This paper describes the effect of periglacial processes on that part of the Lincoln Scarp which is to be crossed by the Lincoln Relief Road. The scarp crest has been extensively modified with the development of small cambered blocks and major gulls parallel to the principal joint direction in the Lincolnshire Limestone. Geophysical investigation has revealed a marked increase in seismic velocity of the basal units of limestone as the degree of alteration decreases down dip (1855 m sec-1 near the crest and 5000 m sec-1 300 metres down dip). Electrical conductivity techniques have proved successful in the location of gulls.
Upper Lias clays, which form the scarp, are covered by solifluction deposits and both materials have been affected by processes interpreted as periglacial mass wasting. Relic planar slides associated with the mass wasting have been reactivated during periods of high seepage rates from the Limestone and underlying Northampton Sandstone units. Accurate topographic profiles have been used to determine the nature of complex, shallow rotational slide failures on the upper slopes of the scarp.
- © 1983 The Geological Society