Marine bio-erosion cavities in metamorphic limestone, weathering rates, and the post glacial land rise in Salten, North Norway.

Abstract

Marine mollusk activity initiate erosion cavities in marble and dolomite in the Saltsraumen littoral zone. Such cavities are gradually exposed above sea water by the still on-going eustatic rebound since the last Ice age. The diameter of cavities observed above the high tide zone plotted against altitude show a steady increase in size over time due to weathering processes. Weathering rates as a function of land rise are calculated and discussed. The observed growth rates are correlated with chronology of sea level changes in the same period based on alternative data.