Toward a New Paradigm for Boulder Dislodgement during Storms

Boulders are an important coastal hazard event deposit because they can only be moved by tsunamis and storms. However, storms and tsunami are competing processes for coastal change along many shorelines. Therefore, distinguishing the boulders that were moved during a storm from those moved by a tsunami is important. In this contribution, we present the results of a parameter study based on the TRIADS model coupled with a boulder dislodgement model that is based on Newton's Second Law of Motion. The results show how smaller slopes expose the waves longer to the nonlinear processes that cause the transformation of energy into the infragravity wave band causing largerboulders to be dislodged more often than on steeper slopes.