Atlantic Gulfs, Estuaries, and Cliffs

Publisher Website
Google Scholar
Abstract
The morvan theory with slight modification fits the structure of the coasts of south-western Britain better than the fault theory of Atlantic coasts advanced by Suess.The English Channel and St. George's Channel have been long in existence, and are more probably of tectonic than erosional origin.Erosional deepening of the valleys which were drowned by the Flandrian transgression to become estuaries must have taken place almost entirely in glacial ages when the level of the ocean has been low. The tempo of coastal erosion, both subaerial and marine, has been rather slow, however, owing to the great width of the continental shelf. Thus shoreline details survive from an interglacial age.In regions with a narrower continental shelf, deepening and also extensive enlargement of valleys across coastal lands have taken place in each glacial age of low ocean level, and interglacial aggradations have determined terrace levels at consistent heights in the inland valleys of large rivers, as exemplified in Portugal.The cliffs of Cornwall and Wales show traces of two cycles or marine retrogradation separated by a withdrawal of the sea. Thus the “bevel”, or “coastal slope” above modem cliffs can be accounted for as an ancient sea-cliff graded subaerially during the period of low ocean level.

This publication has 19 references indexed in Scilit: