Garry Davidson | University of Tasmania (original) (raw)
Papers by Garry Davidson
Vibrational Spectroscopy, 2016
Geology, Aug 1, 2001
Comprehensive studies of the well-preserved, paleo-Archean (3.6 3.2 Ga) Panorama volcanic-hosted ... more Comprehensive studies of the well-preserved, paleo-Archean (3.6 3.2 Ga) Panorama volcanic-hosted massive sulfide district of Western Australia provide compelling evidence that metals were leached from the base of the volcanic pile and redeposited at its top in volcanic-hosted massive sulfide deposits. This leaching provided more than enough metal to form known deposits, implying that direct magmatic input of metal is not required. Sulfur depletion from the base of the volcanic pile was associated with an increase in Fe2O3/FeO and hematitic alteration. These data, combined with sulfur isotope data, indicate that seawater sulfate reduction was facilitated by the oxidation of rock FeO to hematite at high temperature in the H2S stability field. This is the first time that seawater sulfate reduction has been demonstrated regionally in an ancient volcanic-hosted massive sulfide mineral system. The data presented here require paleo-Archean seawater to be sulfate bearing.
Australian Journal of Earth Sciences, May 9, 2007
... In the north, the generally conformable stratigraphic suc-cession is carbonate-poor, younging... more ... In the north, the generally conformable stratigraphic suc-cession is carbonate-poor, younging from the Llewellyn Creek Formation (pelite, arenite), through the Mt Norna Quartzite (quartzo-feldspathic arenite, carbonaceous pelite, metagreywacke, metabasalt, iron-formation) ...
Precambrian Research, 2015
Precambrian Research, 2001
Precambrian Research, 2014
Mineralium Deposita, 2005
Mineralium Deposita, 2006
Mineralium Deposita, 1994
This paper documents the timing, geochemistry and possible origin of sodium enrichment associated... more This paper documents the timing, geochemistry and possible origin of sodium enrichment associated with Proterozoic iron formation-hosted copper-gold ore lenses at the Starra deposit, Australia. The ore lenses are immediately underlain by variably sheared albitemagnetite-hematite-pyrite-bearing rocks, and overlain by mainly unaltered, less-sheared, meta-sediments. Evidence indicating that albite was abundant prior to deformation, and also prior to the main hydrothermal addition of Fe, S, Cu and Au, includes (1) regional albite development at this stratigraphic level; (2) alteration of albite by ore-related sericite; and (3) inclusion of unfoliated inclusions of albite and hematite in ore-related pyrite. Nevertheless, albite also developed around dolerites and within hangingwall shears during metamorphism and deformation. “Least altered” albite footwall rocks have SiO2 (67.31–73.13 wt.%), Al2O3(9.89–12.51 wt.%), total alkali elements (6.40–9.43 wt.%) and HFS elements (e.g., Zr = 179–275 ppm; Ti/Zr = 7.6–14.1) comparable with felsic volcanics, but have high relative Na2O contents (5.08–5.81 wt. %), and variable to high Na2O/K2O ratios (0.05–68.37). An episode of alkali alteration by high-Na fluids prior to the ore-related alteration is postulated to account for sodic compositions, after chemical consideration of the alternatives (1) arkosic sediments; (2) trondhjemitic volcaniclastics; and (3) Na-metasomatism of Staveley Formation sediments. During the most intense ore-alteration, isocon analysis indicates a density increase of ~ 23% compared to the “least altered” albitised hostrocks. Cu, Fe, Au, Sn, W, Zn, K, Ba and Rb were enriched during the mineralising process, whereas Mn, Ca, Si, Nb and Zr were lost, and Al, Ti and Y were not changed (and were used to define the isocon). The loss of some high field strength elements during this alteration indicates that igneous rock classification diagrams based on immobile element ratios should be used with caution for albitemuscovite magnetite-pyrite assemblages associated with iron formation-hosted copper-gold deposits. Zircon was partially soluble, whereas titanium oxides were probably stable in the saline, high temperature (260°–380 °C), acid (pH = 3.9–6.0) fluids envisaged for ore-related alteration.
International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1995
ABSTRACT
Hydrogeology Journal, 2011
Geology, 2003
... Jeffrey C. Alt * ,1 , Garry J. Davidson * ,2 , Damon AH Teagle * ,3 and Jeffrey A. Karson * ,... more ... Jeffrey C. Alt * ,1 , Garry J. Davidson * ,2 , Damon AH Teagle * ,3 and Jeffrey A. Karson * ,4 ... In typical Kuroko volcanogenic sulfide deposits there is no consistent difference in 34 S or 18 O between anhydrite and its massive gypsum replacement (Sakai et al., 1970), indicating ...
Geology, 2001
... Abstract/FREE Full Text. ↵ Canfield, DE, Raiswell, R., Westrich, JT, Reaves, CM, and Berner, ... more ... Abstract/FREE Full Text. ↵ Canfield, DE, Raiswell, R., Westrich, JT, Reaves, CM, and Berner, RA, 1986, The use of chrome reduction in the ... CrossRef. ↵ Stanton, RL, 1990, Magmatic evolution and the ore type–lava type affiliations of volcanic exhalative ores, in Hughes, FE, ed ...
Geology, 1992
... Pb-Zn-Cu volcanogenic massive sulfide deposit (7.4 Mt of 15.5% combined Pb-Zn-Cu, 83 g/t Ag, ... more ... Pb-Zn-Cu volcanogenic massive sulfide deposit (7.4 Mt of 15.5% combined Pb-Zn-Cu, 83 g/t Ag, and 0.52 g/t Au ... Lower Ordovician andesitic, dacitic, and rhyolitic vitric tuffs, siltstone, and mudstone con-formably overlie the volcanic rocks (Trooper Creek Formation, up to 3.4 km ...
