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Müllerite, the Fe-analogue of backite from Otto Mountain, California, USA Müllerite,来自美国加利福尼亚州奥托山的铁类似物
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-07-01 DOI: 10.3749/canmin.2000026
S. Mills, A. Kampf, K. Momma, R. Housley, J. Marty
Müllerite (IMA2019–060) is a new mineral found at several workings on Otto Mountain, 2.5 km NW of Baker, San Bernardino County, California, USA. Müllerite occurs as hexagonal tablets and thin plates up to 0.2 mm across, intergrown ball-like clusters, and scattered flakes. Crystals are yellow, tending to reddish-orange, and have a pale-yellow streak and subadamantine to greasy luster. Crystals are brittle with an irregular fracture and have a hardness of ∼2 and perfect cleavage on {001}. The main forms observed are {100} and {001}. The calculated density is 5.812 g/cm3. The empirical formula (based on 7 O + Cl + I apfu) is Pb1.83Ag0.26Fe0.93Al0.03Cu0.02Te6+0.95O5.56Cl1.30I0.14; the endmember formula is Pb2Fe3+(Te6+O6)Cl. Müllerite is trigonal, space group P312, with the unit cell parameters a = 5.2040(5), c = 8.9654(12) Å, V = 210.23(3) Å3, and Z = 1. The crystal structure of müllerite was refined using Rietveld analysis and converged to Rwp = 4.861%, S = 0.1873, RB = 1.800%, and RF = 0.691%. Müllerite is the Fe-analogue of backite, Pb2Al3+(Te6+O6)Cl.
Müllerite(IMA2019–060)是在美国加利福尼亚州圣贝纳迪诺县贝克西北2.5公里的奥托山的几个工作区发现的一种新矿物。Mülerite以直径达0.2毫米的六边形平板和薄板、共生球状星团和散射薄片的形式出现。晶体呈黄色,呈红橙色,有淡黄色条纹和亚大马士革至油腻的光泽。晶体很脆,有不规则的断裂,硬度为~2,在{001}上有完美的解理。观察到的主要形式是{100}和{001}。计算出的密度为5.812 g/cm3。经验公式(基于7O+Cl+I apfu)为Pb1.83Ag0.26Fe0.93Al0.03Cu0.02Te6+0.95O5.56Cl1.3OI0.14;端基分子式为Pb2Fe3+(Te6+O6)Cl。Müllerite是三角的,空间群P312,晶胞参数a=5.2040(5),c=8.9654(12)Å,V=210.23(3)Å3,Z=1。利用Rietveld分析对穆勒石的晶体结构进行了细化,其晶体结构收敛为Rwp=4.861%,S=0.1873,RB=1.800%,RF=0.691%。
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引用次数: 0
87 million years of recorded history in Labrador: Birth, life, and sleep of the Kiglapait Intrusion 拉布拉多8700万年的历史记录:Kiglapat入侵的出生、生活和睡眠
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-07-01 DOI: 10.3749/canmin.1900043
S. Morse, J. Brady, D. Banks
The Kiglapait Intrusion on the north coast of Labrador is a bowl-shaped body dominated by troctolite about 3500 km3 in initial volume and was created during an intrusive event perhaps lasting thousands of years. It was emplaced into anorthosite and metasedimentary rocks at an estimated roof depth of 9.6 km and a magma depth of 8.4 km; hence with a floor at 18 km depth. The primary magma for the intrusion is thought to have been of harzburgite composition; a large volume of olivine crystallized in transit, to the extent that the magma became saturated with plagioclase by the time it reached the site of emplacement or soon after. To test this hypothesis, piston-cylinder experiments were made at 5–15 kbar in graphite using the Kiglapait Intrusion bulk composition with Fo-rich olivine added. Results at 13 kbar yielded saturation with garnet, olivine, spinel, orthopyroxene, clinopyroxene, plagioclase, and melt. This assemblage is compatible with a lherzolite solidus at 1375 °C. A postulated harzburgite solidus at 15 kbar would be hotter, perhaps 1410 °C. Partial melt from this harzburgite rising into a hot, thinned lithosphere is presumed to have shed large amounts of olivine to produce the plagioclase-saturated troctolitic basal Lower Zone of the intrusion. Conditions of emplacement are schematically developed in ternary Al–Ca–Fe diagrams. Some high-pressure experimental compositions of clino- and orthopyroxene are metastably enriched in Al but do not affect the interpretation of the magmatic history. We show that olivine fractionation will pass through the compositions of these aluminous minerals to reach a relatively evolved saturation with only plagioclase and olivine, resulting in the voluminous Lower Zone of troctolite. The amount of olivine crystallized to reach this result is calculated, using multiphase Rayleigh fractionation and a standard MELTS routine, to between 30% and 50%. Previously published argon-argon mineral dates on hornblende, biotite, and feldspars have captured a cooling history from ∼1258 °C to the ambient ∼100 °C over the time interval 1307 to 1220 Ma, hence the 87 million year history claimed in the title.
