Reply to discussion by RN Scoon and AA Mitchell on the paper “The Bushveld complex,South Africa: formation of platinum-palladium,chrome and vanadium-rich layers via hydrodynamic sorting of a mobilized cumulate slurry in a large,relatively slowly cooling,subsiding magma chamber” by WD Maier,S-J Barnes,and DI Groves     

Wolfgang D. Maier  Sarah-Jane Barnes  David I. Groves 《Mineralium Deposita》2014,49(3):405-407

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Preface – Special Issue: Carbonatites and associated mineralization     

D. I. Groves  L. G. Gwalani 《Mineralogy and Petrology》2004,80(3-4):123-126

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The Phalabowra (Palabora) carbonatite-hosted magnetite–copper sulfide deposit, South Africa: an end-member of the iron-oxide copper–gold–rare earth element deposit group?     

David I. Groves  Noreen M. Vielreicher 《Mineralium Deposita》2001,36(2):189-194

Olympic Dam-type iron-oxide copper–gold deposits are widely recognised in terrains with significant Palaeoproterozoic to Mesoproterozoic granitic magmatism. Most researchers favour a magmatic association for these deposits, but none of the 100–2000 Mt recognised copper-bearing deposits has a spatial and/or temporal relationship to an intrusive body of sufficient dimensions to produce the hosting giant breccia and/or hydrothermal systems. In other words, if the recognised ore-bodies are magmatic-hydrothermal, they must be classified as distal deposits. The magnetite–copper–phosphate–rare earth element pipe-like carbonatite-hosted orebody at Loolekop, within the larger Phalabowra Carbonatite Complex, has many features to suggest that it represents an end member of the Olympic Dam-type deposit class hosted within its magmatic source rock. It (1) falls broadly within the appropriate age range, (2) has a similar giant size and low copper grade, (3) is dominated by magnetite, (4) has sulfur-poor copper-sulfide minerals and lacks iron sulfides, (5) is silica-poor, and (6) is enriched in REE, particularly LREE, as well as P, F, U and Th. As an end member of the Olympic Dam-type deposits, the Loolekop orebody can help explain the common siting of the deposits at craton edges or other lithospheric boundaries, where decompression melting of metasomatised mantle can produce volatile-rich alkaline melts (rich in REE, P, F, etc.). Such melts are capable of generating sulfur-deficient volatiles enriched in copper and gold, among other elements, as well as phreatic breccia pipes and associated intense metasomatism, the most common features of the Olympic Dam-type deposits. Received: 27 July 2000 / Accepted: 2 October 2000  相似文献   

冀东峪耳崖和牛心山花岗岩体SHRIMP锆石U-Pb定年及其意义   总被引：18，自引：0，他引：18  

罗镇宽  裘有守  关康  苗来成  Y.M.Qiu  N.J.McNaughton  D.I.Groves 《矿物岩石地球化学通报》2001,20(4):278-285

侵入冀东马兰峪复背斜的前寒武岩层中的花岗岩体与区内金矿床有密切的空间关系 ,但成岩时代有争议 ,与金矿床的成因关系不明。本文采用SHRIMP定年方法对含有金矿床的峪耳岩和牛心山岩体进行了锆石U Pb年龄测定 ,获峪耳崖岩体灰白色花岗岩的2 0 6Pb 2 3 8U年龄 175± 1Ma ,肉红色花岗岩的年龄为 174± 3Ma ;牛心山花岗岩的年龄为 172± 2Ma。这 3个年龄在误差范围内可看成是同时代的产物 ,属中生代燕山期。这组年龄限定了金矿化年龄的下限 ,表明金矿化发生在中生代燕山中期后 ,但并不能精确厘定金矿化的年龄 ,因为花岗岩侵入后 ,金矿化之前 ,还有脉岩侵入 ,金矿化与花岗岩本身并无直接的成因关系。  相似文献   

Geological setting and mineralization model for the Cleo gold deposit, Eastern Goldfields Province, Western Australia   总被引：1，自引：0，他引：1  

Suzanne M. Brown  David I. Groves  Philip G. Newton 《Mineralium Deposita》2002,37(8):704-721

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辽宁凌源柏杖子金矿区花岗岩SHRIMP锆石U-Pb年龄   总被引：6，自引：0，他引：6  

罗镇宽  李俊建  关康  裘有守  Y.M.Qiu  N.J.McNaughton  D.I.Groves 《华北地质》2004,27(2):82-85,128

采用SHRIMP测年方法测得柏杖子金矿区含矿花岗岩的锆石U-Pb年龄为(222±3)Ma,与区内都山花岗岩基和三家子金矿区花岗斑岩的年龄一致,属中生代印支期后碰撞花岗岩。该年龄限定了金矿化年龄的下限,即金矿化不可能早于印支期,但并不能确定金矿化的精确年龄。根据金矿脉与后期岩脉伴生的特征,矿化可能发生在中生代燕山期。  相似文献   

Zircon Senstive High Resolution Ion Microprobe (SHRIMP) study of granitoid intrusions in Zhaoye Gold Belt of Shandong Province and its implication   总被引：1，自引：0，他引：1  

Laicheng Miao  Zhenkuan Luo  Jiazhan Huang  Kang Guan  G. L. Wang  J. N. Mcnaughton  I. D. Groves 《中国科学D辑(英文版)》1997,40(4):361-369

