Age and geochemistry of igneous rocks in the Guatemalan forearc: Implications for the early history of the Caribbean Large Igneous Province

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It is widely accepted that Large Igneous Provinces are formed through catastrophic magmatic events producing widespread volcanic plateaus within a relatively short period of time. One of the best-known examples is the Caribbean Large Igneous Province (CLIP). Recent geochronological and geochemical studies, however suggest that the CLIP represents an amalgamation of several smaller oceanic plateaus formed over long periods of time by multiple pulses of the Galápagos plume head. The vast ophiolitic basement beneath the Guatemalan forearc discovered and sampled during DSDP legs 67 and 84 could possibly represent an earlier part of such an oceanic plateau. We propose detailed geochronological, petrologic and geochemical investigations of samples from the drilling to confirm the possible affiliation of the 1000 km long forearc basement with the CLIP. The proposed study will not only expand our understanding of the temporal and geotectonic history of Central America, but also our knowledge of the age and composition of Large Igneous Provinces. A better understandig of how these provinces formed will allow us to better assess their impact on the past global enviroment and life on this planet.