Lithological responses to sea erosion along selected coastlines between Komenda and Saltpond, Ghana

Abstract

Understanding the processes of coastal erosion calls for several methods to assess its extent and impact. Geomorphological investigation into coastal erosion is based on the shape and size of particles. Its importance is manifested in its ability to interpret past and recent geological forms and processes and to envision paleogeographical environments. This study examined how the lithological makeup of the coastline responds to erosion. It focused on the coastline between Gold Hill (Komenda) and Amisano (Saltpond) in the Central Region of Ghana. Cailleaux’s Indices of Roundness and Flatness were used to ascertain the responses of lithology to erosion along the coastline.  

Abrasion and attrition were the major erosional processes that left evidence for observation. Through these processes, the characteristic behaviour of rock types was established. It was observed that the roundness of schist is short-lived although it is attained quickly, while quartzite sustains its roundness for a longer time. Though the same erosional processes prevail, the shoreline retreats at different rates due to differences in lithology.