Editing Permian and Carboniferous rocks of Knaresborough - an excursion

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=== Locality 4 [SE 355 559] ===
 
=== Locality 4 [SE 355 559] ===
  
Proceed southwards along the road to the south end of the garden of the last house (Amtree House) on the east of the road. Please keep out of the private garden. At the far entrance to the grounds, looking up at the rock face to the east, the unconformity between the massive sand-wave facies of the Cadeby Formation and the underlying Upper Plompton Grit is exposed, now sadly overgrown and best seen in winter. The sandstone is reddened and takes the form of a rounded buried hill with an exposed relief of 8 m and a width of 32 m ([[:File:YGS_YORKROCK_FIG_13_02.jpg|Figure 13.2]]). The overlying Cadeby Formation covers the buried hill with subconcentric drapes of beds 0.1–0.15 m thick. On its flanks they pass laterally into large-scale (1—10 m) cross-bedding. The Cadeby Formation here comprises fine-grained crystalline to granular dolomite with sporadic poorly preserved ooliths.
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Proceed southwards along the road to the south end of the garden of the last house (Amtree House) on the east of the road. Please keep out of the private garden. At the far entrance to the grounds, looking up at the rock face to the east, the unconformity between the massive sand-wave facies of the Cadeby Formation and the underlying Upper Plompton Grit is exposed, now sadly overgrown and best seen in winter. The sandstone is reddened and takes the form of a rounded buried hill with an exposed relief of 8 m and a width of 32 m ([[:File:YGS_YORKROCK_FIG_13_02.jpg|Figure 13.2]]). The overlying Cadeby Formation covers the buried hill with subconcentric drapes of beds 0.1–0.15 m thick. On its flanks they pass laterally into large-scale (t–m) cross-bedding. The Cadeby Formation here comprises fine-grained crystalline to granular dolomite with sporadic poorly preserved ooliths.
  
 
=== Locality 5 [SE 357 557] ===
 
=== Locality 5 [SE 357 557] ===
  
Continue southwards to the car turning point. Northeast of here the unconformity at the base of the Cadeby Formation dips down into a concealed valley, but reappears in the quarry east of the road. Here 3.6 m of Carboniferous sandstone (Upper Plompton Grit) is present beneath 13.5 m of Cadeby Formation. The reddened and weathered sandstone is very coarse to granule-grained, '''feldspathic''', with '''quartz''' pebbles, and occurs in very thick cross-bedded units. At the base of the overlying limestone there is a thin impersistent bed (0–0.1 m) of yellow, very coarse-grained sandstone with a dolomitic cement. It is not apparent whether this is part of the Carboniferous sequence, re-cemented with dolomite, or a very sandy bed at the base of the Permian. The overlying thin, medium and thick beds comprise dolomite with quartz grains in the lowest 0.5 m or so.
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Continue southwards to the car turning point. Northeast of here the unconformity at the base of the Cadeby Formation dips down into a concealed valley, but reappears in the quarry east of the road. Here 3.6 m of Carboniferous sandstone (Upper Plompton Grit) is present beneath 13.5 m of Cadeby Formation. The reddened and weathered sandstone is very coarse to granule-grained, feldspathic, with quartz pebbles, and occurs in very thick cross-bedded units. At the base of the overlying limestone there is a thin impersistent bed (0–0.1 m) of yellow, very coarse-grained sandstone with a dolomitic cement. It is not apparent whether this is part of the Carboniferous sequence, re-cemented with dolomite, or a very sandy bed at the base of the Permian. The overlying thin, medium and thick beds comprise dolomite with quartz grains in the lowest 0.5 m or so.
  
 
=== Locality 6 [SE 357 557] ===
 
=== Locality 6 [SE 357 557] ===
  
About 100 m southeast of Locality 5 the same unconformity rises to the top of the old quarry in the private grounds east of the road, from where it can be well seen. The quarry should not be entered. The section now exposes 10.5 m of Carboniferous sandstone overlain by 4 m of dolomite. This shows that locally the relief on the unconformity is at least 8 m.
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About loo m southeast of Locality 5 the same unconformity rises to the top of the old quarry in the private grounds east of the road, from where it can be well seen. The quarry should not be entered. The section now exposes 10.5 m of Carboniferous sandstone overlain by 4 m of dolomite. This shows that locally the relief on the unconformity is at least 8 m.
  
 
=== Locality 7 [SE 361 570] ===
 
=== Locality 7 [SE 361 570] ===

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