Ian R. Fletcher

Curtin University

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Birger Rasmussen

University of Western Australia

Neal J. McNaughton

Curtin University

Janet R. Muhling

University of Western Australia

David I. Groves

University of Western Australia

Léo Afrâneo Hartmann

Universidade Federal do Rio Grande do Sul

Jian‐Wei Zi

Curtin University

K.J.R. Rosman

Curtin University

Bryan Krapež

Guilin University of Technology

Stephen Sheppard

Geological Survey of Western Australia

Friedhelm Henjes‐Kunst

Federal Institute for Geosciences and Natural Resources

Cooperative Institutions

University of Western Australia

Curtin University

Geological Survey of Western Australia

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Instituto de Geociencias

ARC Centre of Excellence for Core to Crust Fluid Systems

Australian National University

United States Geological Survey

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Australian Research Council

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Major orogenic gold episode associated with Cordilleran-style tectonics related to the assembly of Paleoproterozoic Australia?

Geology (2005)

A.K. Sener Carl S. Young David I. Groves Bryan KrapeIan R. Fletcher

Research Article| March 01, 2005 Major orogenic gold episode associated with Cordilleran-style tectonics related to the assembly of Paleoproterozoic Australia? A. Kerim Şener; A. Kerim Şener 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Carl Young; Carl Young 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar David I. Groves; David I. Groves 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Bryan Krapež; Bryan Krapež 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Ian R. Fletcher Ian R. Fletcher 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information A. Kerim Şener 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Carl Young 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia David I. Groves 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Bryan Krapež 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Ian R. Fletcher 1Centre for Global Metallogeny, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Publisher: Geological Society of America Received: 14 Jul 2004 Revision Received: 18 Nov 2004 Accepted: 26 Nov 2004 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2005) 33 (3): 225–228. https://doi.org/10.1130/G21017.1 Article history Received: 14 Jul 2004 Revision Received: 18 Nov 2004 Accepted: 26 Nov 2004 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation A. Kerim Şener, Carl Young, David I. Groves, Bryan Krapež, Ian R. Fletcher; Major orogenic gold episode associated with Cordilleran-style tectonics related to the assembly of Paleoproterozoic Australia?. Geology 2005;; 33 (3): 225–228. doi: https://doi.org/10.1130/G21017.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract New in situ sensitive high-resolution ion-microprobe (SHRIMP) U-Pb analyses of hydrothermal phosphates associated with orogenic gold mineralization in the Paleoproterozoic Ashburton and Pine Creek gold provinces of northern Australia provide ages of ca. 1740 and ca. 1730 Ma, respectively. Argon-argon analyses of gold-related hydrothermal mica from the Tanami gold province of northern Australia provide ages ca. 1730 Ma. It is important to note that late orogenic events across the western half of Australia coincide with gold metallogenesis across this time interval, in several widely separated provinces. Thus, this orogenic gold episode is interpreted to relate to tectonic events during the amalgamation of various continental blocks to form Paleoproterozoic Australia. It is potentially Earth's best-preserved record of orogenic gold formation during a major early Precambrian continental assembly event. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Metallogeny

Forge

10.1130/g21017.1

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Citations (38)

Archaean gold mineralization synchronous with late cratonization of the Western Dharwar Craton, India: 2.52 Ga U–Pb ages of hydrothermal monazite and xenotime in gold deposits

Mineralium Deposita (2011)

D. Srinivasa Sarma Ian R. Fletcher Birger Rasmussen Neal J. McNaughton M. Ram Mohan

Dharwar Craton

Greenstone belt

Metallogeny

Felsic

10.1007/s00126-010-0326-3

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Citations (121)

A new Paleoproterozoic tectonic history of the eastern Capricorn Orogen, Western Australia, revealed by U–Pb zircon dating of micro-tuffs

Precambrian Research (2016)

