The petrogenesis of Carboniferous–Permian dyke and sill intrusions across northern Europe

The presence or absence of a thermally anomalous mantle plume during the formation of the widespread Carboniferous–Permian magmatism of northern Europe is examined. The geochemistry of representative samples from the extensive Carboniferous–Permian dyke and sill intrusions across northern Europe are reported in order to ascertain whether they have a common ‘plume’ source. Both tholeiitic and alkaline magmas have diverse trace element compositions. Alkaline samples with relatively low Ti and Nb/La < 1 are considered to originate in the lithospheric mantle and those with Nb/La > 1 from the asthenosphere. The tholeiites have a close affinity to E-MORB but have mixed with variable amounts of lithosphere and upper crust. Tectonic reorganisation and decompression melting of a trace element-enriched mantle is considered to have controlled the Carboniferous–Permian magmatism, which contains no coherent geochemical evidence for a single plume-related thermo-chemical anomaly.