Abstract
Marine inundation associated with the 5 to 8 m storm surge of Typhoon Haiyan in 2013 left overwash sediments inland on the coastal plains of the northwestern shores of Leyte Gulf, Philippines. The Haiyan overwash deposit provides a modern sedimentary record of storm surge deposition from a Category 5 landfalling typhoon. We studied overwash sediments at two locations that experienced similar storm surge conditions but represent contrasting sedimentological regimes, namely a siliciclastic coast and a mixed siliciclastic-carbonate coast. The contrasting local geology is significantly reflected in the differences in sediment grain size, composition and sorting at the two sites. The Haiyan overwash sediments are predominantly sand and silt and can be traced up to similar to 1.6 km inland, extending farther beyond the previously reported <300 m="" inland="" limit="" of="" sedimentation.="" sites="" with="" similar="" geology,="" topographic="" relief,="" and="" overland="" flow="" conditions="" show="" significant="" spatial="" variability="" of="" sediment="" thickness="" and="" inland="" extent.="" we="" infer="" that="" other="" local="" factors="" such="" as="" small-scale="" variations="" in="" topography="" and="" the="" type="" of="" vegetation="" cover="" might="" influence="" the="" spatial="" distribution="" of="" overwash="" sediments.="" the="" haiyan="" overwash="" deposits="" exhibit="" planar="" stratification,="" a="" coarsening="" upward="" sequence,="" a="" non-systematic="" landward="" fining="" trend,="" and="" a="" sharp="" depositional="" (rarely="" erosional)="" basal="" contact="" with="" the="" underlying="" substrate.="" overall,="" the="" haiyan="" deposits="" have="" sedimentologic="" and="" stratigraphic="" characteristics="" that="" show="" a="" hybrid="" signature="" common="" to="" both="" storm="" and="" tsunami="">