Abstract
Summary Porphyry copper deposits are large crustal sulphur anomalies containing copper and other metals. Much of the sulphur is oxidized and, along with a major portion of the copper, deposited from fluids evolved from certain calc-alkaline melts of intermediate composition. These melts are emplaced with characteristic textures as dykes and stocks in and above the cupolas of small granitic batholiths. The depth of emplacement is shallow, and the intrusions are comagmatic with overlying andesite—rhyolite volcanics. Intrusion and mineralization are relatively rapid events and occur towards the end of previous episodes of vulcanism and intrusion. Porphyry copper deposits are clustered in both space and time on regional, continental and global scales. More may have formed in the past 65 million years than in earlier geologic periods, especially in certain apparently favourable continental regions. Sources of sulphur, copper and of the associated magmas are unknown. Much additional mapping of continental and oceanic margins is needed to explain the abnormal, or unusual, coincidence of several igneous and tectonic processes probably responsible for the formation of porphyry copper deposits.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
