Geological
cross-section through the northern plain
Between
70,000-10,000 years ago the Isle of Man was covered by an ice sheet
which had spread out from the mountains of Scotland.
The ice is thought to have advanced and retreated over the Island
several times during this period. When the ice advanced for the
last time it pushed up a pile of soft sediment in front of it, similar
to a bulldozer, to form the Bride Hills. When the ice melted it
deposited material contained within it to form a veneer of glacial
sediment
now covering the northern plain. Some of this material includes
rock plucked from the mountains of Scotland and from the floor of
the Irish Sea and these can now be found as pebbles at the Point
of Ayre. Associated with the glacial deposits are outwash material
left by meltwater flowing as rivers southwards from the glacier
and alluvial fans composed of sediment washed down from the mountains
during summer thaws.
