Longshore sediment transport and a sediment for the Malpeque barrier system, southern Gulf of St. Lawrence

Abstract

Wave hindcasting and refraction techniques were used to establish inshore wave conditions and longshore sediment transport rates along a 43 km barrier island shoreline at Malpeque, Prince Edward Island, in the southern Gulf of St. Lawrence. Net longshore sediment transport is directed southeastwards, at rates varying from 40 000 m3 year−1 to greater than 200 000 m3 year−1. The information on longshore transport was combined with volumetric estimates of shore normal sedimentary exchanges to define the sediment budget of the barrier sands at Malpeque. The results of the budget analysis indicate that subtidal erosion in the shoreface zone is the principal source of sand for the longshore transport system.