Aspects of the Wolds landscape: valley heads and sliding hills

Author: Derek Gobbett.

We looked in some detail at School House Dale which is access land on the Sledmere estate. This dale is a typical dry valley near its head with symmetrical sides uniformly sloping at about 22°. There is an abrupt change in slope where the valley sides meet the flat floor. In parts of the dale there is a low terrace running along this junction. We walked along the top of the valley side noting signs of small landslips. A tributary valley meets the main valley at about 90° and hangs slightly above it. The long profiles of the tributary and the main valley are relatively steep. At the head of the dale a number of short steep gulleys coalesce.

We returned down the floor of the valley noticing signs of longitudinal bars now much degraded. The leader suggested that the features we had seen show that the valley was eroded by a  flashy braided stream with a gravel bedload, such as would flow in the summer under periglacial conditions with permafrost during the last, Devensian, ice age.

We then drove to North Grimston to lunch at the Middleton Arms or in the flower-carpeted Corallian limestone quarry on the hill above the village.

The afternoon comprised a walk from Settrington Beacon to look at features of the Wolds escarpment. Halfway between the beacon and Many Thorns Farm we stopped on the edge of the escarpment to take in the wide view across the Vale of Pickering to the Tabular and the Cleveland Hills to the north and northwest, the Howardian Hills to the west and southwards along the Wolds scarp. From Bassett Brow we could appreciate the broad re-entrant of the Wintringham Gap and the land-slipped nature of the Wolds escarpment. The disturbance of the chalk was briefly examined in a disused chalk pit before walking along the Stack Hills which are formed by deep rotational slips of chalk overlying clay. A fine view of these was obtained from the top of the escarpment before we returned to Settringham Beacon.

Stack Hills. Photograph: Dot Needham
Stack Hills.
Photograph: Dot Needham
Bassett Brow.  Photograph: Dot Needham
Bassett Brow.
Photograph: Dot Needham