Government of Western Australia Department of Mines and Petroleum RECORD 2014/10 GEOLOGICAL SETTING OF MINERAL DEPOSITS IN THE EASTERN YILGARN CRATON — A FIELD GUIDE compiled by S Wyche Geological Survey of Western Australia Record 2014/10 GEOLOGICAL SETTING OF MINERAL DEPOSITS IN THE EASTERN YILGARN CRATON — A FIELD GUIDE compiled by S Wyche Perth 2014 MINISTER FOR MINES AND PETROLEUM Hon. Bill Marmion MLA DIRECTOR GENERAL, DEPARTMENT OF MINES AND PETROLEUM Richard Sellers EXECUTIVE DIRECTOR, GEOLOGICAL SURVEY OF WESTERN AUSTRALIA Rick Rogerson REFERENCE The recommended reference for this publication is: Wyche, S (compiler) 2014, Geological setting of mineral deposits in the eastern Yilgarn Craton — a field guide: Geological Survey of Western Australia, Record 2014/10, 56p. National Library of Australia Card Number and ISBN 978-1-74168-577-0 Grid references in this publication refer to the Geocentric Datum of Australia 1994 (GDA94). Locations mentioned in the text are referenced using Map Grid Australia (MGA) coordinates, Zone 51. All locations are quoted to at least the nearest 100 m. Disclaimer This product was produced using information from various sources. The Department of Mines and Petroleum (DMP) and the State cannot guarantee the accuracy, currency or completeness of the information. DMP and the State accept no responsibility and disclaim all liability for any loss, damage or costs incurred as a result of any use of or reliance whether wholly or in part upon the information provided in this publication or incorporated into it by reference. Published 2014 by Geological Survey of Western Australia This Record is published in digital format (PDF) and is available online at <www.dmp.wa.gov.au/GSWApublications>. Further details of geological products and maps produced by the Geological Survey of Western Australia are available from: Information Centre Department of Mines and Petroleum 100 Plain Street EAST PERTH WESTERN AUSTRALIA 6004 Telephone: +61 8 9222 3459 Facsimile: +61 8 9222 3444 www.dmp.wa.gov.au/GSWApublications Contents Preface ....................................................................................................................................................................1 Introduction ............................................................................................................................................................1 Yilgarn Craton ........................................................................................................................................................4 Yilgarn granite–greenstones ............................................................................................................................5 Eastern Goldfields — stratigraphy and structure ...................................................................................................7 Stratigraphy .....................................................................................................................................................7 Structure and metamorphism ..........................................................................................................................7 Eastern Goldfields — nickel and gold ...................................................................................................................9 Nickel ..............................................................................................................................................................9 Geodynamic setting of the Kambalda nickel deposits .............................................................................9 Nickel-sulfide mineralization at Kambalda ..............................................................................................9 Gold ..............................................................................................................................................................10 Large-scale lithospheric architecture .....................................................................................................10 Metal sources .........................................................................................................................................10 Timing and structural controls on gold mineralization ..........................................................................10 Summary .......................................................................................................................................................10 Pre-conference excursion — structural and stratigraphic setting of mineral deposits in the Kalgoorlie district .................................................................................................................................................11 Locality 1: Mount Hunt .................................................................................................................................11 Hannan Lake and Mount Hunt ...............................................................................................................11 The Hannan Lake – Mount Hunt traverse .............................................................................................11 Locality 2: Gibson Honman Rock ................................................................................................................15 Locality 3: Navajo Sandstone .......................................................................................................................18 Locality 4: Kurrawang Formation .................................................................................................................18 Locality 5: Mungari Monzogranite ...............................................................................................................18 Locality 6: Spargoville volcanic rocks ..........................................................................................................20 Locality 7: Merougil Formation ....................................................................................................................20 Locality 8: Merougil Formation base ............................................................................................................20 Locality 9: Top of Black Flag Group ............................................................................................................20 Morgans Island .......................................................................................................................................20 Locality 10: Red Hill .....................................................................................................................................21 Locality 11: Kanowna Town Dam ................................................................................................................22 Locality 12: Perkolilli volcanic breccia ........................................................................................................22 Locality 13: Breakaway locality, Kanowna ..................................................................................................22 Locality 14: Harper Lagoon ..........................................................................................................................23 Locality 15: St Ives goldfield ........................................................................................................................25 The Leviathan (Victory–Defiance) gold deposit ....................................................................................25 Locality 16: The Nimbus Ag–Zn–Au deposit ...............................................................................................29 Post-conference excursion — granite–greenstone geology between Kalgoorlie and Leonora ............................30 Locality 1: Western Mining Corporation SM7 nickel laterite pit .................................................................30 Locality 2: Ularring Monzogranite ...............................................................................................................30 Locality 3: Gneiss and granite at 18 Mile Well .............................................................................................34 Locality 4: The Mount Ida greenstone belt near Henderson Well ................................................................35 Locality 4a: Metasedimentary rocks ......................................................................................................35 Locality 4b: Mafic schist ........................................................................................................................35 Locality 5: Pillow basalts at Snake Hill ........................................................................................................35 Locality 6: Copperfield Monzogranite ..........................................................................................................35 Locality 7: Copperfield .................................................................................................................................36 Locality 8: Forest Belle Gabbro ....................................................................................................................36 Locality 9: Raeside paleodrainage ................................................................................................................36 Locality 10: Mount Leonora ........................................................................................................................36