位于拉布拉多北部海岸的Kiglapait岩体是一个碗状岩体,主要由橄榄岩组成,初始体积约为3500立方千米,是在一次可能持续数千年的侵入事件中形成的。其侵位于斜长岩和变质沉积岩中,顶板深度估计为9.6 km,岩浆深度估计为8.4 km;因此,海底深度为18公里。该侵入岩的原始岩浆被认为是由辉锌矿组成的;大量的橄榄石在运输过程中结晶,以至于岩浆在到达就位地点或之后不久就被斜长石饱和了。为了验证这一假设,使用添加富fo橄榄石的Kiglapait岩体组成,在5-15 kbar的石墨中进行了活塞缸实验。结果在13kbar下,石榴石、橄榄石、尖晶石、正辉石、斜辉石、斜长石和熔体饱和。该组合在1375°C时与沸石固体相容。假设的15kbar的黑锌矿固体会更热,可能是1410°C。据推测,从这个黑曜岩的部分熔体上升到一个热的、薄的岩石圈中,脱落了大量的橄榄石,形成了斜长石饱和的橄榄石基底侵入下部带。在三元Al-Ca-Fe图中图解地描述了放置条件。斜辉石和正辉石的高压实验成分在Al中亚稳富集,但不影响岩浆史的解释。橄榄石分选作用将穿过这些铝质矿物的组成,达到一个相对演化的饱和度,只有斜长石和橄榄石,形成体积较大的橄榄石下带。通过使用多相瑞利分馏和标准熔体程序,计算出达到该结果的橄榄石结晶量在30%到50%之间。先前发表的角闪石、黑云母和长石上的氩-氩矿物日期记录了1307至1220 Ma时间间隔内从~ 1258°C到环境~ 100°C的冷却历史,因此标题中声称的8700万年的历史。
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引用次数: 0
Sergevanite, Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O, a new eudialyte-group mineral from the Lovozero alkaline massif, Kola Peninsula Sergevanite,Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O,来自科拉半岛Lovozero碱性地块的一种新的真透析物族矿物
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-07-01 DOI: 10.3749/canmin.2000006
N. Chukanov, S. Aksenov, I. Pekov, D. Belakovskiy, S. A. Vozchikova, S. Britvin
The new eudialyte-group mineral sergevanite, ideally Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O, was discovered in highly agpaitic foyaite from the Karnasurt Mountain, Lovozero alkaline massif, Kola Peninsula, Russia. The associated minerals are microcline, albite, nepheline, arfvedsonite, aegirine, lamprophyllite, fluorapatite, steenstrupine-(Ce), ilmenite, and sphalerite. Sergevanite forms yellow to orange-yellow anhedral grains up to 1.5 mm across and the outer zones of some grains of associated eudialyte. Its luster is vitreous, and the streak is white. No cleavage is observed. The Mohs' hardness is 5. Density measured by equilibration in heavy liquids is 2.90(1) g/cm3. Calculated density is equal to 2.906 g/cm3. Sergevanite is nonpleochroic, optically uniaxial, positive, with ω = 1.604(2) and ε = 1.607(2) (λ = 589 nm). The infrared spectrum is given. The chemical composition of sergevanite is (wt.%; electron microprobe, H2O determined by HCN analysis): Na2O 13.69, K2O 1.40, CaO 7.66, La2O3 0.90, Ce2O3 1.41, Pr2O3 0.33, Nd2O3 0.64, Sm2O3 0.14, MnO 4.15, FeO 1.34, TiO2 1.19, ZrO2 10.67, HfO2 0.29, Nb2O5 1.63, SiO2 49.61, SO3 0.77, Cl 0.23, H2O 4.22, –O=Cl –0.05, total 100.22. The empirical formula (based on 25.5 Si atoms pfu, in accordance with structural data) is H14.46Na13.64K0.92Ca4.22Ce0.27La0.17Nd0.12Pr0.06Sm0.02Mn1.81Fe2+0.58Ti0.46Zr2.67Hf0.04Nb0.38Si25.5S0.30Cl0.20O81.35. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is trigonal, space group R3, with a = 14.2179(1) Å, c = 30.3492(3) Å, V = 5313.11(7) Å3, and Z = 3. In the structure of sergevanite, Ca and Mn are ordered in the six-membered ring of octahedra (at the sites M11 and M12), and Na dominates over Fe2+ at the M2 site. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 7.12 (70) (110), 5.711 (43) (202), 4.321 (72) (205), 3.806 (39) (033), 3.551 (39) (220, 027), 3.398 (39) (313), 2.978 (95) (), 2.855 (100) (404). Sergevanite is named after the Sergevan' River, which is near the discovery locality.
在俄罗斯科拉半岛Lovozero碱性地块Karnasurt山的高含银火山岩中发现了一种新的真透析物族矿物sergevanite,最好是Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O。伴生矿物有微斜长石、钠长石、霞石、arfvedsonite、aegirine、煌斑岩、氟磷灰石、钛铁矿-(Ce)、钛铁矿和闪锌矿。Sergevanite形成直径达1.5毫米的黄色至橙黄色的反角体颗粒,以及一些相关的真透析物颗粒的外部区域。它的光泽是玻璃状的,条纹是白色的。未观察到解理。莫氏硬度为5。通过在重质液体中平衡测量的密度为2.90(1)g/cm3。计算的密度等于2.906 g/cm3。Sergevanite是非相变的,光学单轴,正,ω=1.604(2)和ε=1.607(2)(λ=589 nm)。给出了红外光谱。硅镁石的化学成分为(wt.%;电子探针,通过HCN分析测定H2O):Na2O 13.69,K2O 1.40,CaO 7.66,La2O3 0.90,Ce2O3 1.41,Pr2O3 0.33,Nd2O3 0.64,Sm2O3 0.14,MnO 4.15,FeO 1.34,TiO2 1.19,ZrO2 10.67,HfO2 0.29,Nb2O5 1.63,SiO2 49.61,SO3 0.77,Cl 0.23,H2O 4.22,-O=Cl–0.05,总计100.22。经验公式(基于25.5个Si原子pfu,根据结构数据)为H14.46Na13.64K0.92Ca4.2Ce0.27La0.17Nd0.12Pr0.06Sm0.02Mn1.81Fe2+0.58Ti0.46Zr2.67Hf0.04Nb0.38Si25.5S0.30Cl0.20O81.35。使用单晶X射线衍射数据来确定晶体结构。新矿物是三角的,空间群R3,a=14.2179(1)Å,c=30.3492(3)Å、V=5531.11(7)Å3和Z=3。在sergevanite的结构中,Ca和Mn在八面体的六元环中(在位置M11和M12)是有序的,并且Na在M2位置上比Fe2+占主导地位。粉末X射线衍射图的最强谱线[d,Å(I,%)(hkl)]为:7.12(70)(110),5.711(43)(202),4.321(72)(205),3.806(39)(033),3.551(39),22027),3.398(39))(313),2.978(95)(),2.855(100)(404)。Sergevanite是以Sergevan河命名的,该河位于发现地附近。
