Enriched Grenvillian lithospheric mantle as a consequence of long-lived subduction beneath Laurentia
MetadataShow full item record
Geochemical and Nd isotopic data from mafic and newly discovered ultramafic rocks in the Adirondack Lowlands suggest widespread enrichment of the lithospheric mantle under the Grenville Province. Incompatible element abundances and previously published Hf TDM (zircon) (depleted mantle model age) and Nd TDM ages from rocks of the anorthosite-mangerite-charnockite-granite suite in the Adirondack Highlands document similar enrichment in the lower crust and its strong influence on subsequent magmatic events throughout the Ontario-Quebec-Adirondack segment of the Grenville Province. Likely the consequence of long-lived (ca. 1.4–1.2 Ga) northwest-directed subduction along the southeast edge of Laurentia (previously proposed Andean margin), this enrichment is similar to that associated with the vast (>240,000 km2) ultrapotassic province of the western Churchill Province. Enrichment of the lithospheric mantle beneath orogenic belts is a predictable and important differentiation process that has operated on Earth for at least the past 3 b.y.
Showing items related by title, author, creator and subject.
Constraints and deception in the isotopic record; The crustal evolution of the west Musgrave Province, central AustraliaKirkland, Chris; Smithies, R.; Woodhouse, A.; Howard, H.; Wingate, M.; Belousova, E.; Cliff, J.; Murphy, R.; Spaggiari, C. (2013)The Hf and Nd isotopic evolution of the Musgrave Province, central Australia, is used to constrain the timing of crust formation and lithospheric organisation of Proterozoic Australia. The dataset from this region challenges ...
Depleted Mantle-sourced CFB Magmatism in the Jurassic Africa–Antarctica Rift: Petrology and 40Ar/39Ar and U/Pb Chronology of the Vestfjella Dyke Swarm, Dronning Maud Land, AntarcticaLuttinen, A.; Heinonen, J.; Kurhila, M.; Jourdan, Fred; Mänttäri, I.; Vuori, S.; Huhma, H. (2015)The Jurassic Vestfjella dyke swarm at the volcanic rifted margin of western Dronning Maud Land represents magmatism related to the incipient Africa–Antarctica rift zone; that is, rift-assemblage magmatism of the Karoo ...
The Cambrian Kalkarindji Large Igneous Province: extent and characteristics based on new 40Ar/39Ar and geochemical dataEvins, L.Z.; Jourdan, Fred; Phillips, D. (2009)The Early Cambrian Kalkarindji Continental Flood Basalt Province in northern Australia is an important Large Igneous Province (LIP) both in size and timing. Being the earliest Phanerozoic LIP it may have had a severe ...