The Post-Glacial Deposits of the Lincolnshire Coast

Abstract

Between the Lincolnshire Wolds and the coast there lies a narrow belt of low-lying land usually referred to as the Lincolnshire marsh. Within this belt two types of scenery exist. The one, founded on boulder-clay, is characterized by a well-wooded hummocky surface. It occupies a continuous strip of country along the foot of the wolds (Pl. XXX), but its seaward margin is irregularly indented and has outlying patches standing up like large mounds in the marshland proper. The latter constitutes the second type of country. It is flat and almost treeless, and is made up of stiff clays mainly of estuarine origin. The process of building up this marshland is still going on along the coast north of Mablethorpe and south of Skegness. The first-mentioned portion of the coast lies under the lee of Spurn Point, the latter lies within the shelter of the Wash, where extensive salt marshes exist. Between Mablethorpe and Skegness the coast is being slowly eroded. This fact is disguised by the absence of cliffs and the presence of an almost continuous covering of sand which hides the outcrops of the marshland clays. Owing to the action of the waves and currents, this sheet of sand as it drifts southwards becomes broken by valley-like hollows, often more than a mile long, which extend obliquely across the beach. These hollows are scoured by strong and dangerous currents which sweep away the sand and both expose and erode the clays beneath. They offer the only natural and, at