Cratonic lithospheric mantle is composed of predominantly refractory materials that formed at higher mantle potential temperatures ( T P) than recorded in non-cratonic peridotites. It also shows stronger depletion and fractionation of Pd and Pt from Ru, Os and Ir than oceanic, supra-subduction zone or off-cratonic lithospheric mantle, as well as some of the lowest Se and Te contents. The varied response of the highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au), and their embedded radioactive decay systems, to changes in oxygen fugacity ( f O2), sulfur fugacity ( f S2) and pressure ( P )—in particular through the impact of these parameters on the stability of the main HSE-bearing sulfide and alloy phases makes them potentially powerful tracers of their melting environment. Therefore, investigation of the HSE systematics of cratonic mantle peridotites, in combination with information from Re–Os isotopes on time-integrated enrichment or depletion, can help us to understand processes leading to mantle differentiation and continental lithosphere formation in the Archean, which are controversial subjects despite decades of research. The longevity of the cratonic lithosphere implies that there was ample opportunity for secondary overprint, obscuring our view of earlier processes. For example, destabilization of platinum-group element (PGE: Os, Ir, Ru, Rh, Pt, Pd) alloy leading to depletions in the compatible PGE, and perhaps Pt, in some cratonic mantle samples may occur in an oxidizing mantle wedge or through interaction with oxidizing small-volume, volatile-rich melts that typically invade cratonic roots. Such melts may eventually deposit S, Pd, Pt and Re and also capture remaining PGE alloys, consistent with the anomalous S-rich character of many kimberlite-borne xenoliths. Their basalt-borne counterparts show additional late effects of subaerial degassing that can deplete volatile elements (S, Re, Os). Basaltic melts can also scavenge PGE alloys at depth, while still sulfide-undersaturated. Such melts, may, …
克拉通岩石圈地幔主要由耐火物质组成，形成于比非克拉通橄榄岩记录的更高的地幔位温(T P)。Pd和Pt在Ru、Os和Ir中的损耗和分馏作用强于大洋、超俯冲带和克拉通外岩石圈地幔，Se和Te含量也处于最低水平。高亲铁元素(HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au)及其嵌入的放射性衰变系统对氧逸度(fo2)，硫逸度(fs2)和压力(P)变化的不同响应，特别是通过这些参数对主要含硒硫化物和合金相稳定性的影响，使它们成为其熔化环境的潜在强大示踪剂。因此，研究克拉通地幔橄榄岩的HSE系统，结合Re-Os同位素的时间整合富集或衰竭信息，可以帮助我们了解太古宙地幔分异和大陆岩石圈形成的过程，这一问题在几十年的研究中一直存在争议。克拉通岩石圈的长寿意味着有足够的机会进行二次套印，模糊了我们对早期过程的看法。例如，在一些克拉通地幔样品中，铂族元素(PGE: Os, Ir, Ru, Rh, Pt, Pd)合金的失稳导致相容的PGE和Pt的耗尽，可能发生在氧化地幔楔中，或者通过与氧化小体积、富含挥发物的熔体相互作用，这些熔体通常侵入克拉通根部。这些熔体可能最终沉积S、Pd、Pt和Re，并捕获剩余的PGE合金，这与许多金伯利岩捕虏体的异常富S特征一致。玄武岩上的对应物显示出地面脱气的额外后期效应，可以耗尽挥发性元素(S, Re, Os)。玄武岩熔体也可以在硫化物不饱和的情况下清除PGE合金。这样的融化，可能……
{"title":"Distribution and Processing of Highly Siderophile Elements in Cratonic Mantle Lithosphere","authors":"S. Aulbach, J. Mungall, D. G. Pearson","doi":"10.2138/RMG.2016.81.5","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.5","url":null,"abstract":"Cratonic lithospheric mantle is composed of predominantly refractory materials that formed at higher mantle potential temperatures ( T P) than recorded in non-cratonic peridotites. It also shows stronger depletion and fractionation of Pd and Pt from Ru, Os and Ir than oceanic, supra-subduction zone or off-cratonic lithospheric mantle, as well as some of the lowest Se and Te contents. The varied response of the highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au), and their embedded radioactive decay systems, to changes in oxygen fugacity ( f O2), sulfur fugacity ( f S2) and pressure ( P )—in particular through the impact of these parameters on the stability of the main HSE-bearing sulfide and alloy phases makes them potentially powerful tracers of their melting environment. Therefore, investigation of the HSE systematics of cratonic mantle peridotites, in combination with information from Re–Os isotopes on time-integrated enrichment or depletion, can help us to understand processes leading to mantle differentiation and continental lithosphere formation in the Archean, which are controversial subjects despite decades of research. The longevity of the cratonic lithosphere implies that there was ample opportunity for secondary overprint, obscuring our view of earlier processes. For example, destabilization of platinum-group element (PGE: Os, Ir, Ru, Rh, Pt, Pd) alloy leading to depletions in the compatible PGE, and perhaps Pt, in some cratonic mantle samples may occur in an oxidizing mantle wedge or through interaction with oxidizing small-volume, volatile-rich melts that typically invade cratonic roots. Such melts may eventually deposit S, Pd, Pt and Re and also capture remaining PGE alloys, consistent with the anomalous S-rich character of many kimberlite-borne xenoliths. Their basalt-borne counterparts show additional late effects of subaerial degassing that can deplete volatile elements (S, Re, Os). Basaltic melts can also scavenge PGE alloys at depth, while still sulfide-undersaturated. Such melts, may, …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"60 1","pages":"239-304"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89177325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The platinum-group elements (PGEs; Os, Ir, Ru, Rh, Pt, Pd), along with rhenium and gold, are grouped together as the highly siderophile elements (HSEs), defined by their extreme partitioning into the metallic, relative to the oxide phase (> 104). The HSEs are highly refractory, as gauged by their high melting and condensation temperatures, and were therefore relatively concentrated in the feedstock for the terrestrial planets, as defined by the composition of chondritic meteorites (e.g., Anders and Ebihara 1982; Horan et al. 2003; Fischer-Godde et al. 2010). However, the planetary formation and differentiation process has since acted on this chemical group to produce a rich variety of absolute and relative inter-element fractionations. For example, analysis of iron meteorites suggests a significant decoupling of the HSE in the cores of planetesimals, and likely Earth’s core, with Os, Ir, Ru (IPGE-group) and Re