Secular Geochemistry of Central Puerto Rican Island Arc Lavas: Constraints on Mesozoic Tectonism in the Eastern Greater Antilles

Island arc volcanism in the Greater Antilles persisted for >70 m.y. from Middle Cretaceous to Late Eocene time. During the initial 50 m.y., lavas in central Puerto Rico shifted from predominantly island arc tholeiites (volcanic phase I, Aptian to Early Albian, 120–105 Ma), to calc-alkaline basalts (phase II, Late Albian, 105–97 Ma), and finally to high-K, incompatible-element-enriched basalts (phases III and IV, Cenomanian–Maastrichtian, 97–70 …