Osmium isotope constraints on ore metal recycling in subduction zones

Science

Volumn 286, Issue 5439, 1999, Pages 512-516

  McInnes, Brent I A ^a   McBride, Jannene S ^b   Evans, Noreen J ^a   Lambert, David D ^b   Andrew, Anita S ^a  

^a CSIRO   (Australia)

^b MONASH UNIVERSITY   (Australia)

Author keywords

[No Author keywords available]

Indexed keywords

COPPER; GOLD; OSMIUM;

EPITHERMAL DEPOSIT; ISOTOPIC COMPOSITION; MANTLE SOURCE; METAL; OSMIUM; SUBDUCTION ZONE;

ARTICLE; GEOLOGY; PAPUA NEW GUINEA; PRIORITY JOURNAL; VOLCANO;

EID: 0033569672     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.286.5439.512     Document Type: Article

References (65)

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3. R. H. Sillitoe, Econ. Geol. 67, 184 (1972); A. H. G. Mitchell and M. S. Garson, Inst. Mining Metall. Trans. 81, B10 (1972); F. J. Sawkins, J. Geol. 80, 377 (1972).
4. Pd, Pt, and Ru are commonly enriched in sulfide concentrates from porphyry deposits with the highest contents being recorded from gold-rich deposits, particularly those associated with alkaline porphyries [R. H. Sillitoe, in Unconventional Metal Deposits, W. C. Shanks, Ed. (American Institute of Mining, Metallurgy and Petroleum Engineering, New York, 1983), p. 207; F. E. Mutschler et al., Trans. Geol. Soc. S. Afr. 88, 355 (1985); D. Eliopoulos and M. Economou-Eliopoulos, Econ. Geol. 86, 740 (1991); M. Tarkain and G. Koopman, Mineral. Deposita 30, 39 (1995)]. Re and Os contents of base metal sulfides from the El Teniente porphyry Cu deposit in Chile range from 53 to 180 ppt and from 44 to 874 ppt, respectively [C. Freydier et al., Geology 25, 775 (1997)].
5. Pd, Pt, and Ru are commonly enriched in sulfide concentrates from porphyry deposits with the highest contents being recorded from gold-rich deposits, particularly those associated with alkaline porphyries [R. H. Sillitoe, in Unconventional Metal Deposits, W. C. Shanks, Ed. (American Institute of Mining, Metallurgy and Petroleum Engineering, New York, 1983), p. 207; F. E. Mutschler et al., Trans. Geol. Soc. S. Afr. 88, 355 (1985); D. Eliopoulos and M. Economou-Eliopoulos, Econ. Geol. 86, 740 (1991); M. Tarkain and G. Koopman, Mineral. Deposita 30, 39 (1995)]. Re and Os contents of base metal sulfides from the El Teniente porphyry Cu deposit in Chile range from 53 to 180 ppt and from 44 to 874 ppt, respectively [C. Freydier et al., Geology 25, 775 (1997)].
6. Pd, Pt, and Ru are commonly enriched in sulfide concentrates from porphyry deposits with the highest contents being recorded from gold-rich deposits, particularly those associated with alkaline porphyries [R. H. Sillitoe, in Unconventional Metal Deposits, W. C. Shanks, Ed. (American Institute of Mining, Metallurgy and Petroleum Engineering, New York, 1983), p. 207; F. E. Mutschler et al., Trans. Geol. Soc. S. Afr. 88, 355 (1985); D. Eliopoulos and M. Economou-Eliopoulos, Econ. Geol. 86, 740 (1991); M. Tarkain and G. Koopman, Mineral. Deposita 30, 39 (1995)]. Re and Os contents of base metal sulfides from the El Teniente porphyry Cu deposit in Chile range from 53 to 180 ppt and from 44 to 874 ppt, respectively [C. Freydier et al., Geology 25, 775 (1997)].
7. Pd, Pt, and Ru are commonly enriched in sulfide concentrates from porphyry deposits with the highest contents being recorded from gold-rich deposits, particularly those associated with alkaline porphyries [R. H. Sillitoe, in Unconventional Metal Deposits, W. C. Shanks, Ed. (American Institute of Mining, Metallurgy and Petroleum Engineering, New York, 1983), p. 207; F. E. Mutschler et al., Trans. Geol. Soc. S. Afr. 88, 355 (1985); D. Eliopoulos and M. Economou-Eliopoulos, Econ. Geol. 86, 740 (1991); M. Tarkain and G. Koopman, Mineral. Deposita 30, 39 (1995)]. Re and Os contents of base metal sulfides from the El Teniente porphyry Cu deposit in Chile range from 53 to 180 ppt and from 44 to 874 ppt, respectively [C. Freydier et al., Geology 25, 775 (1997)].
