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Shetland Landscapes
Shetland displays some of the most complex and varied geology to be found anywhere in Britain. The islands consist partly of metamorphic rocks - ancient rocks, mainly of sedimentary origin which were changed by the heat and pressure associated with the intrusion of igneous rocks during the Caledonian mountain building period - and partly of sedimentary and volcanic rocks of the Old Red Sandstone which were laid down and folded towards the end of that orogeny. Shetland links the Norwegian, Scottish and East Greenland parts of the former Caledonian terrane that long predates the opening of the North Atlantic. It also carries some of Scotland's oldest rocks, a sliver of deep ocean crust and a host of unusual minerals.
The landscape of Shetland has been sculpted from this diverse geology by rivers, glaciers and the sea over the last few million years. Major landforms survive from before the Ice Age, notably the great granite whaleback of Ronas Hill. Hundreds of lochans plus the firths that separate and penetrate the islands attest to deep glacial erosion yet in a few places peat deposits survive from the last interglacial warm period. The coastline is stunning in its variety and grandeur with an outer coast showing some of the most spectacular cliff scenery in the world and inner coast adorned by sandy beaches and ayres. The richness of the geology and geomorphology is the foundation for the many layers of natural habitat and human history that make Shetland so special.
Scotland's landscapes
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