{"title":"Sergevanite, Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O, a new eudialyte-group mineral from the Lovozero alkaline massif, Kola Peninsula","authors":"N. Chukanov, S. Aksenov, I. Pekov, D. Belakovskiy, S. A. Vozchikova, S. Britvin","doi":"10.3749/canmin.2000006","DOIUrl":"https://doi.org/10.3749/canmin.2000006","url":null,"abstract":"\u0000 The new eudialyte-group mineral sergevanite, ideally Na15(Ca3Mn3)(Na2Fe)Zr3Si26O72(OH)3·H2O, was discovered in highly agpaitic foyaite from the Karnasurt Mountain, Lovozero alkaline massif, Kola Peninsula, Russia. The associated minerals are microcline, albite, nepheline, arfvedsonite, aegirine, lamprophyllite, fluorapatite, steenstrupine-(Ce), ilmenite, and sphalerite. Sergevanite forms yellow to orange-yellow anhedral grains up to 1.5 mm across and the outer zones of some grains of associated eudialyte. Its luster is vitreous, and the streak is white. No cleavage is observed. The Mohs' hardness is 5. Density measured by equilibration in heavy liquids is 2.90(1) g/cm3. Calculated density is equal to 2.906 g/cm3. Sergevanite is nonpleochroic, optically uniaxial, positive, with ω = 1.604(2) and ε = 1.607(2) (λ = 589 nm). The infrared spectrum is given. The chemical composition of sergevanite is (wt.%; electron microprobe, H2O determined by HCN analysis): Na2O 13.69, K2O 1.40, CaO 7.66, La2O3 0.90, Ce2O3 1.41, Pr2O3 0.33, Nd2O3 0.64, Sm2O3 0.14, MnO 4.15, FeO 1.34, TiO2 1.19, ZrO2 10.67, HfO2 0.29, Nb2O5 1.63, SiO2 49.61, SO3 0.77, Cl 0.23, H2O 4.22, –O=Cl –0.05, total 100.22. The empirical formula (based on 25.5 Si atoms pfu, in accordance with structural data) is H14.46Na13.64K0.92Ca4.22Ce0.27La0.17Nd0.12Pr0.06Sm0.02Mn1.81Fe2+0.58Ti0.46Zr2.67Hf0.04Nb0.38Si25.5S0.30Cl0.20O81.35. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is trigonal, space group R3, with a = 14.2179(1) Å, c = 30.3492(3) Å, V = 5313.11(7) Å3, and Z = 3. In the structure of sergevanite, Ca and Mn are ordered in the six-membered ring of octahedra (at the sites M11 and M12), and Na dominates over Fe2+ at the M2 site. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 7.12 (70) (110), 5.711 (43) (202), 4.321 (72) (205), 3.806 (39) (033), 3.551 (39) (220, 027), 3.398 (39) (313), 2.978 (95) (), 2.855 (100) (404). Sergevanite is named after the Sergevan' River, which is near the discovery locality.","PeriodicalId":9455,"journal":{"name":"Canadian Mineralogist","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3749/canmin.2000006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49596749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 14
Mineral chemistry of gahnite from the Lalor metamorphosed VHMS deposit, Snow Lake, Manitoba 曼尼托巴雪湖Lalor变质VHMS矿床中菱铁矿的矿物化学特征
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-07-01 DOI: 10.3749/canmin.1900036
E. Wehrle, A. McDonald, D. Tinkham
Gahnite (ZnAl2O4) is a common accessory mineral at the Lalor auriferous Zn-Cu metamorphosed VHMS deposit (Snow Lake, Manitoba). To evaluate factors influencing its crystal chemistry, gahnite representing a range of textures, host mineral assemblages, and whole-rock compositions were analyzed for major, minor, and trace elements. The analyzed grains span the range of Ghn63-75Her15-22Spl10-18 and are un-zoned with respect to Zn, Fe, and Mg. A moderate positive correlation exists between Mg in gahnite and whole-rock MgO (R2 = 0.66). The minor- and trace-element chemistry of the Lalor gahnite is dominated by Mn (400–2600 ppm), Si (<25–250 ppm), and V (<25–2300 ppm). Based on the limited variability in gahnite major-element composition, as well as similar partitioning coefficients of Zn and Fe between sphalerite-gahnite pairs (indicating comparable metamorphic conditions of crystallization for the analyzed gahnite), metamorphic grade is interpreted to have had the strongest influence on gahnite major-element chemistry. Most sphalerite occurs with pyrite and pyrrhotite, an assemblage that would have buffered fS2 and fixed the Zn:Fe ratio in sphalerite, which also could have contributed to the narrow compositional range observed in gahnite. Magnesium was not an essential component of the sphalerite-consuming, gahnite-producing reactions, so its concentration in gahnite was more readily affected by whole-rock Mg. A small proportion of gahnite grains may have formed from the destabilization of silicates (staurolite and biotite), rather than sphalerite. These possible gahnite-forming reactions (sphalerite- versus biotite- or staurolite-consuming) appear to have had the strongest control on gahnite minor- and trace-element chemistry, as gahnite formed from sphalerite desulfidation reactions shows a range in Mn (450–2600 ppm) and restricted V/Mn values (<0.5), while gahnite interpreted to have formed from the dehydration of biotite and staurolite shows restricted Mn (<430 ppm) and a range of V/Mn values (0.75–5.5). Further work is recommended to investigate the possibility of using gahnite trace-element signatures (such as with Mn and V) to discriminate between gahnite that crystallized in sphalerite-rich and sphalerite-barren environments, as this concept has potential for application to exploration using detrital gahnite.