8. Pd, Pt, and Ru are commonly enriched in sulfide concentrates from porphyry deposits with the highest contents being recorded from gold-rich deposits, particularly those associated with alkaline porphyries [R. H. Sillitoe, in Unconventional Metal Deposits, W. C. Shanks, Ed. (American Institute of Mining, Metallurgy and Petroleum Engineering, New York, 1983), p. 207; F. E. Mutschler et al., Trans. Geol. Soc. S. Afr. 88, 355 (1985); D. Eliopoulos and M. Economou-Eliopoulos, Econ. Geol. 86, 740 (1991); M. Tarkain and G. Koopman, Mineral. Deposita 30, 39 (1995)]. Re and Os contents of base metal sulfides from the El Teniente porphyry Cu deposit in Chile range from 53 to 180 ppt and from 44 to 874 ppt, respectively [C. Freydier et al., Geology 25, 775 (1997)].
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18. J. C. Foster et al., Nature 382, 703, (1996); D. D. Lambert et al., Econ. Geol. 93, 121 (1998); D. D. Lambert et al., J. Petrol. 35, 1717, (1994); T. E. McCandless and J. Ruiz, Geology 19, 1225 (1991); R. J. Walker et al., Earth. Planet. Sci. Lett. 105, 416, (1991); R. J. Walker et al., Geochim. Cosmochim. Acta 58, 4179 (1994).
19. D. D. Lambert, J. G. Foster, L. R. Frick, D. M. Hoatson, A. C. Purvis, Austr. J. Earth. Sci. 45, 265 (1998).
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21. E. Widom and P. Kepezhinskas, Eos Trans. 80, 354 (1999).
22. P. Herzig et al., ibid. 75, 513 (1994); P. M. Herzig and M. D. Hannington, in PACRIM Congress 1995, J. L. Mauk and J. D. St. George, Eds. (The Australasian Institute of Mining and Metallurgy, Auckland, New Zealand, 1995), vol. 9, pp. 279-284. Some of the samples used in this study were collected during Cruise SO-94 of RV Sonne (Edison project), which was organized by Freiberg University of Mining and Technology and funded by the German Federal Ministry for Research and Technology (BMFT grant 03G0094A to P. Herzig).
23. P. Herzig et al., ibid. 75, 513 (1994); P. M. Herzig and M. D. Hannington, in PACRIM Congress 1995, J. L. Mauk and J. D. St. George, Eds. (The Australasian Institute of Mining and Metallurgy, Auckland, New Zealand, 1995), vol. 9, pp. 279-284. Some of the samples used in this study were collected during Cruise SO-94 of RV Sonne (Edison project), which was organized by Freiberg University of Mining and Technology and funded by the German Federal Ministry for Research and Technology (BMFT grant 03G0094A to P. Herzig).
24. B. I. A. McInnes, P. M. Herzig, M. D. Hannington, R. A. Binns, Eos 75, 747 (1994); B. I. A. McInnes, in The Composition and Structure of Oceanic Lithosphere at a Convergent Plate Boundary, R. Williams and H. Sloan, Eds. (ODP-InterRidge-IAVCEI, The Oceanic Lithosphere & Scientific Drilling into the 21st Century, Woods Hole, MA, 1996); B. I. A. McInnes, in Research Review (Commonwealth Scientific and Industrial Research Organization Exploration and Mining, North Ryde, New South Wales, Australia, 1999), vol. 1, pp. 11-13.
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27. The sedimentary stratigraphy of the New Ireland Basin has been determined during geological and geophysical surveys [N. F. Exon et al., Bur. Miner. Resour. J. Austr. Geol. Geophys. 10, 39 (1986)]. The minimum depth estimate of 17 km for the ultramafic rocks is based on the depth of the Moho [A. S. Furomoto et al., Tectonophysics 34, 71 (1976)], and the maximum depth of 70 km is based on the absence of garnet-bearing peridotites.
28. The sedimentary stratigraphy of the New Ireland Basin has been determined during geological and geophysical surveys [N. F. Exon et al., Bur. Miner. Resour. J. Austr. Geol. Geophys. 10, 39 (1986)]. The minimum depth estimate of 17 km for the ultramafic rocks is based on the depth of the Moho [A. S. Furomoto et al., Tectonophysics 34, 71 (1976)], and the maximum depth of 70 km is based on the absence of garnet-bearing peridotites.
