A sustained + 21m sea-level highstand during MIS 11 (400 ka)
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Material Information

Title:
A sustained + 21m sea-level highstand during MIS 11 (400 ka) direct fossil and sedimentary evidence from Bermuda
Series Title:
Quaternary Science Reviews Numbe 28
Creator:
Olson, Storrs L.
Hearty, Paul J.
Affiliation:
A sustained 21m sealevel highstand during MS 11 (400 ka): directfossil and sedimentgary evidence from Bermuda
Publisher:
Elsevier
Publication Date:
Language:
English

Subjects

Subjects / Keywords:
Climate Change ( lcsh )
Global Warming ( lcsh )
Sea Level Rise ( lcsh )
Bermda isalnds ( lcsh )

Notes

Abstract:
A small, protected karstic feature exposed in a limestone quarry in Bermuda preserved abundant sedimentary and biogenic materials documenting a transgressive phase, still-stand, and regressive phase of a sea-level in excess of 21.3 m above present during Marine Isotope Stage (MIS) 11 (400 ka) as determined by U/Th dating and amino acid racemization. Cobbles and marine sediments deposited during the high-energy transgressive phase exhibit rim cements indicating a subsequent phreatic environment. This was succeeded stratigraphically by a still-stand deposition of fine calcareous lagoonal sediments containing bioclasts of red algae and benthic and planktonic foraminifera that was intensely burrowed by marine invertebrates, probably upogebiid shrimp, that could not be produced under any condition other than sustained marine submergence. Overlying this were pure carbonate beach sands of a low-energy regressive phase containing abundant remains of terrestrial and marine vertebrates and invertebrates. The considerable diversity of this fauna along with taphonomic evidence from seabird remains indicates deposition by high run-up waves over a minimum duration of months, if not years. The maximum duration has yet to be determined but probably did not exceed one or two thousand years. The most abundant snails in this fauna are two species indicative of brackish water and high-tide line showing that a Ghyben-Herzberg lens must have existed at > þ 20 m. The nature of these sediments and fossil accumulation is incompatible with tsunami deposition and, given the absence of evidence for tectonic uplift of the Bermuda pedestal or platform, provide proof that sea-level during MIS 11 exceeded þ20 m, a fact that has widespread ramifications for geologists, biogeographers, and human demographics along the world’s coastlines. ( English )

Record Information

Source Institution:
Florida Intertatiional University
Rights Management:
Please contact the owning institution for licensing and permissions. It is the user's responsibility to ensure use does not violate any third party rights.
Resource Identifier:
:10.1016/j.quascirev.2008.11.001 ( doi )

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Aggregations:
Sea Level Rise