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Large igneous provinces
chapterposted on 2023-05-22, 23:07 authored by Mike CoffinMike Coffin, Eldholm, O
Large igneous provinces (LIPs) are massive crustal emplacements of predominantly iron- and magnesium-rich (mafic) rock that form by processes other than normal seafloor spreading; they are the dominant form of near-surface magmatism on the terrestrial planets and moons of our solar system. On the Earth’s surface, LIP rocks are readily distinguishable from the products of the two other major types of magmatism – mid-ocean ridge magmatism and arc magmatism – on the basis of petrologic, geochemical, geochronological, geophysical, and physical volcanological data. LIPs occur both on the continents and in the oceans, and include continental flood basalts, volcanic divergent margins, oceanic plateaus, submarine ridges, seamount chains, and ocean-basin flood basalts (Figure 1 and Table 1). LIPs and their contemporary small-scale analogues, hotspot volcanoes, are commonly attributed to decompression melting of hot low-density mantle material ascending from the Earth’s interior in mantle plumes, and thus provide a window into mantle processes. This type of magmatism currently accounts for about 10% of the mass and energy flux from the Earth’s deep interior to its crust. The flux may have been higher in the past, but is episodic over geological time, in contrast to the relatively steady-state activity at seafloor spreading centres and subduction zones. Such episodicity reveals dynamic non-steadystate circulation within the Earth’s mantle, perhaps extending far back into Earth history, and suggests a strong potential for LIP emplacements to contribute to, if not instigate, major environmental changes.
Publication titleReference Module in Earth Systems and Environmental Sciences
Department/SchoolInstitute for Marine and Antarctic Studies
Place of publicationUSA
Rights statementCopyright 2014 Elsevier, Inc.