Geological structures exposed - for iPad/Mac/PC
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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.
Overview of the Orogenic Belt
The three main components of the Orogenic Belt; Lewisian gneisses, Torridonian sandstone and sediments laid down from Cambrian times.
Ductility of the Structures
The ductility of structures of rocks from the Dalradian supergroup.
Kinematic indicators
Evidence of indicators which suggest the direction of movement within slices of rock.
Using dikes as kinematic indicators
A dike that is deflected 45 degrees when entering a sheer zone provides a valuable kinematic indicator.
Shear Zone movement
An assymetric porphyroblast reveals a sense of movement within Myelenite gneissic banding.
Locating synforms
Asymmetric fold pairs and ductile structures in the inner zone at Scotlands Kilmore Bay.