩-矽卡岩型铜矿和与花岗岩有关的锡多金属矿研究现状与展望 总被引：8，自引：6，他引：2
长期以来,斑岩型铜矿是研究和勘查的热点。在20世纪70~90年代,对与花岗岩有关锡矿进行了大量深入研究,近几年,锡被列为一种关键金属,锡矿的研究和勘查又成为新的热点之一。锡矿和铜矿是环太平洋地区乃至全球最重要的两种矿床,但两者的成矿物质和成矿过程相差迥异。环太平洋地区的锡矿和铜矿主要形成于晚中生代至新生代,通常认为与太平洋板块俯冲有关,包括古太平洋板块、伊泽奈岐板块、法拉龙板块以及现今太平洋板块。本文主要综述了环太平洋成矿域的斑岩-矽卡岩铜矿和与花岗岩有关锡矿的时空分布特点、成矿岩体、矿床成因以及成矿环境的研究现状。尽管,目前已经取得了诸多重要进展,但仍然存在一些重要的科学问题亟待解决,例如,1)中国东部平行同时代成对出现的三条锡(钨)成矿带与斑岩铜矿成矿带的形成机制? 2)沿欧亚大陆边缘发育长达一万多公里的巨型铜金锡成矿带,而且绝大多数矿产发育于一系列伸展盆地中,其成矿背景是什么?此外,我们认为开展玻利维亚和大兴安岭南段Sn-Ag成矿系统的对比研究,是推动大兴安岭南段及邻区锡矿找矿取得突破的重要途径。 相似文献