Monsoonal and fertility controls on Recent marginal sea and continental shelf coccolith assemblages from the western Pacific and northern Indian oceans

Abstract

Gephyrocapsa oceanica is often overwhelmingly dominant in coccolith assemblages found in monsoonal regions, including the marginal seas of the western Pacific and the more open seas and continental shelf of the northern Indian Ocean. The dominance of G. oceanica is thought to reflect its preference for elevated nutrient levels and a tolerance of lithogenic particles. Emiliania huxleyi is subordinate in assemblages deposited in monsoonal regions. Coccolith assemblages with dominant E. huxleyi are restricted to marginal seas with lagoonal (anti-estuarine) circulation (e.g. Red Sea) and open seas and continental shelves with strong oceanic influences, but no monsoonal effects (e.g. southern Great Barrier Reef, Coral Sea and Great Australian Bight).