The zircon Sensitive High Resolution Ion Microprobe (SHRIMP) results show that granitoid intrusions in Zhaoye Gold Belt were emplaced at two periods of Mesozoic: Linglong and Luanjiahe types of granitic intrusions were emplaced between 160 Ma and 150 Ma (late Jurassic); Guojialing type of granodioritic intrusions, 130 Ma and 126 Ma (early Cretaceous). All the three types contain at least two major generations of inherited zircons with Precambrian (>650 Ma) and early Mesozoic ages (200–250 Ma), respectively. The former suggests that these plutonic rocks are of crustal origin and that Precambrian basement with component of sialic crust up to 3.4 Ga old (Middle Archean) exists in the region. The presence of abundant inherited zircons with early Mesozoic age indicates that the Precambrian basement was affected by a major tectono-thermal event, that is the collision of the North and South China blocks, at 250 Ma to 200 Ma. SHRIMP results also indicate that the gold mineralization in the region took place between 126 Ma and 120 Ma. Project supported by the Sino-Australian Economic and Technical Fund.  相似文献   

Syn-amphibolite facies archaean lode gold mineralisation in the Mt. York District,Pilbara Block,Western Australia     

P. Neumaryr  D. I. Groves  J. R. Ridley  C. D. Koning 《Mineralium Deposita》1993,28(6):457-468

The Archaean lode gold deposits in the Mt. York District, Pilbara Block, Western Australia are hosted in banded iron formation (Main Hill/Breccia Hill prospect) of the ca. 3.33 Ga Gorge Creek Group and in amphibolites (Zakanaka prospect) of the ca. 3.46 Ga Warrawoona Group. Gold mineralisation at the Main Hill/Breccia Hill prospect is associated with breccias comprising quartz clasts in a quartz-pyrrhotite matrix, and quartz-amphibole veins, with löllingite being the major host for gold. Minimum temperatures for gold mineralisation at the prospect are constrained as 455°C to 550°C by arsenopyrite thermometry. Gold mineralisation at the Zakanaka prospect is spatially associated with quartzclinopyroxene-calcite-microcline-calcic-amphibole veins and biotite altered wallrock adjacent to the veins. Temperatures for vein emplacement are estimated as 480°C to 570°C using both plagioclase-amphibole thermometry and mineral equilibria with respect to T and X_CO2. The timing of gold mineralisation relative to the peak of metamorphism is constrained by mineral textures and the relative temperatures of hydrothermal alteration and metamorphism. Gold mineralisation at both deposits was broadly synchronous with the peak of regional amphibolite facies metamorphism, which reached temperatures of 520°C to 640°C based on amphibole-plagioclase and garnet-biotite thermometry. In this respect, the deposits are similar to other well documented syn-amphibolite facies lode gold deposits from the Archaean Southern Cross greenstone belt in the Yilgarn Block, and represent the deeper section of a crustal continuum of lode gold deposits that includes mesothermal deposits such as those at Kalgoorlie at higher crustal levels.  相似文献   

The Granny Smith gold deposit: the role of heterogeneous stress distribution at an irregular granitoid contact in a greenschist facies terrane     

V. J. Ojala  J. R. Ridley  D. I. Groves  G. C. Hall 《Mineralium Deposita》1993,28(6):409-419

The Granny Smith gold deposits formed late in the structural history of the Yilgarn Block at a high crustal level in a largely brittle structural régime. Gold mineralisation is located along a N-S striking fault which wraps around the contact of a small granitoid intrusion. In different sections of the fault, mineralisation may be developed in the granitoid, in the adjacent sedimentary sequence and/or along the contact between them. In the granitoid, gold mineralisation is in conjugate networks of thin carbonate-quartz veins and their alteration halos. Small displacements along veins are common. In contrast, veins and faults in the sedimentary rocks are subparallel to bedding. Spatial variations in the conjugate vein orientations indicate that the local stress field was heterogeneous and controlled by the shape of the granitoid contact. The greatest variations in vein and implied stress orientations occur in zones where the contact is most irregular. These are also the areas of richest mineralisation. Fluid flow was thus focused in a regional-scale low mean-stress region created by the geometry of the granitoid intrusion. Its irregular contact caused deposit scale variations in fluid flow and resulted in heterogeneous gold grades along the contact zone.  相似文献   

A 3500 Ma plutonic and volcanic calc-alkaline province in the Archaean East Pilbara Block     

M. J. Bickle  L. F. Bettenay  M. E. Barley  H. J. Chapman  D. I. Groves  I. H. Campbell  J. R. de Laeter 《Contributions to Mineralogy and Petrology》1983,84(1):25-35

Variably foliated, predominantly granodioritic plutonic rocks from the northern part of the Shaw Batholith in the east Pilbara Archaean craton are dated at 3,499±22 Ma (2σ errors) by a whole-rock Pb-Pb isochron. These rocks intrude the surrounding greenstone sequence, and their age is indistinguishable from that sequence. High strain grey gneisses which occupy much of the western and southern Shaw Batholith are chemically and isotopically similar to the North Shaw suite and are inferred to have been derived from this suite by tectonic processes. Felsic volcanics within the greenstones together with a major portion of the granitic batholiths apparently formed in a calc-alkaline volcanic and plutonic province at ～3,500 Ma. This volcanic and plutonic suite is similar to modern calc-alkaline suites on the basis of major element, rare earh element and most other trace element contents. The Archaean suite contrasts with modern equivalents only in having lower concentrations of HREE and higher concentrations of Ni and Cr. The average composition of the North Shaw suite is similar to that of Archaean gneiss belts for most elements and is consistent with the previously formulated hypothesis that the Shaw Batholith is transitional to the upper crustal level of a high-grade gneiss belt. Enrichment of the gneissic crust in the Shaw Batholith in alkali and heat-producing elements is inferred to have taken place by both igneous and hydrothermal processes over a protracted time interval. Late- and post-tectonic adamellite and granite melts intrude the gneissic rocks and there is isotopic evidence consistent with the gneisses being substantially enriched in Rb by pegmatite injection at ～3,000 Ma.  相似文献