Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-25T23:58:34.016Z Has data issue: false hasContentIssue false
  • English
  • Français

Exsolved magmatic fluid and its role in the formation of comb-layered quartz at the Cretaceous Logtung W-Mo deposit, Yukon Territory, Canada

Published online by Cambridge University Press:  03 November 2011

Jacob B. Lowenstern  and
W. David Sinclair
Jacob B. Lowenstern
Affiliation:
Jacob B. Lowenstern, U.S. Geological Survey, Mail Stop 910, 345 Middlefield Road, Menlo Park, CA 94025, U.S.A.
W. David Sinclair
Affiliation:
W. David Sinclair, Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario, K1A 0E8, Canada
Get access Rights & Permissions [Opens in a new window]

Abstract:

Comb-layered quartz is a type of unidirectional solidification texture found at the roofs of shallow silicic intrusions that are often associated spatially with Mo and W mineralisation. The texture consists of multiple layers of euhedral, prismatic quartz crystals (Type I) that have grown on subplanar aplite substrates. The layers are separated by porphyritic aplite containing equant phenocrysts of quartz (Type II), which resemble quartz typical of volcanic rocks and porphyry intrusions. At Logtung, Type I quartz within comb layers is zoned with respect to a number of trace elements, including Al and K. Concentrations of these elements as well as Mn, Ti, Ge, Rb and H are anomalous and much higher than found in Type II quartz from Logtung or in igneous quartz reported elsewhere. The two populations appear to have formed under different conditions. The Type II quartz phenocrysts almost certainly grew from a high-silica melt between 600 and 800°C (as β-quartz); in contrast, the morphology of Type I quartz is consistent with precipitation from a hydrothermal solution, possibly as α-quartz grown below 600°C. The bulk compositions of comb-layered rocks, as well as the aplite interlayers, are consistent with the hypothesis that these textures did not precipitate solely from a crystallising silicate melt. Instead, Type I quartz may have grown from pockets of exsolved magmatic fluid located between the magma and its crystallised border. The Type II quartz represents pre-existing phenocrysts in the underlying magma; this magma was quenched to aplite during fracturing/degassing events. Renewed and repeated formation and disruption of the pockets of exsolved aqueous fluid accounts for the rhythmic banding of the rocks.