concentrated in the metal phase, and Pt, Rh, Pd (PPGE-group) plus Au usually concentrated in the residual liquid (Goldstein et al. 2009). In terms of the silicate Earth, analysis of mantle rocks reveals very low levels of the HSE, but relative abundances similar to chondrites (see review by Day et al. 2016, this volume), in part reflecting HSE segregation into core-forming iron (Ringwood 1966; Ganapathy et al. 1970). This is in contrast to mantle-derived melts, whose HSE abundances are highly fractionated, with relative depletions in the IPGE-group compared to PPGE-group, as well as Re and Au (Barnes et al. 1985). Resulting Re/Os and Pt/Os fractionation also influence the long-term evolution of the 187Re to 187Os and 190Pt to 186Os decay systems, and, hence, the development of distinctive Os-isotope reservoirs (Walker et al. 1997; Shirey and Walker 1998; Day 2013). The emplacement of mantle-derived magmas into Earth’s crust results in …
铂族元素(PGEs;Os, Ir, Ru, Rh, Pt, Pd)，以及铼和金，被归类为高度亲铁元素(hsse)，由它们相对于氧化物相(> 104)的极端分配到金属中来定义。根据球粒陨石的组成(例如，Anders and Ebihara 1982;Horan et al. 2003;fisher - godde et al. 2010)。然而，行星的形成和分化过程自此作用于这一化学群，产生了丰富多样的绝对和相对元素间分馏。例如，对铁陨石的分析表明，星子核心(很可能是地核)中的HSE存在明显的解耦，Os、Ir、Ru (IPGE-group)和Re集中在金属相中，而Pt、Rh、Pd (PPGE-group)和Au通常集中在残液中(Goldstein etal . 2009)。就硅酸盐地球而言，对地幔岩石的分析显示，HSE含量非常低，但相对丰度与球粒陨石相似(见Day等人2016年的评论，本卷)，部分反映了HSE分离成核形成铁(Ringwood 1966;Ganapathy et al. 1970)。这与地幔源熔体相反，地幔源熔体的HSE丰度是高度分散的，与ppge组相比，ipge组相对减少，Re和Au也相对减少(Barnes et al. 1985)。由此产生的Re/Os和Pt/Os分馏也影响了187Re - 187Os和190Pt - 186Os衰变系统的长期演化，从而影响了独特的Os同位素储层的发育(Walker等，1997;Shirey and Walker 1998;天,2013)。地幔岩浆进入地壳的位置导致…
{"title":"Experimental Results on Fractionation of the Highly Siderophile Elements (HSE) at Variable Pressures and Temperatures during Planetary and Magmatic Differentiation","authors":"J. Brenan, N. Bennett, Z. Zajacz","doi":"10.2138/RMG.2016.81.1","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.1","url":null,"abstract":"The platinum-group elements (PGEs; Os, Ir, Ru, Rh, Pt, Pd), along with rhenium and gold, are grouped together as the highly siderophile elements (HSEs), defined by their extreme partitioning into the metallic, relative to the oxide phase (> 104). The HSEs are highly refractory, as gauged by their high melting and condensation temperatures, and were therefore relatively concentrated in the feedstock for the terrestrial planets, as defined by the composition of chondritic meteorites (e.g., Anders and Ebihara 1982; Horan et al. 2003; Fischer-Godde et al. 2010). However, the planetary formation and differentiation process has since acted on this chemical group to produce a rich variety of absolute and relative inter-element fractionations. For example, analysis of iron meteorites suggests a significant decoupling of the HSE in the cores of planetesimals, and likely Earth’s core, with Os, Ir, Ru (IPGE-group) and Re concentrated in the metal phase, and Pt, Rh, Pd (PPGE-group) plus Au usually concentrated in the residual liquid (Goldstein et al. 2009). In terms of the silicate Earth, analysis of mantle rocks reveals very low levels of the HSE, but relative abundances similar to chondrites (see review by Day et al. 2016, this volume), in part reflecting HSE segregation into core-forming iron (Ringwood 1966; Ganapathy et al. 1970). This is in contrast to mantle-derived melts, whose HSE abundances are highly fractionated, with relative depletions in the IPGE-group compared to PPGE-group, as well as Re and Au (Barnes et al. 1985). Resulting Re/Os and Pt/Os fractionation also influence the long-term evolution of the 187Re to 187Os and 190Pt to 186Os decay systems, and, hence, the development of distinctive Os-isotope reservoirs (Walker et al. 1997; Shirey and Walker 1998; Day 2013). The emplacement of mantle-derived magmas into Earth’s crust results in …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"1 1","pages":"1-87"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82964699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mantle sulfides (Fe–Ni–Cu-rich base metal sulfides or BMS; Fig. 1) play a crucial role in the distribution of Re, Os, and Pb in mantle rocks and are thus fundamental to obtaining absolute ages by direct geochronology using the Re–Os and Pb–Pb isotope systems on mantle samples. Mantle samples exist as hundreds of exposures of peridotites, pyroxenites and diamonds, either brought to the surface as accidental xenoliths and xenocrysts during kimberlitic or alkali basaltic volcanism (for comprehensive reviews, see Pearson et al. 2014; Aulbach et al. 2016, this volume; Luguet and Reisberg 2016, this volume), or as orogenic, ophiolitic and abyssal peridotite obducted at convergent margins and drilled / dredged from oceanic basins (e.g., Bodinier and Godard 2014; Becker and Dale 2016, this volume). This chapter reviews the occurrence of BMS in mantle samples and the role that they play in controlling the Re–Os and Pb isotope systematics of the mantle. Included in this review is a discussion of the role BMS plays in recording the multiple depletion / enrichment / metasomatic events that the mantle has undergone and the preservation of chemical heterogeneities that are inherently created by these processes. Along with discussions of the utility of Re–Os and Pb isotope measurements, this review will also consider the potential pitfalls and some of the surprises that can arise when analyzing these BMS micro-phases. Specifically excluded from this review is the extensive literature on Re–Os and Pb for the geochronology of sulfide systems in magmatic ores. This study is another field entirely from the study of sulfides in their native mantle hosts because of the complicated magmatic concentration processes occurring at crustal levels. Figure 1 Backscattered electron and chemical maps of typical mantle BMS grains. (a) Enclosed; (b) interstitial BMS, both from Mt Gambier peridotites, SE Australia (Alard …
