A tsunami deposit (the term tsunamiite is also sometimes used) is a sedimentary unit deposited as the result of a tsunami. Such deposits may be left onshore during the inundation phase or offshore during the 'backwash' phase. Such deposits are used to identify past tsunami events and thereby better constrain estimates of both earthquake and tsunami hazards. There remain considerable problems, however, in distinguishing between deposits caused by tsunamis and those caused by storms or other sedimentary processes.