锌铝榴辉石(ZnAl2O4)是曼尼托巴雪湖Lalor含金锌铜变质VHMS矿床中常见的副矿物。为了评估影响其晶体化学的因素,研究人员分析了一系列结构、寄主矿物组合和整个岩石组成,包括主元素、微量元素和微量元素。所分析的晶粒分布在Ghn63-75Her15-22Spl10-18的范围内,锌、铁和镁的含量没有分区。镁元素与全岩MgO呈中等正相关(R2 = 0.66)。Lalor锌长晶石的微量元素和微量元素化学以Mn (400 ~ 2600 ppm)、Si (<25 ~ 250 ppm)和V (<25 ~ 2300 ppm)为主。基于锌矿主元素组成的有限变化,以及闪锌矿-锌矿对之间Zn和Fe的分配系数相似(表明所分析的锌矿的变质结晶条件相似),变质品位对锌矿主元素化学的影响最大。闪锌矿大多与黄铁矿和磁黄铁矿共生,这种组合可能缓冲了fS2,固定了闪锌矿中的Zn:Fe比值,这也可能导致闪锌矿的成分范围较窄。镁并不是消耗闪锌矿和产生锌锌矿反应的必需组分,因此镁在锌锌矿中的含量更容易受到全岩Mg的影响。一小部分辉长岩颗粒可能是由硅酸盐(橄榄石和黑云母)的失稳形成的,而不是闪锌矿。这些可能形成闪锌矿的反应(闪锌矿与黑云母或小沸石的消耗)似乎对闪锌矿的微量元素和微量元素化学具有最强的控制作用,因为闪锌矿脱硫反应形成的闪锌矿显示出Mn (450-2600 ppm)的范围和限制的V/Mn值(<0.5),而解释为由黑云母和小沸石脱水形成的闪锌矿显示出限制的Mn (<430 ppm)和V/Mn值(0.75-5.5)的范围。建议进一步研究利用闪锌矿微量元素特征(如Mn和V)来区分在富含闪锌矿和无闪锌矿环境中结晶的闪锌矿的可能性,因为这一概念有可能应用于利用碎屑闪锌矿进行勘探。
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引用次数: 1
Mineral chemistry and geochronology of the Rajasthan emerald deposits, NW India 印度西北部拉贾斯坦邦祖母绿矿床的矿物化学和地质年代学
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.1900055
P. Alexandre
The emerald deposits in Rajasthan, northwest India, are situated in a narrow NE–SW belt in the Aravalli Mountains. The studied deposits were formed by the metasomatic reaction between muscovite (± garnet ± tourmaline) pegmatites and lenticular bodies of altered ultramafic rocks that are hosted by the Delhi Group gneisses. This reaction produced phlogopite schists containing the exometasomatic emeralds, as in all other granite-related emerald deposits. Endometasomatic changes of the mineralogy of the pegmatites is indicated by the geochemistry of the muscovite (phengitic substitution) and the feldspars (disappearance of the potassic feldspar and calcification of the plagioclase). The K-Ar analyses of syngenetic phlogopite (from the phlogopite schist) and muscovite (from the pegmatites) give an age of ca. 790 Ma, close to that of the last major orogeny affecting the region. This is in accordance with the ages of other granite-related deposits, which all formed in conditions of active orogeny. The ages of the biotite are lower than those of the muscovite, indicating limited radiogenic argon loss as a result of deformation.
印度西北部拉贾斯坦邦的祖母绿矿床位于阿拉瓦利山脉的东北-西南狭窄地带。研究的矿床是由白云母(±石榴石±电气石)伟晶岩与德里群片麻岩所赋存的蚀变超镁铁质透镜体交代反应形成的。这个反应产生了含有外交代祖母绿的绿云母片岩,就像所有其他与花岗岩有关的祖母绿矿床一样。白云母(腐殖代用)和长石(钾长石消失,斜长石钙化)的地球化学特征表明伟晶岩的矿物学变化。同生的辉云母(来自辉云母片岩)和白云母(来自伟晶岩)的K-Ar分析显示其年龄约为790 Ma,接近影响该地区的最后一次主要造山运动的年龄。这与其他花岗岩相关矿床的年龄一致,均形成于活动造山条件下。黑云母的年龄比白云母的年龄低,表明由于变形造成的放射性氩损失有限。
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引用次数: 1
Adanite, a new lead-tellurite-sulfate mineral from the North Star mine, Tintic, Utah, and Tombstone, Arizona, USA Adanite,一种新的铅碲硫酸盐矿物,来自美国犹他州Tintic和亚利桑那州Tombstone的North Star矿
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.2000010
A. Kampf, R. Housley, G. Rossman, Hexiong Yang, R. Downs
Adanite, Pb₂ (Te⁴⁺O₃)(SO₄), is a new oxidation-zone mineral from the North Star mine, Tintic district, Juab County, Utah, and from Tombstone, Cochise County, Arizona, USA. The characterization of the species is based principally on North-Star holotype material. Crystals are beige wedge-shaped blades, up to about 1 mm in length, in cockscomb intergrowths. The mineral is transparent with adamantine luster, white streak, Mohs hardness 2½, brittle tenacity, conchoidal fracture, and no cleavage. The calculated density is 6.385 g/cm³. Adanite is biaxial (–), with α = 1.90(1), β = 2.04(calc), γ = 2.08(calc), 2V(meas) = 54(1)°. The Raman spectrum is consistent with the presence of tellurite and sulfate groups and the absence of OH and H₂O. Electron-microprobe analyses gave the empirical formula Pb_(1.89)Sb³⁺_(0.02)Te⁴⁺_(0.98)S⁶⁺_(1.04)Cl_(0.02)O_(6.98). The mineral is monoclinic, space group P2₁/n, with a = 7.3830(3), b = 10.7545(5), c = 9.3517(7) A, β = 111.500(8)°, V = 690.86(7) A₃, and Z = 4. The four strongest X-ray powder diffraction lines are [dobs A(I)(hkl)]: 6.744(47)⁠, 3.454(80)⁠, 3.301(100)⁠, and 3.048(73)⁠. The structure (R₁ = 0.022 for 1906 I > 2σI reflections) contains Te⁴⁺O₃ pyramids that are joined by short (strong) Pb–O bonds to form sheets. Interlayer SO₄ groups link the sheets via long Pb–O and Te–O bonds.
