STRATHKINNESS: THE LAST GLACIATION AND ITS AFTERMATH

Alan Werritty has written about the last ice age and its effect on

Strathkinness.

Eighteen thousand years ago the site of Strathkinness was submerged

beneath hundreds of metres of glacial ice. This was part of the last great

icesheet which covered Scotland during the period known as the Ice Age.

This final icesheet originated in the Highlands and moved eastwards over

Strathkinness some 25,000 years ago. By 18,000 years ago it had reached

its maximum extent which meant that the whole of Fife was beneath the

icesheet with only the summit of West Lomond Hill possibly emerging as an

isolated rocky summit. At this stage the icesheet terminated some 40 kilo-

metres to the east of Fifeness. Over the next four thousand years the icesheet

steadily decayed with the edge of the ice moving westwards across Fife once

again exposing the landsurface to the atmosphere and to colonisation by

plants and animals.

The movement and melting of this large volume of ice was to have a pro-

found effect on the relief (contrast in surfaces) of the area immediately around

Strathkinness. Glacial ice is a very powerful erosive agent which can scour

away the less resistant rock leaving more resistant areas as relatively high

ground. Thus the resistant dolerite dyke which outcrops in the sandstone

beneath Strathkinness is largely responsible for the ridge upon which the village

is located. Once the ice melted the underlying bedrock was mantled (covered)

by deposits collectively known as drift. Two types of drift can be found in the

vicinity of Strathkinness: till and outwash. Till comprises poorly sorted

angular material enclosed in a finer clay and represents the direct result of an

icesheet moving across the landsurface. Many of the low hills near the village

are covered by till. Outwash on the other hand, is reworked material which has

been transported by streams issuing from a decaying icesheet, As a result out-

wash tends to be rather sandy and gravelly in composition. Outwash deposits

are more common to the north of the village in the vicinity of Kincaple.

The other important impact of the last icesheet was its effect on local sea-

levels. During a period when icesheets are being built up sea-levels fall as

water is removed from the ocean basins. Conversely, when icesheets melt

sea-levels rise. The land surface also undergoes vertical movement since it is

depressed when an icesheet develops and returns to its normal level when that

icesheet melts. The combination of these changes on the relative positions of

the land and sea means that sea-levels close to Strathkinness have changed

dramatically. Thus 15,000 years ago sea-level stood at roughly 100 feet above

the present level and a beach was cut into the bedrock near Strathtyrum. By

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