The Role of Sea Spray in Vadose Diagenesis in Late Quaternary Coastal Deposits


  • Sue J. McLaren


Processes, carbonate vadose diagenesis, sea spray.


A total of 162 samples from a range of aeolianites and raised beach deposits from Mallorca in the Mediterranean, Jamaica and the Bahamas, were studied to examine the effects of sea spray on early carbonate diagenesis. Those sediments that were more affected by sea spray consistently showed greater diagenetic alteration. Exposure to sea spray resulted in greater dissolution of the allochems creating high levels of secondary porosity. It is likely that this was brought about by mixing corrosion. In addition, deposits exposed to sea spray tended to be better cemented owing to the enhanced supply of CaCO3, predominantly from the dissolution of the allochems. Direct precipitation from sea water is a minor contribution of calcium carbonate for cement. The geochemistry of the cements, low in Mg2+ and Sr2+, and with a few high-Mg calcite and dolomite crystals, is consistent with the relative importance of these two sources.