Adanite, Pb₂(Te⁴⁺O₃)(SO₄)是一种新的氧化带矿物,来自犹他州Juab县Tintic区North Star矿和美国亚利桑那州Cochise县Tombstone矿。该物种的特征主要基于北星全模材料。晶体是米黄色的楔形叶片,长度可达1毫米左右,在鸡冠状丛生物中。该矿物透明,具有金刚光泽,白色条纹,莫氏硬度2½,脆韧性,贝壳状断裂,无解理。计算密度为6.385 g/cm³。Adanite双轴(-),α= 1.90(1),β= 2.04(钙)、γ= 2.08(钙),2 v(量)= 54(1)°。拉曼光谱与碲和硫酸盐基团的存在一致,没有OH和h2o。电子探针分析给出了实验式Pb_(1.89)Sb³⁺_(0.02)Te⁴⁺_(0.98)S 26⁺_(1.04)Cl_(0.02)O_(6.98)。该矿物为单斜型,空间群为P2₁/n, a = 7.3830(3), b = 10.7545(5), c = 9.3517(7) a, β = 111.500(8)°,V = 690.86(7) a₃,Z = 4。四条最强的x射线粉末衍射线为[dobs A(I)(hkl)]: 6.744(47)、3.454(80)、3.301(100)和3.048(73)。该结构(对于1906 I > 2σI反射,R₁= 0.022)包含Te⁴⁺O₃金字塔,这些金字塔由短(强)Pb-O键连接成薄片。层间的SO₄基团通过长Pb-O和Te-O键连接薄片。
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引用次数: 4
High-resolution LA-ICP-MS trace-element mapping of magmatic biotite: A new approach for studying syn- to post-magmatic evolution 岩浆黑云母的高分辨率LA-ICP-MS微量元素填图:研究岩浆前后演化的新方法
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.1900101
Z. Azadbakht, D. Lentz
Biotite grains from 22 felsic intrusions in New Brunswick were mapped in situ using a laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS). We investigated the extent to which biotite can retain its magmatic zoning patterns and, where zoning does exist, how it can be used to elucidate early to late stage, syn-magmatic to post-crystallization processes. Although the major element and halogen contents of the examined biotite phenocrysts are homogeneous, two-thirds of the grains display trace-element zoning for Ba, Rb, and Cs. The results also indicated that zoning is better retained in larger grains (i.e., > 500 × 500 μm) with minimal alteration and mineral inclusions. An exceptionally well-zoned Li-rich siderophyllite from the Pleasant Ridge topaz granite in southwestern New Brunswick shows Ti, Ta, Sn, W, Cs, Rb, and V (without Li or Ba) zoning. Cesium values increase from 200 to 1400 ppm from core to rim. Conversely, Sn and W values decrease toward the rim (50 to 10 and 100 to 10 ppm, respectively). Tantalum and Ti values show fewer variations but drop abruptly close to the rim of the grain (100 to 20 and 2000 to 500 ppm, respectively). These observations may indicate crystallization of mineral phases with high partition coefficients for these highly incompatible elements (except Ti) (e.g., cassiterite and rutile) followed by fractionation of a fluid phase at a later stage of magma crystallization. The preservation of zoning may indicate rapid cooling post-crystallization of the parent magma.
使用激光烧蚀电感耦合等离子体质谱仪(LA-ICP-MS)对新不伦瑞克省22个长英质侵入体的黑云母颗粒进行了原位测绘。我们研究了黑云母在多大程度上可以保留其岩浆分带模式,以及在确实存在分带的情况下,如何使用它来阐明早期到晚期、同岩浆到结晶后的过程。尽管所检查的黑云母斑晶的主要元素和卤素含量是均匀的,但三分之二的晶粒显示出Ba、Rb和Cs的微量元素分带。结果还表明,在蚀变和矿物包裹体最小的情况下,较大晶粒(即>500×500μm)中更好地保留了分带。新不伦瑞克省西南部Pleasant Ridge黄玉花岗岩中一种分区异常好的富锂菱铁矿显示出Ti、Ta、Sn、W、Cs、Rb和V(不含Li或Ba)分区。铯的含量从200 ppm增加到1400 ppm。相反地,Sn和W值朝着边缘减小(分别为50至10和100至10ppm)。钽和钛的值变化较小,但在晶粒边缘附近突然下降(分别为100至20和2000至500ppm)。这些观察结果可能表明,对于这些高度不相容的元素(Ti除外)(例如锡石和金红石),具有高分配系数的矿物相结晶,然后在岩浆结晶的后期阶段分馏液相。分区的保存可能表明母岩浆结晶后迅速冷却。
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引用次数: 9
Badakhshanite-(Y), Y2Mn4Al(Si2B7BeO24), a new mineral species of the perettiite group from a granite miarolic pegmatite in Eastern Pamir, the Gorno Badakhshan Autonomous Oblast, Tajikistan Badakhshanite-(Y), Y2Mn4Al(Si2B7BeO24),来自塔吉克斯坦戈尔诺-巴达赫尚自治州东帕米尔高原花岗岩镁铁伟晶岩的一种新矿物
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.2000003
L. Pautov, M. A. Mirakov, F. Cámara, E. Sokolova, F. Hawthorne, Manuchekhr A. Schodibekov, V. Y. Karpenko
Badakhshanite-(Y), ideally Y2Mn4Al(Si2B7BeO24), is a tetrahedral sheet-structure mineral found in the Dorozhny (Road) miarolitic granitic pegmatite within the Kukurt pegmatite field 45 km E of Murghab, Eastern Pamir, Gorno-Badakhshan Autonomous Oblast, Tajikistan. Badakhshanite-(Y) occurs in medium- to coarse-grained non-graphic albite-microcline-quartz pegmatites in close association with smoky quartz, Sc-bearing spessartine, Sc-bearing tusionite, and schorl. It often grows together with Sc-bearing tusionite and occurs as single columnar crystals ranging from 50 to 400 μm in length, as inclusions in spessartine and tourmaline, and rarely as crystals in blebs along boundaries between garnet, tourmaline, and quartz. Badakhshanite-(Y) is yellow brown and has a white streak and a vitreous luster. It is brittle, with a conchoidal fracture, Mohs hardness of 6.5–7, and calculated density of 4.41 g/cm. In thin section it is transparent and pale yellow, non-pleochroic, biaxial (–), with α = 1.805(2), βcalc = 1.827, γ = 1.835(3) (λ = 590 nm); 2V (meas.) = –60(10)°. Dispersion is weak, r > v. Extinction is straight, elongation is negative. FTIR spectra show the absence of (OH) and H2O groups. Chemical analysis by electron microprobe using WDS (6 points), SIMS, and ICP-OES for B and Be gave SiO2 11.96, ThO2 0.12, Sm2O3 0.17, Gd2O3 0.30, Tb2O3 0.10, Dy2O3 0.73, Ho2O3 0.19, Er2O3 1.34, Tm2O3 0.54, Yb2O3 8.82, Lu2O3 2.32, Y2O3 16.60, Sc2O3 1.57, Al2O3 3.06, B2O3 22.06, FeO 0.94, MnO 23.33, CaO 0.58, BeO 2.84, total 97.57 wt.