Vibrational Spectroscopy, 2016
Geology, Aug 1, 2001
Comprehensive studies of the well-preserved, paleo-Archean (3.6 3.2 Ga) Panorama volcanic-hosted ... more Comprehensive studies of the well-preserved, paleo-Archean (3.6 3.2 Ga) Panorama volcanic-hosted massive sulfide district of Western Australia provide compelling evidence that metals were leached from the base of the volcanic pile and redeposited at its top in volcanic-hosted massive sulfide deposits. This leaching provided more than enough metal to form known deposits, implying that direct magmatic input of metal is not required. Sulfur depletion from the base of the volcanic pile was associated with an increase in Fe2O3/FeO and hematitic alteration. These data, combined with sulfur isotope data, indicate that seawater sulfate reduction was facilitated by the oxidation of rock FeO to hematite at high temperature in the H2S stability field. This is the first time that seawater sulfate reduction has been demonstrated regionally in an ancient volcanic-hosted massive sulfide mineral system. The data presented here require paleo-Archean seawater to be sulfate bearing.
Australian Journal of Earth Sciences, May 9, 2007
... In the north, the generally conformable stratigraphic suc-cession is carbonate-poor, younging... more ... In the north, the generally conformable stratigraphic suc-cession is carbonate-poor, younging from the Llewellyn Creek Formation (pelite, arenite), through the Mt Norna Quartzite (quartzo-feldspathic arenite, carbonaceous pelite, metagreywacke, metabasalt, iron-formation) ...
Precambrian Research, 2015
Precambrian Research, 2001
Precambrian Research, 2014
Mineralium Deposita, 2005
Mineralium Deposita, 2006
Mineralium Deposita, 1994
This paper documents the timing, geochemistry and possible origin of sodium enrichment associated... more This paper documents the timing, geochemistry and possible origin of sodium enrichment associated with Proterozoic iron formation-hosted copper-gold ore lenses at the Starra deposit, Australia. The ore lenses are immediately underlain by variably sheared albitemagnetite-hematite-pyrite-bearing rocks, and overlain by mainly unaltered, less-sheared, meta-sediments. Evidence indicating that albite was abundant prior to deformation, and also prior to the main hydrothermal addition of Fe, S, Cu and Au, includes (1) regional albite development at this stratigraphic level; (2) alteration of albite by ore-related sericite; and (3) inclusion of unfoliated inclusions of albite and hematite in ore-related pyrite. Nevertheless, albite also developed around dolerites and within hangingwall shears during metamorphism and deformation. “Least altered” albite footwall rocks have SiO2 (67.31–73.13 wt.%), Al2O3(9.89–12.51 wt.%), total alkali elements (6.40–9.43 wt.%) and HFS elements (e.g., Zr = 179–275 ppm; Ti/Zr = 7.6–14.1) comparable with felsic volcanics, but have high relative Na2O contents (5.08–5.81 wt. %), and variable to high Na2O/K2O ratios (0.05–68.37). An episode of alkali alteration by high-Na fluids prior to the ore-related alteration is postulated to account for sodic compositions, after chemical consideration of the alternatives (1) arkosic sediments; (2) trondhjemitic volcaniclastics; and (3) Na-metasomatism of Staveley Formation sediments. During the most intense ore-alteration, isocon analysis indicates a density increase of ~ 23% compared to the “least altered” albitised hostrocks. Cu, Fe, Au, Sn, W, Zn, K, Ba and Rb were enriched during the mineralising process, whereas Mn, Ca, Si, Nb and Zr were lost, and Al, Ti and Y were not changed (and were used to define the isocon). The loss of some high field strength elements during this alteration indicates that igneous rock classification diagrams based on immobile element ratios should be used with caution for albitemuscovite magnetite-pyrite assemblages associated with iron formation-hosted copper-gold deposits. Zircon was partially soluble, whereas titanium oxides were probably stable in the saline, high temperature (260°–380 °C), acid (pH = 3.9–6.0) fluids envisaged for ore-related alteration.
International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1995
ABSTRACT
Hydrogeology Journal, 2011
Geology, 2003
... Jeffrey C. Alt * ,1 , Garry J. Davidson * ,2 , Damon AH Teagle * ,3 and Jeffrey A. Karson * ,... more ... Jeffrey C. Alt * ,1 , Garry J. Davidson * ,2 , Damon AH Teagle * ,3 and Jeffrey A. Karson * ,4 ... In typical Kuroko volcanogenic sulfide deposits there is no consistent difference in 34 S or 18 O between anhydrite and its massive gypsum replacement (Sakai et al., 1970), indicating ...
Geology, 2001
... Abstract/FREE Full Text. ↵ Canfield, DE, Raiswell, R., Westrich, JT, Reaves, CM, and Berner, ... more ... Abstract/FREE Full Text. ↵ Canfield, DE, Raiswell, R., Westrich, JT, Reaves, CM, and Berner, RA, 1986, The use of chrome reduction in the ... CrossRef. ↵ Stanton, RL, 1990, Magmatic evolution and the ore type–lava type affiliations of volcanic exhalative ores, in Hughes, FE, ed ...
Geology, 1992
... Pb-Zn-Cu volcanogenic massive sulfide deposit (7.4 Mt of 15.5% combined Pb-Zn-Cu, 83 g/t Ag, ... more ... Pb-Zn-Cu volcanogenic massive sulfide deposit (7.4 Mt of 15.5% combined Pb-Zn-Cu, 83 g/t Ag, and 0.52 g/t Au ... Lower Ordovician andesitic, dacitic, and rhyolitic vitric tuffs, siltstone, and mudstone con-formably overlie the volcanic rocks (Trooper Creek Formation, up to 3.4 km ...