Seamounts as Sea-Level Indicators

Abstract

Terraces on Cobb and Bowie Seamounts, with shelf breaks at 120 and 140 fms, respectively, are believed to have been wave cut during the Pleistocene. Terrace bathymetry plus polished and rounded pebbles obtained in grab samples from these terraces support a wave abrasion genesis. As the Seamounts were formed during the Cenozoic the continually descending lows of sea-level fluctuations through the Tertiary and Quaternary would suggest a late Pleistocene origin for both of the terraces. Upon consideration of possible hypotheses for the virtual doubling of the presently known 130-m Wisconsin low, it would seem that there are more factors involved in sea-level changes than have been considered heretofore. The reality of a 120- to 140-fm sea-level low during the late Wisconsin should not, at this time, be rejected out of hand.