The Earth Shaping Power of Glaciers

This large limestone boulder tells a number of stories about the last glaciation of the Furness peninsula when it was covered by ice which had travelled south from the valleys around Coniston in the Lake District.  Because the solid geology on the peninsula includes a boundary between the limestone at this location, and different older geology a little further to the north, it is possible, together with the known direction of travel of the ice, to place where this boulder originated.  It was approximately 320 metres to the north behind the boulder as seen here.  A fractured surface on one side identifies where it was snapped off the parent bedrock by the force of the passing glacier.  The curved and smoothed - once smoother but now weathered - surfaces speak to the abrading action of the ice and carried debris, as it passed by the still anchored boulder.  Eventually the glacier’s relentless force, together with freeze/thaw ice forces within initial fracture cracks, led to the dislodgement of the boulder.   It is quite likely that earlier Ice Ages had also played their part in the sculpting of those curved smooth surfaces.  Notwithstanding its large size, once dislodged, it was then transported by the ice to its present position where dissolution and further freeze/thaw forces have continued to fracture and modify the appearance of this distinctive boulder now crowned by a well-established growth of ivy.  The image of permanence, however, is in reality nothing more than a beguiling pause awaiting the next Ice Age when a further stage of its travels will occur.