Superstorms: Comments on Bahamian Fenestrae and Boulder Evidence from the Last Interglacial

Abstract

ABSTRACT Mylroie, J.E., 2018. Superstorms: Comments on Bahamian fenestrae and boulder evidence from the Last Interglacial. Sea level during the last interglacial (Marine Isotope Substage 5e [MIS 5e]) was ∼6 m above present, interpreted to represent a warmer climate, with increased storm intensity and storm frequency. Two hypotheses have been advanced to demonstrate an increase in storm intensity during MIS 5e. The first considers fenestrae in eolian calcarenites at elevations up to 43 m in the Bahama Archipelago to be evidence of superstorm washover. Additional observations include rip-up clasts and loss of bedform and root structures as a result of wave scour. Such an event should produce a tempestite with a wide-ranging footprint, but none exists above 10 m. This paper argues that the fenestrae are rainfall slurries, rip-up clasts are weathering products of calcarenite protosol development, and bed-form and root structure absence or presence reflects transgressive-phase vs. regressive-phase eolian forma...