Petrogenic history of volcaniclastic carbonates from Curaçao, Netherlands Antilles

Abstract

Two formations on Curacao contain abundant volcaniclastic materials within a carbonate rock, the Neogene Seroe Domi formation, and the quaternary lower coral terrace. These two formations have clasts of Curacao lava formation of various sizes and degrees of diagenetic alteration. This study hypothesizes that the alteration of clasts of the Curacao lava formation liberates Mg ions into diagenetic fluids that contribute to: (1) the dolomitization of the Seroe Domi formation and/or (2) microbial precipitation of magnesium-rich carbonate mineral phases. Textural, petrographic, mineralogic, and elemental data indicate that the unaltered material of the lower terrace contains Mg-rich mineral phases that are missing in the older, altered Seroe Domi rocks. These results suggest that carbonate rocks with mafic detrital materials are possible environments for Mg enrichment that may lead to the formation of Mg-rich carbonate mineral phases.