Stephen Sheppard Ian R. Fletcher Birger Rasmussen Jian‐Wei Zi Janet R. Muhling

Orogeny

Basement

Siliciclastic

Geochronology

Paleocurrent

10.1016/j.precamres.2016.09.026

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Citations (22)

The 1320 Ma intracontinental Wongawobbin Basin, Pilbara, Western Australia: A far-field response to Albany–Fraser–Musgrave tectonics

Precambrian Research (2016)

Stephen Sheppard Bryan Krapež Jian‐Wei Zi Birger Rasmussen Ian R. Fletcher

10.1016/j.precamres.2016.09.019

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Citations (4)

SHRIMP U/Pb Zircon Dating of Neoproterozoic Granitic Magmatism and Collision in the Pelotas Batholith, Southernmost Brazil

International Geology Review (1999)

Luiz Carlos da Silva Léo Afrâneo Hartmann Neal J. McNaughton Ian R. Fletcher

The introduction of robust geochronological methods for age determinations of the southernmost segment of the Neoproterozoic terranes of Brazil, namely the Dom Feliciano Belt, provides important clues for unraveling the complex evolution of the Brasíliano/Pan-African orogeny in this southwestern portion of the Gondwana supercontinent. Except for associated small schist belts and post-orogenic foreland basins, the belt is represented in this region of southeastern South America by the Pelotas Batholith. Precise SHRIMP U/Pb zircon geochronological techniques based on the study of 95 individual spots on 74 zircon crystals (three samples) and on Nd-isotopic determinations (three samples) are used to assess the late Neoproterozoic history of the belt, especially the orthogneisses interleaved with the batholithic plutons. Three petrotectonic associations were selected for detailed isotopic investigations—the Pinheiro Machado syncollisional monzogranites, the widespread Piratini gneiss tonalitic xenoliths, and the Arroio dos Ratos (now Encantadas) gneiss. The results allow the establishment of the timing and ages of the metamorphic peak and early magmatism. We demonstrate that evolution of Neoproterozoic magmatism within the Pelotas Batholith occurred through a long-lived crustal recycling process from the Paleoproterozoic Rio de la Plata craton. Three major events are recognized, two corresponding to crustal granite generation by partial melting of Paleoproterozoic protoliths at ∼780 and ∼610 Ma, and one related to the high-grade syncollisional metamorphic peak at ∼630 Ma. The data also yield precise criteria to distinguish between thrust-related granitoids of the Dom Feliciano belt and older orthogneisses, both previously interpreted as a unique, pre-collisional, Brasíliano Cycle magmatic-arc association.

Batholith

Protolith

Rodinia

10.1080/00206819909465156

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Citations (103)

Application of U-Th-Pb Phosphate Geochronology to Young Orogenic Gold Deposits: New Age Constraints on the Formation of the Grass Valley Gold District, Sierra Nevada Foothills Province, California

Economic Geology (2015)

Ryan D. Taylor Richard J. Goldfarb Thomas Monecke Ian R. Fletcher Michael A. Cosca

