Editing Craven Fault Zone — Malham to Settle - an excursion

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=== Locality 8, Calamine Mine 'New Shaft' [SD 876 640] ===
 
=== Locality 8, Calamine Mine 'New Shaft' [SD 876 640] ===
  
A concrete cap with a metal door covers a 21 m deep shaft, dug in 1806 for access to the mine, which yielded '''smithsonite''' (calamine) from a Quaternary cavern system some 70 m in length. The mineral occurs as a sediment flooring the caverns, and was discovered during copper mining in 1788. The calamine was originally brought to surface via the difficult access of the copper mine to the west (see Locality 9). The New Shaft (rediscovered in 1944) was constructed to ease the handling of the mineral. It is estimated that up to 5000 tons of calamine, used largely in brass-making, were extracted before the mine was closed in 1830.
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A concrete cap with a metal door covers a 21 m deep shaft, dug in 1806 for access to the mine, which yielded smithsonite (calamine) from a Quaternary cavern system some 70 m in length. The mineral occurs as a sediment flooring the caverns, and was discovered during copper mining in 1788. The calamine was originally brought to surface via the difficult access of the copper mine to the west (see Locality 9). The New Shaft (rediscovered in 1944) was constructed to ease the handling of the mineral. It is estimated that up to 5000 tons of calamine, used largely in brass-making, were extracted before the mine was closed in 1830.
  
 
=== Locality 9, Pikedaw Head Gate [SD 875 640] ===
 
=== Locality 9, Pikedaw Head Gate [SD 875 640] ===
  
Proceed westward from the New Shaft through the gate in the wall. The disturbed ground immediately west of the wall is the result of copper workings and consists of shafts, bell-pits and their spoil. The copper deposits were in poorly differentiated veins and impregnations and were very difficult to work. The heap of limestone debris to the west of the gate is that from the 'principal copper shaft', and it was by this exit that calamine was initially brought to surface. Continuing westwards, observe the ground to the south (eg 200 m west of Locality 9). Here a line of shake holes defines the contact of the Upper Bowland Shales on the Hawes Limestone. The Namurian shales '''overlap''' an eroded limestone surface north of the MCF, a manifestation of a substantial '''throw''' in the MCF and subsequent erosion of the footwall scarp before the deposition of the shales. This buried fault-scarp is an example of the pre-Namurian topography.
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Proceed westward from the New Shaft through the gate in the wall. The disturbed ground immediately west of the wall is the result of copper workings and consists of shafts, bell-pits and their spoil. The copper deposits were in poorly differentiated veins and impregnations and were very difficult to work. The heap of limestone debris to the west of the gate is that from the 'principal copper shaft', and it was by this exit that calamine was initially brought to surface. Continuing westwards, observe the ground to the south (eg 200 m west of Locality 9). Here a line of shake holes defines the contact of the Upper Bowland Shales on the Hawes Limestone. The Namurian shales overlap an eroded limestone surface north of the MCF, a manifestation of a substantial throw in the MCF and subsequent erosion of the footwall scarp before the deposition of the shales. This buried fault-scarp is an example of the pre-Namurian topography.
  
 
=== Locality 10, Kirkby Fell viewpoint [SD 870 638] ===
 
=== Locality 10, Kirkby Fell viewpoint [SD 870 638] ===
  
The MCF crops out about 100 m south of the path, the rising ground of Kirkby Fell beyond being Pendle Grit Formation capped by Grassington Grit. To the southwest, two leaves of Grassington Grit form the prominent Rye Loaf Hill. To the west the path descends and crosses a narrow northnorthwest-trending dry valley, developed along another of the subsidiary extensional faults which cross the ground between the MCF and NCF. This subsidiary fault is linked with several others to the north, forming a complex zone of westward down-stepped slices. Silicified limestone analogous to that seen at Locality 7 is exposed adjacent to the path, and a line of small mineral workings follows the fault. Spoils have yielded '''sphalerite''', galena, '''malachite''', azurite and '''baryte'''.
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The MCF crops out about loom south of the path, the rising ground of Kirkby Fell beyond being Pendle Grit Formation capped by Grassington Grit. To the southwest, two leaves of Grassington Grit form the prominent Rye Loaf Hill. To the west the path descends and crosses a narrow northnorthwest-trending dry valley, developed along another of the subsidiary extensional faults which cross the ground between the MCF and NCF. This subsidiary fault is linked with several others to the north, forming a complex zone of westward down-stepped slices. Silicified limestone analogous to that seen at Locality 7 is exposed adjacent to the path, and a line of small mineral workings follows the fault. Spoils have yielded sphalerite, galena, malachite, azurite and baryte.
  
 
=== Locality 11, Great Scar viewpoint [SD 866 639] ===
 
=== Locality 11, Great Scar viewpoint [SD 866 639] ===

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