%.The empirical formula based on 24 O apfu is (Y1.21REE0.78Th0.01)Σ2(Mn3.47Y0.34Ca0.11Fe2+0.08)Σ4(Al0.63Sc0.24Fe2+0.06□0.07)Σ1[(Si2.10B6.69Be1.20)Σ9.99O24], where REE = (Yb0.47Lu0.12Dy0.04Er0.07Tm0.03 Ho0.01Gd0.02Sm0.01Tb0.01)Σ0.78. Badakhshanite-(Y) is orthorhombic, space group Pnma, a 12.852(1), b 4.5848(5), c 12.8539(8) Å, V 757.38(7) Å3, Z = 2. The crystal structure was refined to R1 = 4.31% based on 1431 unique [F > 4σF] reflections. In the crystal structure of badakhshanite-(Y), a layer of tetrahedra parallel to (010) is composed of four different tetrahedrally coordinated sites: Si, B(1), B(2), and T ( = 1.623 Å, = 1.485 Å, = 1.479 Å, = 1.557 Å), which form four-, five-, and eight-membered rings, having the composition (Si2B7BeO24). Between the sheets of tetrahedra, there are three cation sites: M(1), M(2), and M(3) ( = 2.346 Å, = 2.356 Å, = 2.016 Å) occupied by Y(REE), Mn2+(Y, Ca, Fe2+), and Al(Sc), respectively. The M(1,2) sites ideally give Y2Mn4apfu; the M(3) site ideally gives Al apfu. Badakhshanite-(Y) is an Al- and Be-analogue of perettiite-(Y).
巴达赫尚岩-(Y),理想情况下为Y2Mn4Al(Si2B7BeO24),是一种四面体片状结构矿物,发现于塔吉克斯坦戈尔诺·巴达赫尚自治州帕米尔东部Murghab以东45 km的Kukurt伟晶岩区内的Dorozhny(公路)泥质花岗伟晶岩中。Badakhshanite-(Y)产于中粗粒非图形钠长石-微斜长石英伟晶岩中,与烟石英、含Sc的锡锡矿、含Sc-的硫铁矿和硫铁密切相关。它通常与含Sc的锂辉石一起生长,以50至400μm长的单柱状晶体的形式出现,在锂辉石和电气石中作为包裹体出现,很少在石榴石、电气石和石英之间的边界处作为气泡中的晶体出现。Badakhshanite-(Y)为黄棕色,具有白色条纹和玻璃光泽。它是脆性的,具有贝壳状断裂,莫氏硬度为6.5–7,计算密度为4.41 g/cm。在薄切片中,它是透明的浅黄色,非多色的,双轴(–),α=1.805(2),βcalc=1.827,γ=1.835(3)(λ=590nm);2V(测量值)=–60(10)°。色散较弱,r>v。消光是直的,伸长率是负的。FTIR光谱显示不存在(OH)和H2O基团。使用WDS(6点)、SIMS和ICP-OES对B和Be进行电子探针化学分析,得到SiO2 11.96、ThO2 0.12、Sm2O3 0.17、Gd2O3 0.30、Tb2O3 0.10、Dy2O3 0.73、Ho2O3 0.19、Er2O3 1.34、Tm2O3 0.54、Yb2O3 8.82、Lu2O3 2.32、Y2O3 16.60、Sc2O3 1.57、Al2O3 3.06、B2O3 22.06、FeO 0.94、MnO 23.33、CaO 0.58、BeO 2.84,基于24O apfu的经验公式为(Y1.21REE0.78Th0.01)∑2(Mn3.47Y0.34Ca0.11Fe2+0.08)∑4(Al0.63Sc0.24Fe2+0.06□0.07)∑1[(Si2.10B6.69Be1.20)∑9.99O24],其中REE=(Yb0.47Lu0.12Dy0.04Er0.07Tm0.03Ho0.01Gd0.02Sm0.01Tb0.01)∑0.78。Badakhshanite-(Y)是正交的,空间群Pnma,a 12.852(1),b 4.5848(5),c 12.8539(8)Å,V 757.38(7)Å3,Z=2。基于1431次独特的[F>4σF]反射,晶体结构被细化为R1=4.31%。在badakhshanite-(Y)的晶体结构中,平行于(010)的四面体层由四个不同的四面体配位位点组成:Si、B(1)、B(2)和T(=1.623Å,=1.485Å,1.479Å,1.557Å),它们形成四元、五元和八元环,组成为(Si2B7BeO24)。在四面体片之间,有三个阳离子位点:M(1)、M(2)和M(3)(=2.346Å,=2.356Å,=20.016Å)分别被Y(REE)、Mn2+(Y、Ca、Fe2+)和Al(Sc)占据。M(1,2)位理想地给出Y2Mn4apfu;M(3)位点理想地给出Al apfu。Badakhshanite-(Y)是一种铝和铍的类似物。
{"title":"Badakhshanite-(Y), Y2Mn4Al(Si2B7BeO24), a new mineral species of the perettiite group from a granite miarolic pegmatite in Eastern Pamir, the Gorno Badakhshan Autonomous Oblast, Tajikistan","authors":"L. Pautov, M. A. Mirakov, F. Cámara, E. Sokolova, F. Hawthorne, Manuchekhr A. Schodibekov, V. Y. Karpenko","doi":"10.3749/canmin.2000003","DOIUrl":"https://doi.org/10.3749/canmin.2000003","url":null,"abstract":"\u0000 Badakhshanite-(Y), ideally Y2Mn4Al(Si2B7BeO24), is a tetrahedral sheet-structure mineral found in the Dorozhny (Road) miarolitic granitic pegmatite within the Kukurt pegmatite field 45 km E of Murghab, Eastern Pamir, Gorno-Badakhshan Autonomous Oblast, Tajikistan. Badakhshanite-(Y) occurs in medium- to coarse-grained non-graphic albite-microcline-quartz pegmatites in close association with smoky quartz, Sc-bearing spessartine, Sc-bearing tusionite, and schorl. It often grows together with Sc-bearing tusionite and occurs as single columnar crystals ranging from 50 to 400 μm in length, as inclusions in spessartine and tourmaline, and rarely as crystals in blebs along boundaries between garnet, tourmaline, and quartz. Badakhshanite-(Y) is yellow brown and has a white streak and a vitreous luster. It is brittle, with a conchoidal fracture, Mohs hardness of 