In the last Ice Age there was an ice cap from which ice sheets
and glaciers travelled south, eroding huge amounts of material on
their way. This material was redeposited as till or boulder clay
across much of the lowlands of Northern England. When several
valley glaciers came onto a lowland plain, they spread out and
joined into a single ice mass called a piedmont glacier. When the
ice melted about 12,000 years ago, temporary lakes were formed in
which deposits of fine silt and clay accumulated. Laminated clays
of this sort have been used for brick or tile making, in the area
which is now the nearby Tilesheds Nature Reserve.
Further information can be found at an information board at the
above coordinates. In order to log this cache please take a photo
of it or the island with your gps and email me the aproximate
thickness of the ice sheets that traveled to make this feature.
