Investigating the birth and death of large igneous provinces

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Large igneous provinces (LIPs) consist of enormous emplacements of mafic extrusive and intrusive rocks, and they include such prominent features on Earth as continental flood basalts, oceanic plateaus, volcanic passive margins, submarine ridges, seamount chains, and perhaps some of the world's largest layered mafic-ultramafic intrusions. The major goals of the proposed field-petrologic-geochemical-isotopic-geochronologic research program address (1) how LIPs are initiated and how they are assembled, (2) how magmatism related to LIPs wanes and over what timeframe, and (3) whether two giant layered intrusions (Bushveld, Stillwater) represent the high-level cumulate reservoirs of LIPs? To address how LIPs are "born", the physical, chemical, and temporal architecture of the Triassic Karmusten flood basalts on Vancouver Island will be established to evaluate the mechanisms for assembly and growth of this immense accreted oceanic plateau. To address how LIPs "die", post-flood basalt intrusions from the Kerguelen Archipelago, a major oceanic island in the southern Indian Ocean, will be studied to determine what controls the origin and distribution of secondary magmatism, which occurs millions of years after the main magmatic activity ceases, in some LIPs. Given the very large volumes of basaltic magma produced over relatively short periods of geologic time, LIP magmatism represents a remarkably efficient process for the formation of basalt on Earth. The research program on these major large igneous provinces and layered intrusions will yield new samples, geochemical and geochronologic results, and interpretations that will significantly advance our knowledge of the internal evolution of these giant igneous bodies and the rates by which they form. The program will contribute directly to the training of 3 graduate and 3-4 undergraduate students, who will each be exposed to a wide range of research management, data analysis, and presentation skills that are in high demand from the mineral exploration industry, geological surveys, and research institutions worldwide.