Abstract
Although prior to 20 years ago, greenstones were thought to represent an Archean phenomenon, it is now clear that greenstones have formed throughout geologic time. It seems to be equally clear that all greenstones do not represent the same tectonic setting, nor do the proportions of preserved greenstones of a given age and tectonic setting necessarily reflect the original proportions of that tectonic setting. To better understand the tectonic settings of greenstones and their role in the history of continents and ocean basins, it is of interest to compare greenstones through time. Some studies have compared the geochemistry of greenstone volcanics of different ages with emphasis on basalts, and have recognized secular changes, especially at the Archean Proterozoic (A&’) boundary. Others have focused on granitoids associated with greenstones, and have reported secular geochemical changes, again with the most prominent changes at the A/P boundary.
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.
