Geochemical and Mineralogical Proxies for characterizing Tsunami and Paleotsunami Deposits

Abstract:

In this study we show how geochemistry and mineralogy can be used to correlate between previously dated tsunami and paleotsunami deposits in western Thailand. We do this based on cores from three parallel swales along a transect from the shoreline inland. Stratigraphy, together with geochemical and mineralogical analyses was used to correlate between tsunami and paleotsunami layers at these sites. Using element biplots (Ti-Zr, Ti-Y and Zr-Y) and mineralogical constraints, source signatures of each of the tsunami and paleotsunami layers were used to correlate between sand layers representing the 2004 tsunami and sand layers representing at least three paleotsunamis. Based on our correlations between these swales, we predict different inundation distances and directions for these paleotsunamis. Our study shows that a combination of geochemical and mineralogical analysis provides a powerful tool for correlation between tsunami and paleotsunami layers.