地幔硫化物(富fe - ni - cu贱金属硫化物或BMS);图1)对地幔岩石中Re、Os和Pb的分布起着至关重要的作用，因此是利用地幔样品上的Re - Os和Pb - Pb同位素系统通过直接地质年代学获得绝对年龄的基础。地幔样本以数百种暴露的橄榄岩、辉石岩和钻石的形式存在，它们要么是在金伯利岩或碱玄武岩火山作用期间作为意外的包体和包体带到地表的(有关全面评论，见Pearson et al. 2014;Aulbach et al. 2016，本卷;Luguet和Reisberg 2016，本卷)，或作为造山岩、蛇绿岩和深海橄榄岩在会聚边缘倒转并从海洋盆地钻探/疏浚(例如，Bodinier和Godard 2014;Becker and Dale 2016，本卷)。本章综述了BMS在地幔样品中的赋存状态及其对地幔Re-Os和Pb同位素系统的控制作用。本文讨论了BMS在记录地幔所经历的多次枯竭/富集/交代事件以及保存这些过程固有的化学非均质性方面所起的作用。除了讨论Re-Os和Pb同位素测量的实用性外，本文还将考虑在分析这些BMS微相时可能出现的潜在缺陷和一些意外情况。本文特别排除了大量关于岩浆矿石中硫化物系统年代学的Re-Os和Pb的文献。由于地壳水平岩浆富集过程复杂，本研究完全不同于对原生地幔寄主硫化物的研究。图1典型地幔BMS颗粒的背散射电子图和化学图。(一)封闭;(b)间隙质BMS，均来自澳大利亚东南部的Mt Gambier橄榄岩(Alard…
{"title":"Mantle Sulfides and their Role in Re–Os and Pb Isotope Geochronology","authors":"J. Harvey, J. Warren, S. Shirey","doi":"10.2138/RMG.2016.81.10","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.10","url":null,"abstract":"Mantle sulfides (Fe–Ni–Cu-rich base metal sulfides or BMS; Fig. 1) play a crucial role in the distribution of Re, Os, and Pb in mantle rocks and are thus fundamental to obtaining absolute ages by direct geochronology using the Re–Os and Pb–Pb isotope systems on mantle samples. Mantle samples exist as hundreds of exposures of peridotites, pyroxenites and diamonds, either brought to the surface as accidental xenoliths and xenocrysts during kimberlitic or alkali basaltic volcanism (for comprehensive reviews, see Pearson et al. 2014; Aulbach et al. 2016, this volume; Luguet and Reisberg 2016, this volume), or as orogenic, ophiolitic and abyssal peridotite obducted at convergent margins and drilled / dredged from oceanic basins (e.g., Bodinier and Godard 2014; Becker and Dale 2016, this volume). This chapter reviews the occurrence of BMS in mantle samples and the role that they play in controlling the Re–Os and Pb isotope systematics of the mantle. Included in this review is a discussion of the role BMS plays in recording the multiple depletion / enrichment / metasomatic events that the mantle has undergone and the preservation of chemical heterogeneities that are inherently created by these processes. Along with discussions of the utility of Re–Os and Pb isotope measurements, this review will also consider the potential pitfalls and some of the surprises that can arise when analyzing these BMS micro-phases. Specifically excluded from this review is the extensive literature on Re–Os and Pb for the geochronology of sulfide systems in magmatic ores. This study is another field entirely from the study of sulfides in their native mantle hosts because of the complicated magmatic concentration processes occurring at crustal levels. Figure 1 Backscattered electron and chemical maps of typical mantle BMS grains. (a) Enclosed; (b) interstitial BMS, both from Mt Gambier peridotites, SE Australia (Alard …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"19 1","pages":"579-649"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86588958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The highly siderophile elements (HSE) include the fifth-period transition metals ruthenium (Ru), rhodium (Rh), palladium (Pd), and the sixth-period transition metals rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt) and gold (Au). In addition to being iron-loving, these elements are also resistant to oxidation, have high melting temperatures and are important as industrial catalysts. HSE abundances in geologic materials vary significantly, ranging from ~1 mg/g in ore materials down to a few pg/g in basalts (Table 1). These elements comprise two long-lived radiometric decay schemes: 187Re decays to 187Os, and 190Pt decays to 186Os. View this table: Table 1 Range of HSE abundances, in ng/g, in selected rock types and in model upper mantle. The HSE have been targeted to address a wide variety of geochemical and cosmochemical questions. Early work suggested HSE concentrations can constrain Hadean mantle evolution (Chou 1978) and showed the geochronologic potential of the Re/Os isotope system (Herr and Merz 1955; Herr et al. 1961; Markey et al. 1998). More recent applications combine the Re–Os decay system with abundance data for the HSE to investigate the evolution of the planets and the moon (Day et al. 2010, 2016, this volume), the terrestrial mantle (Rehkamper et al. 1997; Aulbach et al. 2016, this volume; Harvey et al. 2016, this volume; Luguet and Reisberg 2016, this volume), impact craters (Koeberl and Shirey 1993), geochemistry and geochronology of ore formation (Markey et al. 1998; Barnes and Ripley 2016, this volume), tektites (Koeberl and Shirey 1993), as well as the formation and evolution of the continental curst (e.g., Peucker-Ehrenbrink and Jahn 2001). Non-mass dependent isotope variations in Re, Os, Ru, Pt and Pd are also present in some meteorites and lunar samples and arise from nucleosynthesis and cosmogenic radiation (Yokoyama and …
高亲铁元素(HSE)包括第五代过渡金属钌(Ru)、铑(Rh)、钯(Pd)和第六代过渡金属铼(Re)、锇(Os)、铱(Ir)、铂(Pt)和金(Au)。除了亲铁之外，这些元素还具有抗氧化性，熔点高，是重要的工业催化剂。地质物质中的HSE丰度变化很大，从矿石中的~ 1mg /g到玄武岩中的几pg/g不等(表1)。这些元素包括两种长寿命的放射性衰变方案:187Re衰变到187Os, 190Pt衰变到186Os。表1选定岩石类型和模型上地幔中HSE丰度范围，单位为ng/g。HSE旨在解决各种各样的地球化学和宇宙化学问题。早期的研究表明，HSE浓度可以限制冥古宙地幔演化(Chou 1978)，并显示了Re/Os同位素系统的地质年代学潜力(Herr和Merz 1955;Herr et al. 1961;Markey et al. 1998)。最近的应用将Re-Os衰变系统与HSE的丰富数据相结合，以研究行星和月球的演化(Day等人，2010年，2016年，本卷)，地幔(Rehkamper等人，1997年;Aulbach et al. 2016，本卷;Harvey et al. 2016，本卷;Luguet and Reisberg 2016，本卷)，撞击坑(Koeberl and Shirey 1993)，成矿的地球化学和地质年代学(Markey et al. 1998;Barnes and Ripley 2016，本卷)，tektites (Koeberl and Shirey 1993)，以及大陆地壳的形成和演化(例如，Peucker-Ehrenbrink and Jahn 2001)。Re, Os, Ru, Pt和Pd的非质量依赖同位素变化也存在于一些陨石和月球样品中，这是由核合成和宇宙辐射引起的(Yokoyama和…