Research Article| August 01, 2015 Application of U-Th-Pb Phosphate Geochronology to Young Orogenic Gold Deposits: New Age Constraints on the Formation of the Grass Valley Gold District, Sierra Nevada Foothills Province, California Ryan D. Taylor; Ryan D. Taylor † 1U.S. Geological Survey, Denver Federal Center, Denver, CO 802252Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO 80401 †Corresponding author: e-mail, rtaylor@usgs.gov Search for other works by this author on: GSW Google Scholar Richard J. Goldfarb; Richard J. Goldfarb 1U.S. Geological Survey, Denver Federal Center, Denver, CO 802253State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China4Centre for Exploration Targeting, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Thomas Monecke; Thomas Monecke 2Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO 80401 Search for other works by this author on: GSW Google Scholar Ian R. Fletcher; Ian R. Fletcher 5Department of Applied Geology, Curtin University, Kent Street, Bentley, WA 6102, Australia Search for other works by this author on: GSW Google Scholar Michael A. Cosca; Michael A. Cosca 1U.S. Geological Survey, Denver Federal Center, Denver, CO 80225 Search for other works by this author on: GSW Google Scholar Nigel M. Kelly Nigel M. Kelly 6Department of Geological Sciences, University of Colorado at Boulder, 2200 Colorado Ave UCB 399, Boulder, CO 80309 Search for other works by this author on: GSW Google Scholar Author and Article Information Ryan D. Taylor † 1U.S. Geological Survey, Denver Federal Center, Denver, CO 802252Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO 80401 Richard J. Goldfarb 1U.S. Geological Survey, Denver Federal Center, Denver, CO 802253State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China4Centre for Exploration Targeting, School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Thomas Monecke 2Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO 80401 Ian R. Fletcher 5Department of Applied Geology, Curtin University, Kent Street, Bentley, WA 6102, Australia Michael A. Cosca 1U.S. Geological Survey, Denver Federal Center, Denver, CO 80225 Nigel M. Kelly 6Department of Geological Sciences, University of Colorado at Boulder, 2200 Colorado Ave UCB 399, Boulder, CO 80309 †Corresponding author: e-mail, rtaylor@usgs.gov Publisher: Society of Economic Geologists Received: 21 Jul 2014 Accepted: 14 Jan 2015 First Online: 09 Mar 2017 Online ISSN: 1554-0774 Print ISSN: 0361-0128 © 2015 Society of Economic Geologists. Economic Geology (2015) 110 (5): 1313–1337. https://doi.org/10.2113/econgeo.110.5.1313 Article history Received: 21 Jul 2014 Accepted: 14 Jan 2015 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Ryan D. Taylor, Richard J. Goldfarb, Thomas Monecke, Ian R. Fletcher, Michael A. Cosca, Nigel M. Kelly; Application of U-Th-Pb Phosphate Geochronology to Young Orogenic Gold Deposits: New Age Constraints on the Formation of the Grass Valley Gold District, Sierra Nevada Foothills Province, California. Economic Geology 2015;; 110 (5): 1313–1337. doi: https://doi.org/10.2113/econgeo.110.5.1313 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEconomic Geology Search Advanced Search Abstract The Grass Valley orogenic gold district in the Sierra Nevada foothills province, central California, the largest historic gold producer of the North American Cordillera, comprises both steeply dipping E-W veins located along lithologic contacts in accreted ca. 300 and 200 Ma oceanic rocks and shallowly dipping N-S veins hosted by the Grass Valley granodiorite; the latter have yielded about 70% of the 13 million ounces of historic lode gold production in the district. The oceanic host rocks were accreted to the western margin of North America between 200 and 170 Ma, metamorphosed to greenschist and amphibolite facies, and uplifted between 175 and 160 Ma. Large-scale magmatism in the Sierra Nevada occurred between 170 to 140 Ma and 120 to 80 Ma, with the Grass Valley granodiorite being emplaced during the older episode of magmatism.Uranium-lead isotope dating of hydrothermal xenotime yielded the first absolute age of 162 ± 5 Ma for the economically more significant N-S veins. The vein-hosted xenotime, as well as associated monazite, are unequivocally of hydrothermal origin as indicated by textural and chemical characteristics, including grain shape, lack of truncated growth banding, lack of an Eu anomaly, and low U and Th concentrations. Furthermore, the crack-seal texture of the veins, with abundant wall-rock slivers, suggests their formation as a result of episodic fluid flow possibly related to reoccurring seismic events, rather than a period of fluid exsolution from an evolving magma. The N-S veins are temporally distinct from a younger 153 to 151 Ma gold event that was previously reported for the E-W veins.Overlapping U-Pb zircon (159.9 ± 2.2 Ma) and 40Ar/39Ar biotite and hornblende (159.7 ± 0.6–161.9 ± 1.4 Ma) ages and geothermobarometric calculations indicate that the Grass Valley granodiorite was emplaced at ca. 160 Ma at elevated temperatures (~800°C) within approximately 3 km of the paleosurface and rapidly cooled to the ambient temperature of the surrounding country rocks (<300°C). The age of the granodiorite is indistinguishable from that of the N-S veins, as recorded by the U-Pb age of xenotime in those veins. Consequently, the N-S veins must have formed between 162 and 157 Ma, the maximum permissive age of magma emplacement and the youngest permissive xenotime U-Pb age, respectively, during an E- to ENE-directed compressional regime. The geochemistry of the Grass Valley granodiorite is consistent with it being the product of arc magmatism. It served as a receptive host for mineralization, but it is has no direct genetic relationship to gold mineralization. Initial uplift of the intrusive mass correlates with the initial voluminous fluid flow event and vein formation at depths of no greater than 3 km. The E-W gold-bearing veins hosted within greenschist-facies country rocks adjacent to the intrusion formed during a second hydrothermal event 5 to 10 million years later than the magmatism and were contemporaneous with a shift to transtensional deformation denoted by sinistral strike-slip faulting. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Foothills

