Holocene reef growth in the Maldives: Evidence of a mid-Holocene sea-level highstand in the central Indian Ocean

Abstract

Research Article| May 01, 2009 Holocene reef growth in the Maldives: Evidence of a mid-Holocene sea-level highstand in the central Indian Ocean P.S. Kench; P.S. Kench 11School of Geography, Geology and Environmental Science, University of Auckland, Private Bag 92019, Auckland, New Zealand Search for other works by this author on: GSW Google Scholar S.G. Smithers; S.G. Smithers 22School of Earth and Environmental Sciences, James Cook University, Townsville, QLD 4811, Australia Search for other works by this author on: GSW Google Scholar R.F. McLean; R.F. McLean 33School of Physical, Environmental and Mathematical Sciences, University of New South Wales, ACT 2600, Australia Search for other works by this author on: GSW Google Scholar S.L. Nichol S.L. Nichol 11School of Geography, Geology and Environmental Science, University of Auckland, Private Bag 92019, Auckland, New Zealand Search for other works by this author on: GSW Google Scholar Author and Article Information P.S. Kench 11School of Geography, Geology and Environmental Science, University of Auckland, Private Bag 92019, Auckland, New Zealand S.G. Smithers 22School of Earth and Environmental Sciences, James Cook University, Townsville, QLD 4811, Australia R.F. McLean 33School of Physical, Environmental and Mathematical Sciences, University of New South Wales, ACT 2600, Australia S.L. Nichol 11School of Geography, Geology and Environmental Science, University of Auckland, Private Bag 92019, Auckland, New Zealand Publisher: Geological Society of America Received: 10 Oct 2008 Revision Received: 18 Dec 2008 Accepted: 28 Dec 2008 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2009 Geological Society of America Geology (2009) 37 (5): 455–458. https://doi.org/10.1130/G25590A.1 Article history Received: 10 Oct 2008 Revision Received: 18 Dec 2008 Accepted: 28 Dec 2008 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation P.S. Kench, S.G. Smithers, R.F. McLean, S.L. Nichol; Holocene reef growth in the Maldives: Evidence of a mid-Holocene sea-level highstand in the central Indian Ocean. Geology 2009;; 37 (5): 455–458. doi: https://doi.org/10.1130/G25590A.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Radiometrically calibrated ages from three reef cores are used to develop a Holocene reef growth chronostratigraphy and sea-level history in the Maldives, central Indian Ocean. Last interglacial reef (U-series age 122 ± 7 ka) was encountered at 14.1 m below mean sea level. An age of ca. 8100 calibrated (cal) yr B.P. immediately overlying this Pleistocene surface records the initiation of Holocene reef growth. Massive in situ corals occur throughout the cores and the consistency of the three age-depth plots indicate that the reef grew steadily between 8100 and 6500 cal yr B.P., and at a decreasing rate for the next 2 k.y. The position of modern sea level was first achieved ca. 4500 cal yr B.P. and sea level reached at least 0.50 ± 1 m higher from 4000 to 2100 cal yr B.P. before falling to present level. Emergent fossil microatolls provide evidence of this higher sea level. Results are significant to two long-standing issues relating to Maldivian sealevel history. First, the ambiguity of a late Holocene highstand has been resolved with clear evidence of its existence reported here. Second, the uncertainty of the regional pattern of sea-level change in the central Indian Ocean has been clarified, the Maldivian results broadly agreeing with island records in the eastern, rather than western Indian Ocean. Our results provide the first field evidence confirming geophysical model projections of a highstand 4–2 k.y. ago in the central Indian Ocean, though the observed level (+0.50 ± 0.1 m) is lower than that projected. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.