Reply to “Mega-highstand or megatsunami? Discussion of McMurtry et al. “Elevated marine deposits in Bermuda record a late Quaternary megatsunami”: Sed. Geol. 200 (2007) 155–165” by Paul J. Hearty and Storrs L. Olson

• Published in: Sedimentary geology 2008-01, Vol.203 (3), p.313-319
• Main Authors: McMurtry, Gary M., Tappin, David R., Sedwick, Peter N., Wilkinson, Ian, Fietzke, Jan, Sellwood, Bruce
• Format: Article
• Language: English
• ISSN: 0037-0738
• DOI: 10.1016/j.sedgeo.2007.11.008

Our recent paper [McMurtry, G.M., Tappin, D.R., Sedwick, P.N., Wilkinson, I., Fietzke, J. and Sellwood, B., 2007a. Elevated marine deposits in Bermuda record a late Quaternary megatsunami. Sedimentary Geol. 200, 155–165.] critically re-examined elevated marine deposits in Bermuda, and concluded that their geological setting, sedimentary relations, micropetrography and microfaunal assemblages were inconsistent with sustained intertidal deposition. Instead, we hypothesized that these deposits were the result of a large tsunami that impacted the Bermuda island platform during the mid-Pleistocene. Hearty and Olson [Hearty, P.J., and Olson, S.L., in press. Mega-highstand or megatsunami? Discussion of McMurtry et al. “Elevated marine deposits in Bermuda record a late Quaternary megatsunami”: Sedimentary Geology, 200, 155–165, 2007 (Aug. 07). Sedimentary Geol. 200, 155–165.] in their response, attempt to refute our conclusions and claim the deposits to be the result of a +21 m eustatic sea level highstand during marine isotope stage (MIS) 11. In our reply we answer the issues raised by Hearty and Olson [Hearty, P.J., and Olson, S.L., in press. Mega-highstand or megatsunami? Discussion of McMurtry et al. “Elevated marine deposits in Bermuda record a late Quaternary megatsunami”: Sedimentary Geology, 200, 155–165, 2007 (Aug. 07). Sedimentary Geol. 200, 155–165.] and conclude that the Bermuda deposits do not provide unequivocal evidence of a prolonged + 21 m eustatic sea level highstand. Rather, the sediments are more likely the result of a past megatsunami in the North Atlantic basin.