The Avalon of Newfoundland: Geomorphology, People and Landscape

Abstract

The geomorphology of the Avalon Peninsula in easternmost Newfoundland is dominated by Ediacaran geology and lithology, local glaciation, and coastal processes developed under a boreal climate. The physiography, particularly the configuration of headlands and embayments, is closely related to the region’s tectonic history and structural geology. Repeated glaciation has resulted in landscapes dominated by bedrock erosional features. During MIS 2, numerous local ice caps developed during three phases, and expanded to cover the peninsula. To the west, ice from the main part of Newfoundland flowed into Placentia and Trinity Bays. Deglaciation was triggered by relative sea level rise in St. Mary’s Bay c. 14 ka, and was complete by 10 ka. At present, relative sea level is rising c. 3.5 mm/y, primarily as a result of residual glaci-isostatic subsidence. Most shorelines along the Avalon are distinguished by deep indentations open to either the southwest or northeast, aligned parallel to prevailing storm tracks, and steeply sloping nearshore bathymetry. The frequent storm activity, long fetch, and ambient moderate to high energy, in combination with the coastal configurations, produces shorelines dominated by swash activity, shore-normal transport and reflective conditions. A succession of residents has interacted with the geomorphology and landscape since the early Holocene.