Understanding mountain building involves unraveling how and why rocks deform. Geologists Nigel Harris and John Whalley tour the Scottish segment of the Caledonian orogenic Belt to untangle the kinematics and the chronology of deformation. This material forms part of The Open University course S339, Understanding the continents.
The three main components of the Orogenic Belt; Lewisian gneisses, Torridonian sandstone and sediments laid down from Cambrian times.
Transcript -- The three main components of the Orogenic Belt; Lewisian gneisses, Torridonian sandstone and sediments laid down from Cambrian times.
Transcript -- Evidence of indicators which suggest the direction of movement within slices of rock.
A dike that is deflected 45 degrees when entering a sheer zone provides a valuable kinematic indicator.
Transcript -- A dike that is deflected 45 degrees when entering a sheer zone provides a valuable kinematic indicator.
An assymetric porphyroblast reveals a sense of movement within Myelenite gneissic banding.
Transcript -- An assymetric porphyroblast reveals a sense of movement within Myelenite gneissic banding.
Asymmetric fold pairs and ductile structures in the inner zone at Scotlands Kilmore Bay.
Transcript -- Asymmetric fold pairs and ductile structures in the inner zone at Scotlands Kilmore Bay.
Geologist John Whalley explains how in structural chronology downwards facing folds will cause the rock structure to start younging.
Transcript -- Geologist John Whalley explains how in structural chronology downwards facing folds will cause the rock structure to start younging.
The evidence for an Arc-continent collision around 460 million years ago in the Scottish Highlands.
Transcript -- The evidence for an Arc-continent collision around 460 million years ago in the Scottish Highlands.