{"title":"Analytical Methods for the Highly Siderophile Elements","authors":"T. Meisel, M. Horan","doi":"10.2138/RMG.2016.81.02","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.02","url":null,"abstract":"The highly siderophile elements (HSE) include the fifth-period transition metals ruthenium (Ru), rhodium (Rh), palladium (Pd), and the sixth-period transition metals rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt) and gold (Au). In addition to being iron-loving, these elements are also resistant to oxidation, have high melting temperatures and are important as industrial catalysts. HSE abundances in geologic materials vary significantly, ranging from ~1 mg/g in ore materials down to a few pg/g in basalts (Table 1). These elements comprise two long-lived radiometric decay schemes: 187Re decays to 187Os, and 190Pt decays to 186Os. View this table: Table 1 Range of HSE abundances, in ng/g, in selected rock types and in model upper mantle. The HSE have been targeted to address a wide variety of geochemical and cosmochemical questions. Early work suggested HSE concentrations can constrain Hadean mantle evolution (Chou 1978) and showed the geochronologic potential of the Re/Os isotope system (Herr and Merz 1955; Herr et al. 1961; Markey et al. 1998). More recent applications combine the Re–Os decay system with abundance data for the HSE to investigate the evolution of the planets and the moon (Day et al. 2010, 2016, this volume), the terrestrial mantle (Rehkamper et al. 1997; Aulbach et al. 2016, this volume; Harvey et al. 2016, this volume; Luguet and Reisberg 2016, this volume), impact craters (Koeberl and Shirey 1993), geochemistry and geochronology of ore formation (Markey et al. 1998; Barnes and Ripley 2016, this volume), tektites (Koeberl and Shirey 1993), as well as the formation and evolution of the continental curst (e.g., Peucker-Ehrenbrink and Jahn 2001). Non-mass dependent isotope variations in Re, Os, Ru, Pt and Pd are also present in some meteorites and lunar samples and arise from nucleosynthesis and cosmogenic radiation (Yokoyama and …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"79 1","pages":"89-106"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88989386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An ore deposit by definition must be economically viable, that is to say it must contain sufficient material at high enough grade to make it possible to mine and process it at a profit (Bates and Jackson 1987). This requires the elements to be collected and concentrated by some phase and for them to be deposited close to the surface of the earth. At the oxygen fugacities found in the crust, native Fe is not normally stable and thus the highly siderophile elements (defined as Ru, Rh, Pd, Re, Os, Ir, Pt, and Au) cannot behave as siderophile elements except in rare cases such as on Disko Island (Klock et al. 1986) where the magma is sufficiently reduced for native Fe to be present. However, if mafic magmas become saturated in a base-metal-sulfide liquid, the highly siderophile elements behave as highly chalcophile elements (Table 1). Thus these elements are generally found in association with base-metal-sulfide minerals which crystallized from a magmatic sulfide liquid, namely pyrrhotite, pentlandite, chalcopyrite, cubanite ± pyrite. An exception to this is Au. Although Au is strongly chalcophile and is produced as a by-product from many platinum-group element (PGE) deposits (Table 2), most primary Au deposits consist of native Au (Groves et al. 1998). These will not be discussed in this chapter. There are many PGE-deposits (i.e., accumulations of PGE minerals and base metal sulfides containing PGE; Bates and Jackson 1987) around the world, but most of these do not constitute PGE ore deposits, because they are either too small or their grade is too low, or other political or infrastructure factors prevent the economic exploitation of the deposit (Bates and Jackson 1987) For the purpose of this work we have defined PGE ore deposits as those which have significant production (> 2% of the annual world …
根据定义，一个矿床必须在经济上可行，也就是说，它必须含有足够高品位的材料，使其开采和加工有可能获利(Bates和Jackson 1987)。这就要求这些元素经过某种阶段的收集和浓缩，并在靠近地球表面的地方沉积下来。在地壳中发现的氧逸度下，天然铁通常不稳定，因此高度亲铁元素(定义为Ru, Rh, Pd, Re, Os, Ir, Pt和Au)不能表现为亲铁元素，除非在罕见的情况下，如在迪斯科岛(Klock et al. 1986)，岩浆被充分还原，使天然铁存在。然而，如果基性岩浆在碱性金属硫化物液体中饱和，则高亲铁元素表现为高亲铜元素(表1)。因此，这些元素通常与岩浆硫化物液体结晶的碱性金属硫化物矿物相结合，即磁黄铁矿、镍黄铁矿、黄铜矿、cubanite±黄铁矿。Au是一个例外。虽然金具有很强的亲铜性，是许多铂族元素(PGE)矿床的副产品(表2)，但大多数原生金矿由天然金组成(Groves et al. 1998)。本章不讨论这些问题。有许多PGE矿床(即PGE矿物和含有PGE的贱金属硫化物的堆积);Bates and Jackson 1987)，但其中大多数不构成PGE矿床，因为它们要么太小，要么品位太低，或者其他政治或基础设施因素阻碍了矿床的经济开采(Bates and Jackson 1987)。为了这项工作的目的，我们将PGE矿床定义为具有显著产量的矿床(>世界年产量的2%)。
{"title":"Highly Siderophile and Strongly Chalcophile Elements in Magmatic Ore Deposits","authors":"S. Barnes, E. Ripley","doi":"10.2138/RMG.2016.81.12","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.12","url":null,"abstract":"An ore deposit by definition must be economically viable, that is to say it must contain sufficient material at high enough grade to make it possible to mine and process it at a profit (Bates and Jackson 1987). This requires the elements to be collected and concentrated by some phase and for them to be deposited close to the surface of the earth. At the oxygen fugacities found in the crust, native Fe is not normally stable and thus the highly siderophile elements (defined as Ru, Rh, Pd, Re, Os, Ir, Pt, and Au) cannot behave as siderophile elements except in rare cases such as on Disko Island (Klock et al. 1986) where the magma is sufficiently reduced for native Fe to be present. However, if mafic magmas become saturated in a base-metal-sulfide liquid, the highly siderophile elements behave as highly chalcophile elements (Table 1). Thus these elements are generally found in association with base-metal-sulfide minerals which crystallized from a magmatic sulfide liquid, namely pyrrhotite, pentlandite, chalcopyrite, cubanite ± pyrite. An exception to this is Au. Although Au is strongly chalcophile and is produced as a by-product from many platinum-group element (PGE) deposits (Table 2), most primary Au deposits consist of native Au (Groves et al. 1998). These will not be discussed in this chapter. There are many PGE-deposits (i.e., accumulations of PGE minerals and base metal sulfides containing PGE; Bates and Jackson 1987) around the world, but most of these do not constitute PGE ore deposits, because they are either too small or their grade is too low, or other political or infrastructure factors prevent the economic exploitation of the deposit (Bates and Jackson 1987) For the purpose of this work we have defined PGE ore deposits as those which have significant production (> 2% of the annual world …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"23 1","pages":"725-774"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88556119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tectonically emplaced mantle rocks, such as ophiolites, abyssal peridotites, and orogenic peridotite massifs, provide a principle constraint on the composition of and processes in the Earth’s upper mantle (Bodinier and Godard 2003). In the past, these ‘mantle tectonites’ have sometimes received different names because their history and origin has been unclear. Mantle tectonites are now understood to reflect a range of geologic environments regarding their emplacement and their origin (e.g., Dilek and Furnes 2014). The advantage of these rocks compared to mantle xenoliths is the large-scale exposure of textural and compositional relations between different rock types that can be used to identify processes such as melting, magma or fluid transport, chemical reactions, mixing or deformation at a range of spatial scales. A disadvantage of most mantle tectonites is that they commonly display substantial chemical modification of some elements, resulting from widespread serpentinization at low temperatures. In some cases, this may also affect abundances of several of the highly siderophile elements (HSE: Re, Au, PGE: Os, Ir, Ru, Rh, Pt, Pd), however, this can be tested by comparison with unaltered rocks of similar composition. As is discussed in Luguet and Reisberg (2016, this volume), Harvey et al. (2016, this volume) and Aulbach et al. (2016, this volume), peridotite xenoliths have their own alteration issues regarding sulfides and chalcophile elements. Numerous studies have obtained Os isotope and/or highly siderophile element abundance data on many different types of mantle tectonites. Some of these studies have focused on large-scale chemical and isotopic variations, others on grain size-scale compositional variations to understand small-scale distribution processes. These studies have, together, significantly advanced the understanding of the processes that fractionate the HSE in the mantle at different spatial scales and have provided insights into the behavior of sulfide in the mantle—the phase that typically …
构造侵位的地幔岩石，如蛇绿岩、深海橄榄岩和造山橄榄岩块，对地球上地幔的组成和过程提供了一个原则性的约束(Bodinier和Godard 2003)。在过去，这些“地幔构造岩”有时会有不同的名字，因为它们的历史和起源一直不清楚。地幔构造岩现在被理解为反映了一系列关于其就位和起源的地质环境(例如，Dilek和Furnes 2014)。与地幔捕虏体相比，这些岩石的优势在于可以大规模地揭示不同岩石类型之间的结构和成分关系，这些关系可用于识别熔融、岩浆或流体运输、化学反应、混合或在一定空间尺度上的变形等过程。大多数地幔构造岩的一个缺点是，它们通常表现出一些元素的实质性化学修饰，这是由于在低温下广泛的蛇纹石化造成的。在某些情况下，这也可能影响一些高度亲铁元素的丰度(HSE: Re, Au, PGE: Os, Ir, Ru, Rh, Pt, Pd)，然而，这可以通过与相似组成的未蚀变岩石进行比较来测试。正如Luguet和Reisberg(2016，本卷)、Harvey等人(2016，本卷)和Aulbach等人(2016，本卷)所讨论的那样，橄榄岩捕虏体在硫化物和亲铜元素方面有自己的蚀变问题。许多研究已经在许多不同类型的地幔构造岩上获得了Os同位素和/或高亲铁元素丰度数据。其中一些研究集中在大尺度的化学和同位素变化上，另一些研究集中在粒度尺度的成分变化上，以了解小尺度的分布过程。这些研究共同极大地推进了对地幔中HSE在不同空间尺度上的分馏过程的理解，并为地幔中硫化物的行为提供了见解。
{"title":"Re–Pt–Os Isotopic and Highly Siderophile Element Behavior in Oceanic and Continental Mantle Tectonites","authors":"Tectonites, H. Becker, C. Dale","doi":"10.2138/RMG.2016.81.7","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.7","url":null,"abstract":"Tectonically emplaced mantle rocks, such as ophiolites, abyssal peridotites, and orogenic peridotite massifs, provide a principle constraint on the composition of and processes in the Earth’s upper mantle (Bodinier and Godard 2003). In the past, these ‘mantle tectonites’ have sometimes received different names because their history and origin has been unclear. Mantle tectonites are now understood to reflect a range of geologic environments regarding their emplacement and their origin (e.g., Dilek and Furnes 2014). The advantage of these rocks compared to mantle xenoliths is the large-scale exposure of textural and compositional relations between different rock types that can be used to identify processes such as melting, magma or fluid transport, chemical reactions, mixing or deformation at a range of spatial scales. A disadvantage of most mantle tectonites is that they commonly display substantial chemical modification of some elements, resulting from widespread serpentinization at low temperatures. In some cases, this may also affect abundances of several of the highly siderophile elements (HSE: Re, Au, PGE: Os, Ir, Ru, Rh, Pt, Pd), however, this can be tested by comparison with unaltered rocks of similar composition. As is discussed in Luguet and Reisberg (2016, this volume), Harvey et al. (2016, this volume) and Aulbach et al. (2016, this volume), peridotite xenoliths have their own alteration issues regarding sulfides and chalcophile elements. Numerous studies have obtained Os isotope and/or highly siderophile element abundance data on many different types of mantle tectonites. Some of these studies have focused on large-scale chemical and isotopic variations, others on grain size-scale compositional variations to understand small-scale distribution processes. These studies have, together, significantly advanced the understanding of the processes that fractionate the HSE in the mantle at different spatial scales and have provided insights into the behavior of sulfide in the mantle—the phase that typically …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"70 1","pages":"369-440"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86296991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The highly siderophile elements (HSE) consist of the Platinum Group Elements (PGE: Ru, Rh, Pd, Os, Ir, Pt) along with rhenium and gold. These transition elements show relative chemical inertness and high market values, which respectively earned them the additional names of noble metals and precious metals. The HSE show a very pronounced affinity for iron metal, which translates into metal/silicate partition coefficients similar to or higher than 10,000 over large ranges of both pressure and temperature (e.g., O’Neill et al. 1995; Borisov and Palme 2000; Ertel et al. 1999, 2001, 2006, 2008; Fortenfant et al. 2003, 2006; Brenan et al. 2005; Cottrell and Walker 2006; Brenan and McDonough 2009; Laurenz et al. 2010; Mann et al. 