Geochemistry of rare earth elements in basalts from Walvis Ridge ...

• Main Authors: Humphris, Susan E, Thompson, Geoffrey
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1983
• Subjects: Drilling/drill rig; Leg74; Leg75; Glomar Challenger; Deep Sea Drilling Project DSDP; South Atlantic Ocean
• Online Access: https://dx.doi.org/10.1594/pangaea.714985; https://doi.pangaea.de/10.1594/PANGAEA.714985

Selected basalts from a suite of dredged and drilled samples (IPOD sites 525, 527, 528 and 530) from the Walvis Ridge have been analysed to determine their rare earth element (REE) contents in order to investigate the origin and evolution of this major structural feature in the South Atlantic Ocean. All of the samples show a high degree of light rare earth element (LREE) enrichment, quite unlike the flat or depleted patterns normally observed for normal mid-ocean ridge basalts (MORBs). Basalts from Sites 527, 528 and 530 show REE patterns characterised by an arcuate shape and relatively low (Ce/Yb)N ratios (1.46-5.22), and the ratios show a positive linear relationship to Nb content. A different trend is exhibited by the dredged basalts and the basalts from Site 525, and their REE patterns have a fairly constant slope, and higher (Ce/Yb)N ratios (4.31-8.50).These differences are further reflected in the ratios of incompatible trace elements, which also indicate considerable variations within the groups. ... : Supplement to: Humphris, Susan E; Thompson, Geoffrey (1983): Geochemistry of rare earth elements in basalts from the Walvis Ridge: implications for its origin and evolution. Earth and Planetary Science Letters, 66, 223-242 ...