Secular Geochemistry of Central Puerto Rican Island Arc Lavas: Constraints on Mesozoic Tectonism in the Eastern Greater Antilles |
| |
Authors: | JOLLY WAYNE T; LIDIAK EDWARD G; DICKIN ALAN P; WU TSAI-WAY |
| |
Institution: | 1DEPARTMENT OF EARTH SCIENCES, BROCK UNIVERSITY, ST. CATHARINES, ONT., CANADA L2S 3A1
2DEPARTMENT OF GEOLOGY AND PLANETARY SCIENCES, UNIVERSITY OF PITTSBURGH, PITTSBURGH, PA 15260, USA
3DEPARTMENT OF GEOLOGY, McMASTER UNIVERSITY, HAMILTON, ONT., CANADA L8S 4M1
4DEPARTMENT OF GEOLOGY, UNIVERSITY OF WESTERN ONTARIO, LONDON, ONT., CANADA N6A 5B7 |
| |
Abstract: | Island arc volcanism in the Greater Antilles persisted for >70m.y. from Middle Cretaceous to Late Eocene time. During theinitial 50 m.y., lavas in central Puerto Rico shifted from predominantlyisland arc tholeiites (volcanic phase I, Aptian to Early Albian,120105 Ma), to calc-alkaline basalts (phase II, LateAlbian, 10597 Ma), and finally to high-K, incompatible-element-enrichedbasalts (phases III and IV, CenomanianMaastrichtian,9770 Ma). Following an island-wide eruptive hiatus, geochemicaltrends were reversed in the Eocene with renewed eruption ofcalc-alkaline basalts (phase V, 6045 Ma). Progressiveincreases in large-ion lithophile elements (LILE)/light rareearth elements (LREE), LILE/high field strength elements (HFSE),LREE/HFSE, and HFSE/heavy rare earth elements (HREE) characterizethe compositional evolution of the first four volcanic phases.The shift in trace element compositions is mirrored by increasingradiogenic content of the lavas. Pb |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|