29. B. I. A. McInnes, M. Gregoire, R. A. Binns, P. M. Herzig, M. D. Hannington, unpublished data; M. Gregoire, B. I. A. McInnes, S. O'Reilly, unpublished data.
30. B. I. A. McInnes, M. Gregoire, R. A. Binns, P. M. Herzig, M. D. Hannington, unpublished data; M. Gregoire, B. I. A. McInnes, S. O'Reilly, unpublished data.
31. 2) units above the fayalite-magnetite-quartz buffer (FMQ)] (9, 11).
32. 2 flux, dissolved in HCl, and combined with the HF-aqua regia supernatant. Tellurium coprecipitation of PGE with stannous chloride (30) was used to separate analyte from matrix components. Filtered precipitate was dissolved in aqua regia and analyzed in 5 ml of 1.5 M nitric acid. Analysis of solutions on a Perkin Elmer Siex Elan model 5000 yielded detection limits of 0.1 part per billion (ppb) for Au and Pt, 0.01 to 0.05 ppb for Rh and Ru, and 0.006 ppb for Ir. These values were calculated as three times the standard deviation for the 10 reagent blanks. Precision for the technique as percent standard deviation for repeated analysis of Canadian Certified Reference Materials Project reference WGB-1 is 6% for Ir and Ru, 8% for Pt, 10% for Pd, 11% for Rh, and 14% for Au.
33. 2 = FMQ ± 1) have been calculated [D. C. Sassani and E. L. Shock, Geology 18, 925 (1990)]. There are petrologic data for PGE enrichment under supercritical conditions in ophiolites [H. M. Prichard and M. Tarkian, Can. Mineral. 26, 979 (1988)] and mafic intrusions [A. E. Boudreau, E. A. Mathez, I. S. McCallum, J. Petrol. 27, 967 (1986)].
34. 2 = FMQ ± 1) have been calculated [D. C. Sassani and E. L. Shock, Geology 18, 925 (1990)]. There are petrologic data for PGE enrichment under supercritical conditions in ophiolites [H. M. Prichard and M. Tarkian, Can. Mineral. 26, 979 (1988)] and mafic intrusions [A. E. Boudreau, E. A. Mathez, I. S. McCallum, J. Petrol. 27, 967 (1986)].
35. 2 = FMQ ± 1) have been calculated [D. C. Sassani and E. L. Shock, Geology 18, 925 (1990)]. There are petrologic data for PGE enrichment under supercritical conditions in ophiolites [H. M. Prichard and M. Tarkian, Can. Mineral. 26, 979 (1988)] and mafic intrusions [A. E. Boudreau, E. A. Mathez, I. S. McCallum, J. Petrol. 27, 967 (1986)].
36. 2 = FMQ ± 1) have been calculated [D. C. Sassani and E. L. Shock, Geology 18, 925 (1990)]. There are petrologic data for PGE enrichment under supercritical conditions in ophiolites [H. M. Prichard and M. Tarkian, Can. Mineral. 26, 979 (1988)] and mafic intrusions [A. E. Boudreau, E. A. Mathez, I. S. McCallum, J. Petrol. 27, 967 (1986)].
37. Isotopic analysis of 5 g of rock powder yielded higher Os and Re abundances (4.5 ppb Os and 0.11 ppb Re) and γOs values (+40) than duplicate 1-g analyses (0.55 ppb Os, 0.05 ppb Re, and γOs = +5 to +7). This suggests that the larger 5-g aliquot has sampled a heterogeneously distributed sulfide phase, which the smaller 1-g aliquots have missed (the nugget effect) (30-32). Mitchell and Keays (31) determined that the bulk (60 to 80%) of the PGEs and Au in the mantle are contained in sulfide-rich intergranular components in spinel lherzolite xenoliths. Hart and Ravizza (32) demonstrated that most Os in spinel lherzolite xenoliths from Kilboume Hole was contained in sulfides (3.55 ppm Os), whereas olivine contained only 36 ppt Os.
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39. P. Schiano, J.-L. Birck, C. J. Allegre, Earth Planet. Sci. Lett. 150, 363 (1997); E. H. Hauri and S. R. Hart, Chem. Geol. 139, 185 (1997).
40. mantle = 0.40076 [R. J. Walker and J. W. Morgan, Science 243, 519 (1989)]. γOs is defined as the percentage difference between the sample and chondritic mantle at present day.
41. mantle = 0.40076 [R. J. Walker and J. W. Morgan, Science 243, 519 (1989)]. γOs is defined as the percentage difference between the sample and chondritic mantle at present day.