Keywords

volatilesmagmadegassingcomb quartzcomb layeringunidirectional solidification texturesMoWporphyryinfra-redFTIRtrace elements
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 87 , Issue 1-2: Third Hutton Symposium. The Origin of Ganites and Related Rocks , 1996 , pp. 291 - 303
Copyright
Copyright © Royal Society of Edinburgh 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aines, R. D.&Rossman, G. R. 1984. Water in minerals? A peak in the infrared. J GEOPHYS RES 89, 4059–71.CrossRefGoogle Scholar
Aines, R. D., Kirby, S. H.&Rossman, G. R. 1984. Hydrogen speciation in synthetic quartz. PHYS CHEM MINERALS 11, 204–12.CrossRefGoogle Scholar
Barker, D. S. 1970. Compositions of granophyre, myrmekite and graphic granite. GEOL SOC AM BULL 81, 3339–50.CrossRefGoogle Scholar
Brice, J. C. 1985. Crystals for quartz resonators. REV MOD PHYS 57, 105–46.CrossRefGoogle Scholar
Brown, L.&Parsons, I. 1981. Toward a more practical two feldspar geothermometer. CONTRIB MINERAL PETROL 76, 369–77.CrossRefGoogle Scholar
Burnham, C. W. 1967. Hydrothermal fluids at the magmatic stage. In Barnes, H. L. (ed.) Geochemistry of hydrothermal ore deposits, 37–76. New York: Holt, Rinehart & Winston.Google Scholar
Burnham, C. W. 1979. Magmas and hydrothermal fluids. In Barnes, H. L. (ed.) Geochemistry of hydrothermal ore deposits, 71–136. New York: Wiley.Google Scholar
Candela, P. A. 1994. Combined chemical and physical model for pluton devolatilization: a non-Rayleigh fractionalion algorithm. GEOCHIM COSMOCHIM ACTA 58, 2157–67.CrossRefGoogle Scholar
Carten, R. B., Geraghty, E. P., Walker, B. M.&Shannon, J. R. 1988a. Cyclic development of igneous features and their relationship to high-temperature hydrothermal features in the Henderson porphyry molybdenum deposit, Colorado. ECON GEOL 83, 266–96.CrossRefGoogle Scholar
Carten, R. B., Walker, B. M., Geraghty, E. P.&Gunow, A. J. 1988b. Comparison of field-based studies of the Henderson porphyry molybdenum deposit, Colorado, with experimental and theoretical models of porphyry systems. In Taylor, R. P.&Strong, D. F. (eds) Recent advances in the geology of granite-related mineral deposits. CIM SPEC VOL 31, 351–65.Google Scholar
Dennen, W. H. 1966. Stoichiometric substitution in natural quartz. GEOCHIM COSMOCHIM ACTA 30, 1235–41.CrossRefGoogle Scholar
Dennen, W. H. 1967. Trace elements in quartz as indicators of provenance. GEOL SOC AM BULL 78, 125–30.CrossRefGoogle Scholar
Dingwell, D. B. 1988. The structures and properties of fluorine-rich magmas: a review of experimental studies. In Taylor, R. P.&Strong, D. F. (eds) Recent advances in the geology of granite-related mineral deposits. CIM SPEC VOL 31, 1–12.Google Scholar
Gerlach, T., Westrich, H. R.&Symonds, R. B. Pre-eruption vapor saturation in magma of the climactic Mount Pinatubo eruption: source of the giant stratospheric sulfur dioxide cloud. In Newhall, C. (ed.). U.S. GEOL. SURV. PROF. PAP., in press.Google Scholar
Ghiorso, M. S., Carmichael, I. S. E.&Moret, L. K. 1979. Inverted high-temperature quartz: unit cell parameters and properties of the α-β inversion. CONTRIB MINERAL PETROL 68, 307–23.Google Scholar
Haselton, H. T. Jr 1984. The solubility of quartz in dilute HF solutions at 600°C and 1 kbar. EOS, TRANS AM GEOPHYS UNION 65, 308.Google Scholar
Heaney, P. J. 1994. Structure and chemistry of the low-pressure silica polymorphs. In Heaney, P. J., Prewitt, C. T.&Gibbs, G. V. (eds) Silica. MINERAL SOC AM REV MINERAL 29, 1–40.Google Scholar
Hedenquist, J. W.&Lowenstern, J. B. 1994. The role of magmas in the formation of hydrothermal ore deposits. NATURE 370, 519–27.CrossRefGoogle Scholar
Jahns, R. H. 1982. Internal evolution of pegmatite bodies. In Cerny, P. (ed.) Granitic pegmatites in science and industry. MIN SOC CAN SHORT COURSE VOL 8, 293–327.Google Scholar
Johnson, M. C., Anderson, A. T. Jr&Rutherford, M. J. 1994. Preeruptive volatile contents of magmas. In Carrol, M. R.&Holloway, J. R. (eds) Volatiles in magmas. MINERAL SOC AM REV MINERAL 30, 281–330.Google Scholar
Keith, J. D.&Shanks, W. C. III 1988. Chemical evolution and volatile fugacities of the Pine Grove porphyry molybdenum and ash-flow tuff system, southwestern Utah. In Taylor, R. P.&Strong, D. F. (eds) Recent advances in the geology of granite-related mineral deposits. CIM SPEC VOL 31, 402–22.Google Scholar
Keith, J. D., Christiansen, E. H.&Carten, R. B. 1993. The genesis of porphyry molybdenum deposits. In Whiting, B. H., Mason, R.&Hodgson, C. J. (eds) Giant ore deposits. SOC ECON GEOL SPEC PUBL 2, 285–317.Google Scholar
Kirkham, R. V.&Sinclair, W. D. 1988. Comb quartz layers in felsic intrusions and their relationship to porphyry deposits. In Taylor, R. P.&Strong, D. F. (eds) Recent advances in the geology of granite-related mineral deposits. CIM SPEC VOL 31, 50–71.Google Scholar
Kronenberg, A. K. 1994. Hydrogen speciation and chemical weakening of quartz. In Heaney, P. J., Prewitt, C. T.&Gibbs, G. V. (eds) Silica. MIN SOC AM REV MINERAL 29, 123–76.Google Scholar