Geochronology

10.2113/econgeo.110.5.1313

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Citations (49)

Giant iron-ore deposits of the Hamersley province related to the breakup of Paleoproterozoic Australia: New insights from in situ SHRIMP dating of baddeleyite from mafic intrusions

Geology (2005)

Stefan Müller Bryan KrapeMark Barley Ian R. Fletcher

Research Article| July 01, 2005 Giant iron-ore deposits of the Hamersley province related to the breakup of Paleoproterozoic Australia: New insights from in situ SHRIMP dating of baddeleyite from mafic intrusions Stefan G. Müller; Stefan G. Müller 1School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Bryan Krapež; Bryan Krapež 1School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Mark E. Barley; Mark E. Barley 1School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Ian R. Fletcher Ian R. Fletcher 1School of Earth and Geographical Sciences, University of Western Australia, Crawley, WA 6009, Australia Search for other works by this author on: GSW Google Scholar Geology (2005) 33 (7): 577–580. https://doi.org/10.1130/G21482.1 Article history received: 21 Dec 2004 rev-recd: 16 Mar 2005 accepted: 17 Mar 2005 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Stefan G. Müller, Bryan Krapež, Mark E. Barley, Ian R. Fletcher; Giant iron-ore deposits of the Hamersley province related to the breakup of Paleoproterozoic Australia: New insights from in situ SHRIMP dating of baddeleyite from mafic intrusions. Geology 2005;; 33 (7): 577–580. doi: https://doi.org/10.1130/G21482.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Banded iron formations of the ca. 2770–2405 Ma Hamersley province of Western Australia were locally upgraded to high-grade hematite ores during the Early Paleoproterozoic by a combination of hypogene and supergene processes after the initial rise of atmospheric oxygen. Ore genesis was associated with the stratigraphic break between the Lower and Upper Wyloo Groups of the Ashburton province, and has been variously linked to the Ophthalmian orogeny, late-orogenic extensional collapse, and anorogenic continental extension. Small-spot in situ Pb/Pb dating of baddeleyite by sensitive high-resolution ion microprobe (SHRIMP) has resolved the ages of two key suites of mafic intrusions, constraining for the first time the tectonic evolution of the Ashburton province and the age and setting of iron-ore formation. Mafic sills dated as ca. 2208 Ma were folded during the Ophthalmian orogeny and then cut by the unconformity at the base of the Lower Wyloo Group. A mafic dike swarm that intrudes the Lower Wyloo Group and has a close genetic relationship to iron ore is ca. 2008 Ma, slightly younger than a new syneruptive 2031 ± 6 Ma zircon age for the Lower Wyloo Group. These new ages constrain the Ophthalmian orogeny to the period between ca. 2208 and 2031 Ma, before Lower Wyloo Group extension, sedimentation, and flood-basalt volcanism. The ca. 2008 Ma dikes pre s ent a new maximum age for iron-ore genesis and deposition of the Upper Wyloo Group, thereby linking ore genesis to a ca. 2050–2000 Ma period of continental extension similarly recorded by Paleoproterozoic terrains worldwide well after the initial oxidation of the atmosphere by ca. 2320 Ma. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Baddeleyite

