Evolution of North Malé Atoll Rim during the Last Full Glacial Cycle (Malé Island, Republic of Maldives)
Droxler, André W
Master of Science
My study focuses on the evolution of Malé Island to elucidate the late Pleistocene-Holocene evolution of the discontinuous North Malé Atoll rim. Sample analyses from two boreholes, published information from additional boreholes, and a multi-beam bathymetric map for Malé Island deep surroundings, are available for this study. Facies analyses of the lower sedimentary unit reveal an overall deepening coralgal reef that accumulated probably during the previous interglacial and subsequently was altered by meteoric diagenesis during a 100 ky-long exposure. The upper Holocene unconsolidated coralgal reef, overlying the karstified coralgal MIS 5e lower unit, was initiated at ~8200 kyr BP and vertically grew 25 m high until 6510 kyr BP, protected behind a karstified late Pleistocene reef. A small, though 30-35 m deep, newly formed lagoon started to fill up only at ~5500 kyr BP, when a reef initiated on top of the highest elevated Pleistocene karstified reef and sea level rise stalled.