Craven Fault System
The Craven Fault System is the name applied by geologists to the group of crustal faults in the Pennines that form the southern edge of the Askrigg Block and which partly bounds the Craven Basin. Sections of the system's component faults which include the North, Middle and South Craven faults and the Feizor Fault are evident at the surface in the form of degraded faults scarps where Carboniferous Limestone abuts millstone grit. The fault system is approximately coincident with the southwestern edge of the Yorkshire Dales National Park and the northeastern edge of the Bowland Fells.
The Craven Faults are major crustal fractures across the Pennines. These faults constitute a zone crossing the backbone of England from west to east commencing near Leck, Lancashire at 54°11′26″N 2°31′38″W / 54.190507°N 2.527339°W then branching three ways:
The Craven Gap is sometimes called the Aire Gap, but to do so necessitates including the Aire Fault; that runs from the south end of the South Craven Fault: from Gargrave towards Leeds. Although of less amplitude than the three Craven faults the course of the Aire Fault is made more apparent by the River Aire. The broad Aire Gap separates the Yorkshire Dales from the Bowland Fells and the Millstone Grit plateaux of the South Pennines.
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