10.1130/g21482.1

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Citations (113)

Ion microprobe (NanoSIMS 50) Pb-isotope geochronology at <5μm scale

International Journal of Mass Spectrometry (2005)

Richard A. Stern Ian R. Fletcher Birger Rasmussen Neal J. McNaughton Brendan Griffin

Microprobe

Geochronology

Uraninite

Zirconolite

10.1016/j.ijms.2005.05.005

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Citations (45)

Archean-Proterozoic Evolution of Indian Charnockites: Isotopic and Geochemical Evidence from Granulites of the Eastern Ghats Belt

The Journal of Geology (1990)

D. K. Paul T. Ray Barman N. J. McNaughton Ian R. Fletcher Philip J. Potts

Pyroxene granulites and charnockites are associated with metasedimentary khondalite (garnet-sillimanite gneiss) and migmatites in the Eastern Ghats mobile belt. Various stages of in situ granulitization similar to those observed in southern India and Sri Lanka are present. Geochemically the granulite suite around Visakhapatnam is bimodal, with acid and mafic variants. There is an increase in the concentration and fractionation of the rare earth elements (REE) from pyroxene granulites to charnockites, and six Sm-Nd models ages () range from 2.86 to 2.35 Ga, with 2.1 Ga for a younger granite. The charnockites, a pyroxene granulite, and granite define a Pb/Pb isochron age of . U-Pb ages of zircons and monazites from a charnockite near Phulbani, Orissa, yield near concordant data with ages of and , respectively. The new isotopic data and the available ages from the northeastern part of the Eastern Ghats in Orissa suggest a major charnockite formation event between ca. 1170 and 950 Ma. This event is contemporaneous with that of Sri Lanka but much younger than the late Archean granulite event in southern India.

Charnockite

Pyroxene

Migmatite

10.1086/629396

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Citations (152)

Evidence from U–Pb zircon and ⁴⁰Ar/³⁹Ar muscovite detrital mineral ages in metasandstones for movement of the Torlesse suspect terrane around the eastern margin of Gondwanaland

Terra Nova (1998)

C.J. Adams M. E. Barley Ian R. Fletcher A.L. Pickard

New U–Pb detrital zircon ages from Triassic metasandstones of the Torlesse Terrane in New Zealand are compared with 40 Ar/ 39 Ar muscovite data and together, reveal four main source components: (i) major, Triassic–Permian (210–270 Myr old) and (ii) minor, Permian–Carboniferous (280–350 Myr old) granitoids (recorded in zircon and muscovite data); (iii) minor, early middle Palaeozoic, metamorphic rocks, recorded mainly by muscovite, 420–460 Myr old, and (iv) minor, Late Precambrian–Cambrian igneous and metamorphic complexes, 480–570 Myr old, recorded by zircon only. There are also Proterozoic zircon ages with no clear grouping (580–1270 Myr). The relative absence of late Palaeozoic (350–420 Myr old) components excludes granitoid terranes in the southern Lachlan Fold Belt (Australia) and its continuation into North Victoria Land (East Antarctica) and Marie Byrd Land (West Antarctica) as a potential source for the Torlesse. The age data are compatible with derivation from granitoid terranes of the northern New England Orogen (and hinterland) in NE Australia. This confirms that the Torlesse Terrane of New Zealand is a suspect terrane, that probably originated at the NE Australian, Permian–Triassic, Gondwanaland margin and then (200–120 Ma) moved 2500 km southwards to its present New Zealand position by the Late Cretaceous (90 Ma). This sense of movement is analogous to that suggested for Palaeozoic Mesozoic terranes at the North American Pacific margin.

10.1046/j.1365-3121.1998.00186.x

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Citations (54)