2012; see Brenan et al. 2016, this volume for detailed review). Consequently, the HSE are thought to have been efficiently sequestered within the metallic core of our planet during the metal–silicate differentiation of Earth, leaving the silicate counterpart almost HSE-barren. Investigations of mantle peridotites since the 1970s revealed ng.g−1 level abundances as well as close-to-chondritic proportions of the HSE (Chou 1978; Jagoutz et al. 1979; Mitchell and Keays 1981; McDonough and Sun 1995; Becker et al. 2006; Fischer-Godde et al. 2011). Such abundances and inter-HSE fractionations are not predicted for the silicate Earth left after separation of the metallic core for low- or high-pressure core–mantle differentiation (see Brenan et al. 2016, this volume). The close agreement between the osmium isotopic compositions of fertile mantle peridotites and those of chondritic meteorites (Walker et al. 2002a), which requires nearly identical Re/Os ratios in these two reservoirs, provides particularly convincing evidence that the mantle’s HSE content cannot simply represent the residue left after core formation. …
高亲铁元素(HSE)由铂族元素(PGE: Ru, Rh, Pd, Os, Ir, Pt)以及铼和金组成。这些过渡元素具有相对的化学惰性和较高的市场价值，分别被称为贵金属和贵金属。HSE对铁金属表现出非常明显的亲和力，在很大的压力和温度范围内，金属/硅酸盐分割系数接近或高于10,000(例如，O 'Neill等人，1995;鲍里索夫和帕尔梅2000;Ertel等，1999,2001,2006,2008;Fortenfant等人，2003,2006;Brenan et al. 2005;Cottrell and Walker 2006;Brenan and McDonough 2009;Laurenz et al. 2010;Mann et al. 2012;参见Brenan et al. 2016，本卷详细审查)。因此，在地球的金属硅酸盐分化过程中，HSE被认为有效地隔离在地球的金属核心中，使得硅酸盐对应的HSE几乎是贫瘠的。自20世纪70年代以来对地幔橄榄岩的研究表明。g−1水平丰度以及HSE的接近线粒体比例(Chou 1978;Jagoutz et al. 1979;Mitchell and Keays 1981;McDonough and Sun 1995;Becker et al. 2006;fisher - godde et al. 2011)。对于低或高压核幔分异过程中金属岩心分离后留下的硅酸盐土，无法预测这种丰度和hse间分异(见Brenan etal . 2016，本卷)。沃土橄榄岩的锇同位素组成与球粒陨石的锇同位素组成非常接近(Walker et al. 2002a)，这要求这两个储层的Re/Os比率几乎相同，这提供了特别有说服力的证据，表明地幔的HSE含量不能简单地代表岩心形成后留下的残留物。…
{"title":"Highly Siderophile Element and 187Os Signatures in Non-cratonic Basalt-hosted Peridotite Xenoliths: Unravelling the Origin and Evolution of the Post-Archean Lithospheric Mantle","authors":"A. Luguet, L. Reisberg","doi":"10.2138/RMG.2016.81.06","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.06","url":null,"abstract":"The highly siderophile elements (HSE) consist of the Platinum Group Elements (PGE: Ru, Rh, Pd, Os, Ir, Pt) along with rhenium and gold. These transition elements show relative chemical inertness and high market values, which respectively earned them the additional names of noble metals and precious metals. The HSE show a very pronounced affinity for iron metal, which translates into metal/silicate partition coefficients similar to or higher than 10,000 over large ranges of both pressure and temperature (e.g., O’Neill et al. 1995; Borisov and Palme 2000; Ertel et al. 1999, 2001, 2006, 2008; Fortenfant et al. 2003, 2006; Brenan et al. 2005; Cottrell and Walker 2006; Brenan and McDonough 2009; Laurenz et al. 2010; Mann et al. 2012; see Brenan et al. 2016, this volume for detailed review). Consequently, the HSE are thought to have been efficiently sequestered within the metallic core of our planet during the metal–silicate differentiation of Earth, leaving the silicate counterpart almost HSE-barren. Investigations of mantle peridotites since the 1970s revealed ng.g−1 level abundances as well as close-to-chondritic proportions of the HSE (Chou 1978; Jagoutz et al. 1979; Mitchell and Keays 1981; McDonough and Sun 1995; Becker et al. 2006; Fischer-Godde et al. 2011). Such abundances and inter-HSE fractionations are not predicted for the silicate Earth left after separation of the metallic core for low- or high-pressure core–mantle differentiation (see Brenan et al. 2016, this volume). The close agreement between the osmium isotopic compositions of fertile mantle peridotites and those of chondritic meteorites (Walker et al. 2002a), which requires nearly identical Re/Os ratios in these two reservoirs, provides particularly convincing evidence that the mantle’s HSE content cannot simply represent the residue left after core formation. …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"27 1","pages":"305-367"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82304567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au) are key tracers of planetary accretion and differentiation processes due to their affinity for metal relative to silicate. Under low-pressure conditions the HSE are defined by having metal–silicate partition coefficients in excess of 104 (e.g., Kimura et al. 1974; Jones and Drake 1986; O’Neill et al. 1995; Borisov and Palme 1997; Mann et al. 2012). The HSE are geochemically distinct in that, with the exception of Au, they have elevated melting points relative to iron (1665 K), low vapour pressures, and are resistant to corrosion or oxidation. Under solar nebular conditions, Re, Os, Ir, Ru, Rh, and Pt, along with the moderately siderophile elements (MSE) Mo and W, condense as refractory-metal alloys. Palladium and Au are not as refractory and condense in solid solution with FeNi metal (Palme 2008). Assuming abundances of the HSE in materials that made up the bulk Earth were broadly similar to modern chondrite meteorites, mass balance calculations suggest that >98% of these elements reside in the metallic core (O’Neill and Palme 1998). In practical terms, the resultant low HSE abundance inventories in differentiated silicate crusts and mantles enables the use of these elements in order to effectively track metallic core formation and the subsequent additions of HSE-rich impactors to planets and asteroids (Fig. 1). In detail, the absolute and relative abundances of the HSE in planetary materials are also affected by mantle and crustal processes including melting, metasomatism, fractional crystallization, and crust-mantle remixing, as well as later impact processing, volatility of Re under oxidizing conditions, and low-temperature secondary alteration (cf., Day 2013; Gannoun et al. 2016, this volume). In the absence of metal, the HSE are chalcophile, so these elements are also affected by processes …
