Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Mantle dynamics of the Central Atlantic Magmatic Province (CAMP): Constraints from platinum group, gold and lithophile elements in flood basalts of Morocco

Tegner, Christian, Michelis, Sandra A T, McDonald, Iain ORCID: https://orcid.org/0000-0001-9066-7244, Brown, Eric L, Youbi, Nasrrddine, Callegaro, Sara, Lindström, Sofie and Marzoli, Andrea 2019. Mantle dynamics of the Central Atlantic Magmatic Province (CAMP): Constraints from platinum group, gold and lithophile elements in flood basalts of Morocco. Journal of Petrology , -. 10.1093/petrology/egz041

[thumbnail of Tegner et al 2019 J Petrology FINAL.pdf]
Preview
PDF - Accepted Post-Print Version
Download (6MB) | Preview

Abstract

Mantle melting dynamics of the Central Atlantic Magmatic Province (CAMP) are constrained from new platinum group element (PGE), rare earth element (REE), and high field strength element (HFSE) data and geochemical modelling of flood basalts in Morocco. The PGE are enriched similarly to flood basalts of other large igneous provinces. The magmas did not experience sulphide saturation during fractionation and were therefore fertile. The CAMP province is thus prospective for PGE and Gold mineralisation. The Pt/Pd ratio of the Moroccan lavas indicates that they originated by partial melting of the asthenospheric mantle, not the subcontinental lithospheric mantle. Mantle melting modelling of PGE, REE and HFSE suggests: (1) that the mantle source for all the lavas was dominated by primitive mantle and invariably included a small proportion of recycled continental crust (<8%); (2) the mantle potential temperature was moderately elevated (c. 1430 °C) relative to ambient mantle; (3) intra-lava unit compositional variations are likely a combined result of variable amounts of crust in the mantle source (heterogeneous source) and fractional crystallisation; (4) mantle melting initially took place at depths between c. 110 km and c. 55 km and became shallower with time (c. 110 km to c. 32 km depth); and (5) the melting region appears to have changed from triangular to columnar with time. These results are best explained by melting of asthenospheric mantle that was mixed with continental sediments during the assembly of Pangaea, then heated and further mixed by convection while insulated under the Pangaea supercontinent, and subsequently melted in multiple continental rift systems associated with the breakup of Pangaea. Most likely the CAMP volcanism was triggered by the arrival of a mantle plume, although plume material apparently was not contributing directly (chemically) to the magmas in Morocco, nor to many other areas of CAMP.

Item Type: Article
Date Type: Published Online
Status: Published
Schools: Earth and Environmental Sciences
Publisher: Oxford University Press (OUP): Policy B - Oxford Open Option A
ISSN: 0022-3530
Date of First Compliant Deposit: 17 September 2019
Date of Acceptance: 3 September 2019
Last Modified: 06 Nov 2023 23:54
URI: https://orca.cardiff.ac.uk/id/eprint/125505

Citation Data

Cited 19 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics