Abstract
The globe-encircling isotopic anomaly centred on latitude 30°S defined from the geochemistry of mid-ocean ridge and particularly intraplate basalts has been previously shown to be correlative with degree-2 features of the Earth's geoid. The same region appears to show a correlation with zones of low seismic velocities, perhaps indicative of heated rocks, which persist to at least the transition zone between the upper and lower mantle. That the basalts in this anomalous region are derived by diapiric uprise from a mantle reservoir of old deeply subducted materials is favourably demonstrated by olivine and clinopyroxene-controlled partial melting trends on geochemical discrimination diagrams.
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.