{"title":"Highly Siderophile Elements in Earth, Mars, the Moon, and Asteroids.","authors":"James M D Day, Alan D Brandon, Richard J Walker","doi":"10.2138/rmg.2016.81.04","DOIUrl":"10.2138/rmg.2016.81.04","url":null,"abstract":"The highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, Pd, Re, Au) are key tracers of planetary accretion and differentiation processes due to their affinity for metal relative to silicate. Under low-pressure conditions the HSE are defined by having metal–silicate partition coefficients in excess of 104 (e.g., Kimura et al. 1974; Jones and Drake 1986; O’Neill et al. 1995; Borisov and Palme 1997; Mann et al. 2012). The HSE are geochemically distinct in that, with the exception of Au, they have elevated melting points relative to iron (1665 K), low vapour pressures, and are resistant to corrosion or oxidation. Under solar nebular conditions, Re, Os, Ir, Ru, Rh, and Pt, along with the moderately siderophile elements (MSE) Mo and W, condense as refractory-metal alloys. Palladium and Au are not as refractory and condense in solid solution with FeNi metal (Palme 2008). Assuming abundances of the HSE in materials that made up the bulk Earth were broadly similar to modern chondrite meteorites, mass balance calculations suggest that >98% of these elements reside in the metallic core (O’Neill and Palme 1998). In practical terms, the resultant low HSE abundance inventories in differentiated silicate crusts and mantles enables the use of these elements in order to effectively track metallic core formation and the subsequent additions of HSE-rich impactors to planets and asteroids (Fig. 1). In detail, the absolute and relative abundances of the HSE in planetary materials are also affected by mantle and crustal processes including melting, metasomatism, fractional crystallization, and crust-mantle remixing, as well as later impact processing, volatility of Re under oxidizing conditions, and low-temperature secondary alteration (cf., Day 2013; Gannoun et al. 2016, this volume). In the absence of metal, the HSE are chalcophile, so these elements are also affected by processes …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"81 1","pages":"161-238"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2138/rmg.2016.81.04","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37216558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Numerous investigations have been devoted to understanding how the materials that contributed to the Solar System formed, were incorporated into the precursor molecular cloud and the protoplanetary disk, and ultimately evolved into the building blocks of planetesimals and planets. Chemical and isotopic analyses of extraterrestrial materials have played a central role in decoding the signatures of individual processes that led to their formation. Among the elements studied, the siderophile and chalcophile elements are crucial for considering a range of formational and evolutionary processes. Consequently, over the past 60 years, considerable effort has been focused on the development of abundance and isotopic analyses of these elements in terrestrial and extraterrestrial materials (e.g., Shirey and Walker 1995; Birck et al. 1997; Reisberg and Meisel 2002; Meisel and Horan 2016, this volume). In this review, we consider nucleosynthetic isotopic variability of siderophile and chalcophile elements in meteorites. Chapter 4 provides a review for siderophile and chalcophile elements in planetary materials in general (Day et al. 2016, this volume). In many cases, such variability is denoted as an “isotopic anomaly”; however, the term can be ambiguous because several pre- and post- Solar System formation processes can lead to variability of isotopic compositions as recorded in meteorites. Here we strictly define the term “isotopic anomaly” as referring to an isotopic deviation from the terrestrial composition resulting from the incorporation of varying proportions of elements with diverse nucleosynthetic origins into a meteorite component or parent body. The term will not be used here to refer to isotopic variations that result from mass-dependent isotopic fractionation, radioactive decay in the Solar System, or spallation effects. Based on astronomical observations and physical modelling, the formation of the Solar System has generally been thought to have initiated by the collapse of a dense molecular cloud …
{"title":"Nucleosynthetic Isotope Variations of Siderophile and Chalcophile Elements in the Solar System.","authors":"Tetsuya Yokoyama, Richard J Walker","doi":"10.2138/rmg.2016.81.03","DOIUrl":"10.2138/rmg.2016.81.03","url":null,"abstract":"Numerous investigations have been devoted to understanding how the materials that contributed to the Solar System formed, were incorporated into the precursor molecular cloud and the protoplanetary disk, and ultimately evolved into the building blocks of planetesimals and planets. Chemical and isotopic analyses of extraterrestrial materials have played a central role in decoding the signatures of individual processes that led to their formation. Among the elements studied, the siderophile and chalcophile elements are crucial for considering a range of formational and evolutionary processes. Consequently, over the past 60 years, considerable effort has been focused on the development of abundance and isotopic analyses of these elements in terrestrial and extraterrestrial materials (e.g., Shirey and Walker 1995; Birck et al. 1997; Reisberg and Meisel 2002; Meisel and Horan 2016, this volume).\u0000\u0000In this review, we consider nucleosynthetic isotopic variability of siderophile and chalcophile elements in meteorites. Chapter 4 provides a review for siderophile and chalcophile elements in planetary materials in general (Day et al. 2016, this volume). In many cases, such variability is denoted as an “isotopic anomaly”; however, the term can be ambiguous because several pre- and post- Solar System formation processes can lead to variability of isotopic compositions as recorded in meteorites. Here we strictly define the term “isotopic anomaly” as referring to an isotopic deviation from the terrestrial composition resulting from the incorporation of varying proportions of elements with diverse nucleosynthetic origins into a meteorite component or parent body. The term will not be used here to refer to isotopic variations that result from mass-dependent isotopic fractionation, radioactive decay in the Solar System, or spallation effects.