Bottle Creek |
|
Western Australia, WA, Australia |
Main commodities:
Au Ag
|
|
|
|
|
|
Super Porphyry Cu and Au
|
IOCG Deposits - 70 papers
|
All papers now Open Access.
Available as Full Text for direct download or on request. |
|
|
The Bottle Creek gold deposit is located 210 km north-west of Kalgoorlie and ~100 km NW of Menzies within the Ularring greenstone belt, the western most of the Kalgoorlie Terrane of the Archaean Yilgarn Craton in Western Australia.
The deposit is located along the Mt Ida Shear zone that defines the western margin of the Kalgoorlie Terrane, and was discovered in 1983. It was considered by various companies. Mining was started by Norgold in 1988, but closed only one year later due to a limited gold resource.
In the Bottle Creek area the host greenstone sequence can be divided into i). a lower sequence to the west of east dipping and younging banded iron formation with interbedded mafic volcanics, quartzites and conglomerates, and ii). an upper sequence to the east of mafic and ultramafic rocks with minor interflow sediments, quartz porphyry intrusives and tuffs. These sequences are flanked by granitoids.
The Bottle Creek mineralisation is found close to the contact of the two sequences, near the top of the older suite and coincides with a sheared, 10 m thick black shale unit with an associated felsic porphyry which may be traced for 26 km along strike. The black shale is flanked by quartz-mica schists, banded amphibolite and minor spinifex textured ultramafics to the east and by quartz-biotite schists and mafic volcanics to the west. These schists have been subjected to potash metasomatism, silicification and carbonatisation. At surface the sheared black shale is a gossanous ironstone and has been oxidised and lateritised to a depth of 100 m.
Below the base of weathering and oxidation, a massive pyrite-pyrrhotite zone up to 6 m thick occurs within the sheared black shale in a variable gangue of quartz and white mica, coarse grained quartz, siliceous graphitic schist, grunerite-chlorite schist, garnet pods and ankerite-calcite-biotite-hornblende-quartz schist. Silver occurs within tetrahedrite, arsenical pyrite, pyrrhotite, sphalerite, arsenopyrite, chalcopyrite and electrum within the massive sulphides. Based on limited drilling the gold in the primary sulphides averages around 1 g/t.
Ore grade microfine free gold occurs as free particles and inclusions in quartz, limonite, goethite and in beudanite (an Fe-As-Pb sulphate), upgraded in the oxide zone at depths of between 30 and 60 m below surface, concentrated in zones that are generally 10 to 15 m wide and 500 to 1000 m long, spread intermittently over a strike length of 10 km.
The total resource in 1987 was - 1.9 Mt @ 3.5 g/t Au, 27 g/t Ag.
For detail consult the reference(s) listed below.
The most recent source geological information used to prepare this decription was dated: 1990.
This description is a summary from published sources, the chief of which are listed below. © Copyright Porter GeoConsultancy Pty Ltd. Unauthorised copying, reproduction, storage or dissemination prohibited.
|
|
Legge P J, Mill J H A, Ringrose C R, McDonald I R 1990 - Bottle Creek Gold deposit: in Hughes F E (Ed.), 1990 Geology of the Mineral Deposits of Australia & Papua New Guinea The AusIMM, Melbourne Mono 14, v1 pp 357-361
|
Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge. It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published. While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo, its employees and servants: i). do not warrant, or make any representation regarding the use, or results of the use of the information contained herein as to its correctness, accuracy, currency, or otherwise; and ii). expressly disclaim all liability or responsibility to any person using the information or conclusions contained herein.
|
Top | Search Again | PGC Home | Terms & Conditions
|
|