Editing Craven Fault Zone — Malham to Settle - an excursion

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=== Locality 16, Sugar Loaf Hill [SD 836 638] ===
 
=== Locality 16, Sugar Loaf Hill [SD 836 638] ===
  
Cross the wall and continue east for 100 m to steps providing access to the footpath leading to Sugar Loaf Hill, in the High Hill fault block. Proceed 350 m southwards to the base of the conical shaped Sugar Loaf Hill. The dark grey limestones dipping at 18° immediately to the west are Lower Hawes Limestone. The base of this limestone provides a reliable datum on which the throw of the MCF can be calculated (here 170 m). Please note that this area of Hawes Limestone has been inadvertently shaded as Cove Limestone on the solid edition of the Settle 1:50 000 geological map, but corrected on the drift edition. The strata forming Sugar Loaf Hill are early Namurian (Pendleian) in age and '''unconformably''' overlie the limestones of the lower part of the Wensleydale Group. Most of the hill is composed of intercalated mudstone, siltstone and thin cherty limestone (30 m in all), collectively named the Sugar Loaf Shales, while the top of the hill is capped by 5 m of shelly (brachiopod) wackestone, the lower third of the Sugar Loaf Limestone. The local names reflect the unique character of these units, which are correlatives of the nearby Upper Bowland Shales, but more analogous in lithology to the Namurian part of the Wensleydale Group (the Main Limestone and underlying siltstones as found, for example, on Fountains Fell). The Sugar Loaf succession represents the localized deposition of a late Wensleydale Group facies on an isolated fault block, when the adjacent tract was typically characterized by the deeper water deposits of Bowland Shales. These stratigraphic relations indicate the relative independence and variable subsidence rates of the isolated blocks forming the hanging wall of the MCF.
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Cross the wall and continue east for loo m to steps providing access to the footpath leading to Sugar Loaf Hill, in the High Hill fault block. Proceed 350 m southwards to the base of the conical shaped Sugar Loaf Hill. The dark grey limestones dipping at 18° immediately to the west are Lower Hawes Limestone. The base of this limestone provides a reliable datum on which the throw of the MCF can be calculated (here 170 m). Please note that this area of Hawes Limestone has been inadvertently shaded as Cove Limestone on the solid edition of the Settle 1:50 000 geological map, but corrected on the drift edition. The strata forming Sugar Loaf Hill are early Namurian (Pendleian) in age and '''unconformably''' overlie the limestones of the lower part of the Wensleydale Group. Most of the hill is composed of intercalated mudstone, siltstone and thin cherty limestone (30 m in all), collectively named the Sugar Loaf Shales, while the top of the hill is capped by 5 m of shelly (brachiopod) wackestone, the lower third of the Sugar Loaf Limestone. The local names reflect the unique character of these units, which are correlatives of the nearby Upper Bowland Shales, but more analogous in lithology to the Namurian part of the Wensleydale Group (the Main Limestone and underlying siltstones as found, for example, on Fountains Fell). The Sugar Loaf succession represents the localized deposition of a late Wensleydale Group facies on an isolated fault block, when the adjacent tract was typically characterized by the deeper water deposits of Bowland Shales. These stratigraphic relations indicate the relative independence and variable subsidence rates of the isolated blocks forming the hanging wall of the MCF.
  
 
=== Locality 17, High Hill, eastern side [SD 837 634] ===
 
=== Locality 17, High Hill, eastern side [SD 837 634] ===
  
Continue southwards for a further 300 m to where the footpath runs close to the wall, following the line of a northwest-trending subsidiary fault, to the west of which are large replacive '''dolostone''' bodies in the Gordale Limestone. Observe the Gordale Limestone immediately to the west where well-bedded limestones are dipping at about 15°. Proceed southwards to the remains of a limekiln just west of the path. The quarried limestone section adjacent to the kiln exposes unbedded bank facies of the marginal 'reef' limestones. Notice that the bedded Gordale Limestone (previously viewed) overlaps these 'reef' limestones. The Gordale Limestone in this vicinity thus formed at the very edge of the original shelf, and would have passed into or lapped onto the marginal build-ups somewhere out of the exposure to the south; the present juxtaposition of beds reflecting erosion on the front of the shelf margin build-up.
+
Continue southwards for a further 300 m to where the footpath runs close to the wall, following the line of a northwest-trending subsidiary fault, to the west of which are large replacive dolostone bodies in the Gordale Limestone. Observe the Gordale Limestone immediately to the west where well-bedded limestones are dipping at about 15°. Proceed southwards to the remains of a limekiln just west of the path. The quarried limestone section adjacent to the kiln exposes unbedded bank facies of the marginal 'reef' limestones. Notice that the bedded Gordale Limestone (previously viewed) overlaps these 'reef' limestones. The Gordale Limestone in this vicinity thus formed at the very edge of the original shelf, and would have passed into or lapped onto the marginal build-ups somewhere out of the exposure to the south; the present juxtaposition of beds reflecting erosion on the front of the shelf margin build-up.
  
 
=== Locality 18, Corner of High Hill Lane and Stockdale Lane [SD 836 630] ===
 
=== Locality 18, Corner of High Hill Lane and Stockdale Lane [SD 836 630] ===

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