Lentz, D. R.&Fowler, A. D. 1992. A dynamic model for graphic quartz-feldspar intergrowths in granitic pegmatites in the southwestern Grenville Province. CAN MINERAL 30, 571–85.Google Scholar
Lofgren, G. E.&Donaldson, C. H. 1975. Curved branching crystals and differentiation in comb-layered rocks. CONTRIB MINERAL PETROL 49, 309–19.Google Scholar
London, D. 1992. The application of experimental petrology to the genesis and crystallization of granitic pegmatites. CAN MINERAL 30, 499–540.Google Scholar
Lowenstern, J. B. 1994. Dissolved volatile concentrations in an oreforming magma. GEOLOGY 22, 893–6.Google Scholar
Lowenstern, J. B. 1995. Applications of silicate melt inclusions to the study of magmatic volatiles. In Thompson, J. F. H. (ed.) Magmas fluids and ore deposits. MIN SOC CAN SHORT COURSE VOL 23, 71–100.Google Scholar
Lowenstern, J. B., Mahood, G. A., Hervig, R. L.&Sparks, J. 1993. The occurrence and distribution of Mo and molybdenite in unaltered peralkaline rhyolites from Pantelleria, Italy. CONTRIB MINERAL PETROL 114, 119–29.CrossRefGoogle Scholar
Lu, F. Q., Smith, J. V., Sutton, S. R., Rivers, M. L.&Davis, A. M. 1989. Synchrotron X-ray fluorescence analysis of rock-forming minerals: (1) comparison with other techniques (2) White-beam energy-dispersive procedure for feldspars. CHEM GEOL 75, 123–43.CrossRefGoogle Scholar
Macdonald, R., Smith, R. L.&Thomas, J. E. 1992. Chemistry of the subalkalic silicic obsidians. U.S. GEOL SURV PROF PAP 1523, 214pp.Google Scholar
MacLellan, H. E.&Trembath, L. T. 1991. The role of quartz crystallization in the development and preservation of igneous texture in granitic rocks: experimental evidence at 1 kbar. AM MINERAL 76, 1291–305.Google Scholar
Mainprice, D. H.&Patterson, M. S. 1984. Experimental studies of the role of water in the plasticity of quartzites. J GEOPHYS RES 89, 4257–69.CrossRefGoogle Scholar
Manning, D. A. C.&Pichavant, M. 1988. Volatiles and their bearing on the behaviour of metals in granitic systems. In Taylor, R. P.&Strong, D. F. (eds) Recent advances in the geology of granite-related mineral deposits. CIM SPEC VOL 31, 13–24.Google Scholar
Martin, R. F. 1982. Quartz and the feldspars. In Cerny, P. (ed.) Granitic pegmatites in science and industry. MIN SOC CAN SHORT COURSE VOL 8, 41–62.Google Scholar
Moore, J. G.&Lockwood, J. P. 1973. Origin of comb layering and orbicular structure, Sierra Nevada Batholith, California. GEOL SOC AM BULL 84, 1–20.2.0.CO;2>CrossRefGoogle Scholar
Noble, S. R., Spooner, E. T. C.&Harris, F. R. 1984. The Logtung large tonnage, low-grade W (scheelite)-Mo porphyry deposit, south-central Yukon Territory. ECON GEOL 79, 848–68.CrossRefGoogle Scholar
Pavlishin, V. I., Mazykin, V. V., Matyash, I. V.&Voznyak, D. K. 1978. Variations in the proportion of substitutional aluminum during growth of a quartz crystal. GEOCHEM INT 15, 158–65.Google Scholar
Perny, B., Eberhardt, P., Ramseyer, K., Mullis, J.&Pankrath, R. 1992. Microdistribution of Al, Li and Na in α quartz: possible causes and correlation with short-lived cathodoluminescence. AM MINERAL 77, 534–44.Google Scholar
Scotford, D. M. 1975. A test of aluminum in quartz as a geothermometer. AM MINERAL 60, 139–42.Google Scholar
Shannon, J. R., Walker, B. M., Carten, R. B.&Geraghty, E. P. 1982. Unidirectional solidification textures and their significance in determining relative ages of intrusions at the Henderson Mine, Colorado. GEOLOGY 10, 293–7.2.0.CO;2>CrossRefGoogle Scholar
Shaver, S. A. 1988. Petrology, petrography, and crystallization history of intrusive phases related to the Hall (Nevada Moly) molybdenum deposit, Nye County, Nevada. CAN J EARTH SCI 7, 1000–19.CrossRefGoogle Scholar
Shinohara, H.&Kazahaya, K. 1995. Degassing processes related to magma chamber crystallization. In Thompson, J. F. H. (ed.) Magmas fluids and ore deposits. MIN SOC CAN SHORT COURSE VOL 23, 47–70.Google Scholar
Shinohara, H., Kazahaya, K.&Lowenstern, J. B. 1995. Volatile transport in a convecting magma column: implications for porphyry Mo mineralization. GEOLOGY 23, 1091–4.2.3.CO;2>CrossRefGoogle Scholar
Smith, J. V.&Steele, I. M. 1984. Chemical substitution in silica polymorphs. N JAHRB MINERAL MON 3, 137–44.Google Scholar
Stavrov, O. D., Moiseyev, B. M.&Rakov, L. T. 1979. Relation between content of alkali metals and concentration of aluminum centers in quartz. GEOCHEM INT 15, 5–10.Google Scholar
Stewart, J. P. 1983. Petrology and geochemistry of the intrusives spatially associated with the Logtung W–Mo prospect, southcentral Yukon Territory. M.Sc. Dissertation. University of Toronto.Google Scholar
Swanson, S. E.&Fenn, P. M. 1986. Quartz crystallization in igneous rocks. AM MINERAL 71, 331–42.Google Scholar
Tuttle, O. F.&Bowen, N. L. 1958. Origin of granite in the light of experimental studies in the system NaAlSi3O8 KAlSi3O8-SiO2-H2O. GEOL SOC AM MEM 74.Google Scholar
White, W. H., Bookstrom, A. A., Kamilli, R. J, Gansta, M. W., Smith, R. P., Ranta, D. E.&Steininger, R. C. 1981. Character and origin of Climax-type molybdenum deposits. In Skinner, B. J. (ed.) ECON GEOL 75TH ANNIV VOL 270–316.Google Scholar