6.5–7, and calculated density of 4.41 g/cm. In thin section it is transparent and pale yellow, non-pleochroic, biaxial (–), with α = 1.805(2), βcalc = 1.827, γ = 1.835(3) (λ = 590 nm); 2V (meas.) = –60(10)°. Dispersion is weak, r > v. Extinction is straight, elongation is negative. FTIR spectra show the absence of (OH) and H2O groups. Chemical analysis by electron microprobe using WDS (6 points), SIMS, and ICP-OES for B and Be gave SiO2 11.96, ThO2 0.12, Sm2O3 0.17, Gd2O3 0.30, Tb2O3 0.10, Dy2O3 0.73, Ho2O3 0.19, Er2O3 1.34, Tm2O3 0.54, Yb2O3 8.82, Lu2O3 2.32, Y2O3 16.60, Sc2O3 1.57, Al2O3 3.06, B2O3 22.06, FeO 0.94, MnO 23.33, CaO 0.58, BeO 2.84, total 97.57 wt.%.The empirical formula based on 24 O apfu is (Y1.21REE0.78Th0.01)Σ2(Mn3.47Y0.34Ca0.11Fe2+0.08)Σ4(Al0.63Sc0.24Fe2+0.06□0.07)Σ1[(Si2.10B6.69Be1.20)Σ9.99O24], where REE = (Yb0.47Lu0.12Dy0.04Er0.07Tm0.03 Ho0.01Gd0.02Sm0.01Tb0.01)Σ0.78. Badakhshanite-(Y) is orthorhombic, space group Pnma, a 12.852(1), b 4.5848(5), c 12.8539(8) Å, V 757.38(7) Å3, Z = 2. The crystal structure was refined to R1 = 4.31% based on 1431 unique [F > 4σF] reflections. In the crystal structure of badakhshanite-(Y), a layer of tetrahedra parallel to (010) is composed of four different tetrahedrally coordinated sites: Si, B(1), B(2), and T (<Si–O> = 1.623 Å, <B(1)–O> = 1.485 Å, <B(2)–O> = 1.479 Å, <T–O> = 1.557 Å), which form four-, five-, and eight-membered rings, having the composition (Si2B7BeO24). Between the sheets of tetrahedra, there are three cation sites: M(1), M(2), and M(3) (<M(1)–O> = 2.346 Å, <M(2)–O> = 2.356 Å, <M(3)–O> = 2.016 Å) occupied by Y(REE), Mn2+(Y, Ca, Fe2+), and Al(Sc), respectively. The M(1,2) sites ideally give Y2Mn4apfu; the M(3) site ideally gives Al apfu. Badakhshanite-(Y) is an Al- and Be-analogue of perettiite-(Y).","PeriodicalId":9455,"journal":{"name":"Canadian Mineralogist","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3749/canmin.2000003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41308869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Geochemistry of the chromitite stringer at the contact of the mafic sequence and the ultramafic sequence in the Unki Mine area, Shurugwi Subchamber of the Great Dyke, Zimbabwe 津巴布韦Great Dyke Shurugwi Subchaber Unki矿区镁铁质序列和超镁铁质序列接触处铬铁矿细脉的地球化学
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.1900052
J. Chaumba, C. Musa
Several models have been proposed to explain the origin of a chromitite stringer located at the contact between the Mafic and Ultramafic Sequences in the Unki Mine area of the Shurugwi Subchamber of the Great Dyke, Zimbabwe. A petrographic and geochemical study of this chromitite stringer was undertaken with the aim of constraining its origin. Forty-three chromite compositions were obtained from the studied chromitite stringer, which is characterized by a chromium number between 59.9 and 62.8 and a magnesium number which ranges from 37.8 to 46.4. The chromites at the contact zone in the Unki Mine commonly contains inclusions of sulfides, orthopyroxene, plagioclase, and/or amphiboles. The chromites likely formed early in the crystallization history of the Mafic Sequence, as they are commonly partially rimmed by sulfides and they occur as inclusions in plagioclase crystals. Unlike chromites from underlying Ultramafic Sequence chromitite layers, chromites at the contact zone contain low Cr2O3 contents which range from 39.4 to 42.6 wt.%. Furthermore, these chromites are enriched in Fe compared to most Great Dyke chromitites, which is interpreted to be a consequence of subsolidus exchange of Mg into orthopyroxene and Fe into the chromite. The absence of zoning in the chromites at this contact zone, and their low Mn, Fe contents, is consistent with attainment of equilibrium because the altered chromites often contain Cr-bearing magnetite rims. Two possible models for the formation of this chromitite stringer are mixing of relatively primitive and evolved magmas (i.e., ultramafic and anorthositic magma), possibly of different oxygen fugacities, and chemical diffusion across the contact between the Mafic and the Ultramafic sequences which resulted in melting at and below this boundary. The latter would have caused preferential loss of orthopyroxene from the underlying P1 Pyroxenite Layer, accompanied by re-precipitation of chromite at this contact.
