Abstract
Sm Nd isotopic data indicate that differential REE mobility occurred on a whole-rock scale during transitional amphibolite- to granulite-facies regional metamorphism (∼ 700°C, 7 kbar) in early Archaean rocks (∼ 3930 Ma) of the Napier Complex of Enderby Land, Antarctica. The degree of mobility is independent of metamorphic grade but correlates directly with development of tectonic fabric. Whole-rock samples with D 3-M 3 internal fabrics lie along an array corresponding to an age of 2410 ± 100Ma, whereas samples preserving only earlier fabrics preserve an older, albeit imprecisely defined isochron age. In contrast to a widely held belief, such changes did not require the presence of a large hydrous fluid flux. If the mechanism responsible for Sm Nd resetting at this locality (where T CHUR ages range from 1990 Ma to 6090 Ma) is more widespread than is currently recognised, isolated Sm Nd model ages, particularly in complex terrains should be treated with caution.
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.
