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

A mantle plume origin for the Palaeoproterozoic Circum-Superior Large Igneous Province

Ciborowski, Jake, Minifie, M J, Kerr, Andrew Craig, Ernst, R.E. and Baragar, B. 2017. A mantle plume origin for the Palaeoproterozoic Circum-Superior Large Igneous Province. Precambrian Research 294 , pp. 189-213. 10.1016/j.precamres.2017.03.001

[img]
Preview
PDF - Published Version
Available under License Creative Commons Attribution.

Download (5MB) | Preview

Abstract

The Circum-Superior Large Igneous Province (LIP) consists predominantly of ultramafic-mafic lavas and sills with minor felsic components, distributed as various segments along the margins of the Superior Province craton. Ultramafic-mafic dykes and carbonatite complexes of the LIP also intrude the more central parts of the craton. Most of this magmatism occurred ∼1880 Ma. Previously a wide range of models have been proposed for the different segments of the CSLIP with the upper mantle as the source of magmatism. New major and trace element and Nd-Hf isotopic data reveal that the segments of the CSLIP can be treated as a single entity formed in a single tectonomagmatic environment. In contrast to most previous studies that have proposed a variety of geodynamic settings, the CSLIP is interpreted to have formed from a single mantle plume. Such an origin is consistent with the high MgO and Ni contents of the magmatic rocks, trace element signatures that similar to oceanic-plateaus and ocean island basalts and εNd-εHf isotopic signatures which are each more negative than those of the estimated depleted upper mantle at ∼1880 Ma. Further support for a mantle plume origin comes from calculated high degrees of partial melting, mantle potential temperatures significantly greater than estimated ambient Proterozoic mantle and the presence of a radiating dyke swarm. The location of most of the magmatic rocks along the Superior Province margins probably represents the deflection of plume material by the thick cratonic keel towards regions of thinner lithosphere at the craton margins. The primary magmas, generated by melting of the heterogeneous plume head, fractionated in magma chambers within the crust, and assimilated varying amounts of crustal material in the process.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Earth and Ocean Sciences
Subjects: Q Science > QE Geology
Publisher: Elsevier
ISSN: 0301-9268
Funders: Natural Environmental Research Council (NERC)
Date of First Compliant Deposit: 7 March 2017
Date of Acceptance: 5 March 2017
Last Modified: 24 Feb 2019 23:45
URI: http://orca.cf.ac.uk/id/eprint/98753

Citation Data

Cited 3 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