Geological characteristics of 2011 Japan tsunami sediments deposited along the coast of southwestern Mexico.

Abstract: The tsunami of 11th March 2011 was originated at the east coast of Japan and deposited ca.1cm thick sediment layer along the coast of southwestern Mexico up to a maximum distance of 320m from the beach. The sedimentological, mineralogical and geochemical characteristics of the sediments deposited during the tsunami (JT) are compared with the pre-tsunami sediments (PRT). JT sediments consist of dominant coarser fractions (>54% of medium to coarse sand), whereas PRT deposits comprise abundant finer fractions (>58% of fine sand). Assemblage of mafic and heavy minerals suggests similar provenance for both. The higher abundance and variation of heavy minerals along with higher concentrations of bromine (Br) and sodium (Na) in the JT deposits reveal the influence of high energy sea waves in transportation of heavy mineral rich coarse sediments onto the coastal lowlands. [Copyright &y& Elsevier]