人们提出了几种模型来解释位于津巴布韦大堤Shurugwi亚室Unki矿区基岩和超基岩层序接触处的铬铁矿条带的起源。对该铬铁矿细带进行了岩石学和地球化学研究,以确定其成因。从所研究的铬铁矿串中得到43种铬铁矿组成,其铬值为59.9 ~ 62.8,镁值为37.8 ~ 46.4。温基矿接触带铬铁矿通常含有硫化物、正辉石、斜长石和/或角闪石包裹体。铬铁矿可能形成于镁铁质层序结晶史的早期,它们通常部分被硫化物包围,并以包裹体的形式出现在斜长石晶体中。与下伏超镁基层序铬铁矿不同,接触带铬铁矿的Cr2O3含量较低,为39.4% ~ 42.6 wt.%。此外,与大多数大堤铬铁矿相比,这些铬铁矿富含铁,这被解释为镁转化为正辉石和铁转化为铬铁矿的亚固体交换的结果。该接触带铬铁矿没有分带,且锰、铁含量较低,与蚀变铬铁矿通常含有含铬磁铁矿边缘,从而达到平衡相一致。这一铬铁矿条纹形成的两种可能的模式是相对原始和演化的岩浆(即超镁铁质岩浆和斜长岩岩浆)的混合,可能具有不同的氧逸度,以及化学扩散穿过镁铁质和超镁铁质层序之间的接触,导致在这一边界处和以下熔化。后者可能导致下伏的P1辉石层中正辉石的优先损失,并伴随着铬铁矿在此接触处的再沉淀。
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引用次数: 2
Carbonate-bearing phosphohedyphane–“Hydroxylphosphohedyphane” and cerussite: Supergene products of galena alteration in Permian aplite (Western Carpathians, Slovakia) 含碳酸盐的磷hedyphane——“羟基磷hedyphine”和铈矿:二叠纪细晶岩中方铅矿蚀变的浅生产物(斯洛伐克喀尔巴阡山西部)
IF 0.9 4区 地球科学 Q3 Earth and Planetary Sciences Pub Date : 2020-05-01 DOI: 10.3749/canmin.1900082
M. Ondrejka, P. Bačík, M. Putiš, P. Uher, T. Mikuš, J. Luptáková, Š. Ferenc, A. Smirnov
A unique assemblage of hedyphane-group minerals of the apatite supergroup associated with galena, cerussite, and calcite occurs in a Permian aplite dike crosscutting orthogneisses belonging to the pre-Alpine basement of the Veĺký Zelený Potok Valley in the Veporic Unit, Western Carpathians, Central Slovakia. The secondary Ca-Pb phosphates include phosphohedyphane Ca2Pb3(PO4)3Cl and (OH)-dominant “hydroxylphosphohedyphane” Ca2Pb3(PO4)3OH. Detailed EPMA and Raman spectroscopy of the hedyphane-group minerals reveal the presence of Pb, Ca, P, and Cl as major constituents; the systematic presence of (CO3)2– (up to 2.6 wt.% CO2calc; 0.65 apfu C) substituting for (PO4)3– (B-type) is the first reported carbonate-bearing phosphohedyphane in nature. There is also significant localized halogen deficiency (0.38–0.49 apfu Cl+F) which suggests the potential for a new mineral, “hydroxylphosphohedyphane”. The secondary assemblage described herein results from very low-temperature sulfide-carbonate reactions and further near-surface supergene alteration of primary magmatic or metamorphic phosphate minerals (mainly apatite) and hydrothermal galena in the alkaline CO2-rich groundwater.
与方铅矿、铈矿和方解石相关的磷灰石超群的hedyphane族矿物的独特组合出现在二叠纪细晶岩脉中,该细晶岩岩脉横切正片麻岩,属于斯洛伐克中部喀尔巴阡山脉西部Veporic单元的VeýkýZelenýPotok山谷的前阿尔卑斯基底。次生Ca-Pb磷酸盐包括磷酸hedyphane Ca2Pb3(PO4)3Cl和(OH)占主导地位的“羟基膦基膦”Ca2Pb3(PO3)3OH。hedyphane族矿物的详细EPMA和拉曼光谱揭示了Pb、Ca、P和Cl作为主要成分的存在;系统存在的(CO3)2-(高达2.6 wt.%CO2calc;0.65 apfu C)取代(PO4)3-(B型)是自然界中第一个报道的含碳酸盐的磷杂环乙烷。此外,还存在显著的局部卤素缺乏症(0.38–0.49 apfu Cl+F),这表明存在一种新矿物“羟基膦酸”的潜力。本文所述的次生组合是由非常低温的硫化物-碳酸盐反应以及碱性富CO2地下水中原生岩浆或变质磷酸盐矿物(主要是磷灰石)和热液方铅矿的进一步近地表浅生蚀变引起的。
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引用次数: 2
期刊
Canadian Mineralogist
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