Monsoon-induced partial carbonate platform drowning (Maldives, Indian Ocean)
- Christian Betzler1,
- Christian Hübscher2,
- Sebastian Lindhorst1,
- John J.G. Reijmer3,
- Miriam Römer1,*,
- André W. Droxler4,
- Jörn Fürstenau1 and
- Thomas Lüdmann5
- 1Geologisch-Paläontologisches Institut, Universität Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
- 2Institut für Geophysik, Universität Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
- 3Department of Sedimentology and Marine Geology, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, Netherlands
- 4Department of Earth Science MS-126, Rice University, P.O. Box 1892, Houston, Texas 77251-1892, USA
- 5Institut für Biogeochemie und Meereschemie, Universität Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
Abstract
Multibeam maps and high-resolution seismic images from the Maldives reveal that a late Miocene to early Pliocene partial drowning of the platform was linked to strong sea-bottom currents. In the upper Miocene to Holocene, currents shaped the drowned banks, the current moats along the bank edges, and the submarine dune fields. Bottom currents in the Maldives are driven by the monsoon. It is proposed that the onset and the intensification of the monsoon during the Neogene provoked platform drowning through injection of nutrients into surface waters. Since the late Miocene, topographically triggered nutrient upwelling and vigorous currents switched the Maldives atolls into an aggradational to backstepping mode, which is a growth pattern usually attributed to episodes of rising sea level.
-
- Received 25 November 2008.
- Revision received 22 April 2009.
- Accepted 4 May 2009.
- © 2009 Geological Society of America
