The onset of the North Atlantic Igneous Province in a rifting perspective

• Published in: Geological magazine 2009-05, Vol.146 (3), p.309-325
• Main Authors: HANSEN, J., JERRAM, D. A., McCAFFREY, K., PASSEY, S. R.
• Format: Article
• Language: English
• Subjects: Arctic Ocean; Arctic region; Atlantic Ocean; Atlantic Ocean Islands; Baffin Island; basalts; Caledonides; Canada; Cenozoic; continental drift; Eastern Canada; Eocene; Europe; Faeroe Islands; flood basalts; Geochemistry; geometry; Geophysics; Great Britain; Greenland; hot spots; Iapetus; igneous and metamorphic rocks; Igneous rocks; large igneous provinces; Lava; Lithosphere; lower Eocene; Magma; magmas; magmatism; mantle; mantle plumes; North Atlantic; North Atlantic igneous province; Norwegian Sea; Nunavut; ocean basins; orogenic belts; orogenic sutures; orogeny; Paleocene; Paleogene; paleogeography; petrology; Plate tectonics; rift zones; Rifting; Scotland; Seismology; Shetland Islands; solid Earth (tectonophysics); suture zones; tectonics; Tertiary; triple junctions; United Kingdom; upper mantle; volcanic rocks; volcanism; Volcanoes; Voring Basin; West Greenland; Western Europe
• ISSN: 0016-7568; 1469-5081
• DOI: 10.1017/S0016756809006347

The processes that led to the onset and evolution of the North Atlantic Igneous Province (NAIP) have been a theme of debate in the past decades. A popular theory has been that the impingement on the lower lithosphere of a hot mantle plume (the ‘Ancestral Iceland’ plume) initiated the first voluminous outbursts of lava and initiated rifting in the North Atlantic area in Early Palaeogene times. Here we review previous studies in order to set the NAIP magmatism in a time–space context. We suggest that global plate reorganizations and lithospheric extension across old orogenic fronts and/or suture zones, aided by other processes in the mantle (e.g. local or regional scale upwellings prior to and during the final Early Eocene rifting), played a role in the generation of the igneous products recorded in the NAIP for this period. These events gave rise to the extensive Paleocene and Eocene igneous rocks in W Greenland, NW Britain and at the conjugate E Greenland–NW European margins. Many of the relatively large magmatic centres of the NAIP were associated with transient and geographically confined doming in Early Paleocene times prior to the final break-up of the North Atlantic area.