\u0000\u0000Based on astronomical observations and physical modelling, the formation of the Solar System has generally been thought to have initiated by the collapse of a dense molecular cloud …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"81 1","pages":"107-160"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2138/rmg.2016.81.03","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36975582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The platinum-group minerals (PGM) are a diverse group of minerals that concentrate the platinum-group elements (PGE; Os, Ir, Ru, Rh, Pt, and Pd). At the time of writing, the International Mineralogical Association database includes 135 named discrete PGM phases. Much of our knowledge of the variety and the distribution of these minerals in natural systems comes from ore deposits associated with mafic and ultramafic rocks and their derivatives (see also Barnes and Ripley 2016, this volume). Concentrations of PGM can be found in layered mafic–ultramafic intrusions. Although they don’t typically achieve ore grade status, supra-subduction zone upper mantle (preserved in ophiolite) lithologies (i.e., chromitite [> 60 vol.% Cr-spinel], pyroxenite) characteristically host a diversity of PGM assemblages as well (Becker and Dale 2016, this volume). Occurrences of the PGM in layered intrusions, ophiolites, and several other important settings will all be described in this review. In keeping with the general theme of this volume, the focus of this chapter is on relatively high-temperature (magmatic) settings. This is not a straightforward distinction to make, as PGM assemblages that begin as high-temperature parageneses may be modified at much lower temperatures during metamorphism, hydrothermal processes or surficial weathering (e.g., Hanley 2005). However, the vast majority of the published literature on PGM petrogenesis is based on occurrences from magmatic environments, an understandable bias given the importance of the major ore deposits that occur in some layered mafic–ultramafic intrusions, for example. For that reason, the emphasis of this review will be on high-temperature magmatic settings, with the understanding that lower temperature (sub-solidus; < 600 °C) processes can modify primary PGM assemblages. The geochemical behavior of the platinum-group elements (PGE) in magmatic settings is highly chalcophile and not, as might be expected, highly siderophile. This is because most terrestrial magmatic systems are relatively oxidized, such …
铂族矿物(PGM)是一种富集铂族元素(PGE;Os, Ir, Ru, Rh, Pt和Pd)在撰写本文时，国际矿物学协会的数据库包括135个已命名的离散PGM相。我们对这些矿物在自然系统中的种类和分布的大部分知识来自与基性和超基性岩石及其衍生物相关的矿床(另见Barnes和Ripley 2016，本卷)。在层状基性-超基性侵入体中可以发现PGM的浓度。虽然它们通常没有达到矿石品位，但俯冲带上地幔(保存在蛇绿岩中)岩性(即铬铁矿[> 60 vol.% cr -尖晶石]，辉石岩)也具有多种PGM组合的特征(Becker and Dale 2016，本卷)。本文将介绍层状侵入体、蛇绿岩和其他重要环境中PGM的赋有情况。为了与本卷的总体主题保持一致，本章的重点是相对高温(岩浆)环境。这并不是一个简单的区分，因为在变质作用、热液作用或表面风化过程中，以高温共生的形式开始的PGM组合可能在更低的温度下被修饰(例如，Hanley 2005)。然而，绝大多数已发表的关于PGM岩石成因的文献都是基于岩浆环境的产状，考虑到主要矿床的重要性，例如在一些层状基性-超基性侵入体中，这种偏见是可以理解的。因此，本综述的重点将放在高温岩浆环境上，并了解较低温度(亚固相);< 600°C)工艺可以修改初级PGM组合。岩浆环境中铂族元素(PGE)的地球化学行为是高度亲铜的，而不是像预期的那样是高度亲铁的。这是因为大多数陆地岩浆系统是相对氧化的，比如……
{"title":"Petrogenesis of the Platinum-Group Minerals","authors":"B. O’Driscoll, J. González-Jiménez","doi":"10.2138/RMG.2016.81.09","DOIUrl":"https://doi.org/10.2138/RMG.2016.81.09","url":null,"abstract":"The platinum-group minerals (PGM) are a diverse group of minerals that concentrate the platinum-group elements (PGE; Os, Ir, Ru, Rh, Pt, and Pd). At the time of writing, the International Mineralogical Association database includes 135 named discrete PGM phases. Much of our knowledge of the variety and the distribution of these minerals in natural systems comes from ore deposits associated with mafic and ultramafic rocks and their derivatives (see also Barnes and Ripley 2016, this volume). Concentrations of PGM can be found in layered mafic–ultramafic intrusions. Although they don’t typically achieve ore grade status, supra-subduction zone upper mantle (preserved in ophiolite) lithologies (i.e., chromitite [> 60 vol.% Cr-spinel], pyroxenite) characteristically host a diversity of PGM assemblages as well (Becker and Dale 2016, this volume). Occurrences of the PGM in layered intrusions, ophiolites, and several other important settings will all be described in this review. In keeping with the general theme of this volume, the focus of this chapter is on relatively high-temperature (magmatic) settings. This is not a straightforward distinction to make, as PGM assemblages that begin as high-temperature parageneses may be modified at much lower temperatures during metamorphism, hydrothermal processes or surficial weathering (e.g., Hanley 2005). However, the vast majority of the published literature on PGM petrogenesis is based on occurrences from magmatic environments, an understandable bias given the importance of the major ore deposits that occur in some layered mafic–ultramafic intrusions, for example. For that reason, the emphasis of this review will be on high-temperature magmatic settings, with the understanding that lower temperature (sub-solidus; < 600 °C) processes can modify primary PGM assemblages. The geochemical behavior of the platinum-group elements (PGE) in magmatic settings is highly chalcophile and not, as might be expected, highly siderophile. This is because most terrestrial magmatic systems are relatively oxidized, such …","PeriodicalId":49624,"journal":{"name":"Reviews in Mineralogy & Geochemistry","volume":"67 1","pages":"489-578"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78346415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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