42. mantle = 0.40076 [R. J. Walker and J. W. Morgan, Science 243, 519 (1989)]. γOs is defined as the percentage difference between the sample and chondritic mantle at present day.
43. mantle = 0.40076 [R. J. Walker and J. W. Morgan, Science 243, 519 (1989)]. γOs is defined as the percentage difference between the sample and chondritic mantle at present day.
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45. 188Os = 0.17367 ± 0.00058 [external reproducibility at the 2σ level (n = 24) using a peak-jumping routine and a secondary electron multiplier], within error of the DTM value of 0.17429 ± 0.00055 [S. B. Shirey, Can. J. Earth Sci. 34, 489 (1997)] (5). There is no measurable bias introduced into the data from our mass spectrometer (Finnigan MAT 262 N-TIMS) relative to results produced at DTM.
46. 188Os = 0.17367 ± 0.00058 [external reproducibility at the 2σ level (n = 24) using a peak-jumping routine and a secondary electron multiplier], within error of the DTM value of 0.17429 ± 0.00055 [S. B. Shirey, Can. J. Earth Sci. 34, 489 (1997)] (5). There is no measurable bias introduced into the data from our mass spectrometer (Finnigan MAT 262 N-TIMS) relative to results produced at DTM.
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50. The Lihir ore samples are from the Ladolam gold deposit and were selected from G. Carman's (1993) unpublished Ph.D thesis collection, Monash University. Sample 101373 is a biotite-altered basaltic breccia from the Minifie area containing the following alteration assemblage: biotite, potassium-containing feldspar (k-feldspar), anhydrite, calcite, pyrite, albite, quartz, adularia, chalcopyrite, tetrahedrite, electrum, galena, sphalerite, and argentite. Sample 101201 is a heterolithic breccia of mainly mafic lavas from the Lienetz area containing the following alteration assemblage: biotite, tourmaline, k-feldspar, albite, sericite, pyrite, magnetite, anhydrite, calcite, marcasite, and pyrrhotite.
51. K-Ar ages reported for various stages of hydrothermal alteration at the Ladolam gold deposit on Lihir island include the following: biotite separate from potassic altered volcanic rock age of 917 ± 100 Ka, biotite separate from biotite pyroxenite monzonite age of 343 ± 36 Ka, biotite separate from biotite-anhydrite vein age of 336 ± 27 Ka, and alunite-rich whole rock age of 151 ± 15 Ka [R. M. Davies and G. H. Ballantyne, in PACRIM Congress 1987 (Australasian Institute of Mining and Metallargy, Gold Coast, Australia, 1987), vol. 1, pp. 943-994].
52. 2 was analyzed automatically on a Finnigan 252 mass spectrometer against an internal standard. Two quartz standards were run with every 10 samples. Replicate analysis of the standard quartz is generally better than ±0.2. Analyses are reported in per mil relative to the standard mean ocean water (SMOW) standard.
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58. 18O values ranging from 9.0 to 11.3‰ ± 1.1‰; J. M. Eiler, B. I. A. McInnes, J. W. Valley, C. M. Graham, E. M. Stolper, Nature 393, 777 (1998).
59. 18O = 11.3‰ from mantle wedge xenocrysts found elsewhere in the Tabar-Lihir-Tanga-Feni arc (27). The value of 12‰ is consistent with values obtained from seawater-altered basalt (5.7 to 12‰) from the upper 1 to 2 km of oceanic crust from ophiolite sequences (26).
60. 188Os = 0.122 to 0.1271, Os = 3.5 ppb; see Table 1 and (18)].
61. S. B. Shirey and R. W. Walker, Anal. Chem. 67, 2136 (1995)
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63. S. R. Hart and G. Ravizza, Eos 120 (1993).
64. W. F. McDonough and S.-s. Sun, Chem. Geol. 120, 223 (1995).
65. We thank John Byrne and Jim Keegan for assistance in determining PGE contents, Brad McDonald for oxygen isotope analysis, and Eva Mylka for drafting. The comments of the anonymous reviewers helped clarify the presentation.