Eastern Goldfield Province
The Archaean Norseman-Wiluna Greenstone Belt in the Eastern Goldfield Province contains most of Australia's lode gold deposits, including the famous Kalgoorlie Golden Mile containing the Super Pit.
These gold deposits are generally of large tonnage and are confined to the volcanic-intrusive-sedimentary sequences of the greenstone belts and not the granites. There is a pattern of gold distribution along the Archean Boulder-Lefroy shear zone.
Intrusive komatiites (ultramafic volcanic rocks) occur along the Norseman-Wiluna Greenstone Belt. A change from volcanic-dominated to plutonic-dominated magmatism occurred in the Norseman-Wiluna Greenstone Belt approximately 2685–2675 Ma. Voluminous high-Ca granite intrusions occurred 2670–2655 Ma. Much of the gold was deposited between 2650–2630 Ma, with much of this associated with strike-slip reactivation of earlier faults (normal and reverse).
An earlier gold event 2660-2655 Ma was associated with major extension (normal faulting and granite doming) resulting in the formation of late basins and the intrusion of mantle-derived magmas (syenites and Mafic-type granites/porphyries) and tight anticlockwise PTt paths.
Read more about this topic: Yilgarn Craton
Famous quotes containing the words eastern and/or province:
“I need not tell you of the inadequacy of the American shipping marine on the Pacific Coast.... For this reason it seems to me that there is no subject to which Congress can better devote its attention in the coming session than the passage of a bill which shall encourage our merchant marine in such a way as to establish American lines directly between New York and the eastern ports and South American ports, and both our Pacific Coast ports and the Orient and the Philippines.”
—William Howard Taft (18571930)
“Female Virtues are of a Domestick turn. The Family is the proper Province for Private Women to Shine in. If they must be showing their Zeal for the Publick, let it not be against those who are perhaps of the same Family, or at least of the same Religion or Nation, but against those who are the open, professed, undoubted Enemies of their Faith, Liberty, and Country.”
—Joseph Addison (16721719)