Sutton Bank 451483
Regional and topographical overview of geological setting. Roulston Scar (Upper Jurassic Lower Calcareous Grit on left of photo; Hood Hill towards centre , separated from Roulston Scar by a Quaternary glacial melt water channel. Flat lying Vale of York in the distance covered by Quaternary deposits overlying Permo-Triassic sediments. Features of interest from this vantage point are the Middle and Upper Jurassic rocks forming the escarpment and outliers, and the absence of the Oxford Clay around Roulston Scar which has influenced the style of landslides, including the lack of cambering in this area.

Shaw's Gate Quarry (SE 5240 8220)
Shaw's Gate Quarry  Spectacular contemporaneous deformation structures, scouring and sedimentological features in the lower part of the Hambleton Oolite (Upper Jurassic; Corallian Group). Evidence for debris flows, de-watering, scouring, convolute bedding, soft-sediment deformation and injection dykes, were attributed to highly mobile ooidal shoals deposited in shallow water towards the shelf edge, possibly influenced by contemporaneous seismic activity resulting from local tectonics.

Raven's Gill SE452481
A unique unconformity: Oldstead oolite directly overlying Kellaways Rock.
Due to uplift during or after deposition of the Kellaways Rock, Oxford Clay was either completely eroded away or not deposited. The time gap represented by the unconformity is equivalent to about six ammonite zones of the full coastal succession.

Mowthorpe Quarry SE468468

Originally mapped by Fox-Strangways as an atypical lithofacies of the Dogger Formation, the limestone includes the bryozoan Haploecia straminea (now Collapora straminea) normally associated with, and typical of, the much later transgressive marine unit, the Lebberston (Millepore/Whitwell Oolite) Member, (Middle Jurassic, Cloughton Formation). Discussion took place as to whether the exposure is a local, and atypical carbonate lithofacies of the heterogeneous Dogger Formation (Aalenian), or does it represent local downcutting of the Lebberston Member (early Bajocian) influenced by tectonics associated with the Market Weighton High. On balance, the weight of opinion favoured the former, since the Dogger is also known to exhibit local carbonate lithofacies near Sutton Bank (Powell et al, 1992).

Hand specimen and microscope photo of a cross section  of Collapora straminea as seen at Mowthorpe Quarry

Burythorpe Quarry SE478465
The quarry is being worked for silica (moulding) sand and exposes an excellent section in the Osgodby Formation (Callovian). Here, the unit is very different from the lithology seen earlier in Raven's Gill, and comprises soft, very well sorted, fine-grained, white-grey sand with very large (up to 'car-size') carbonate-cemented nodules (concretions). Some of the latter contain ammonites (Cardioceras sp.) as seen in the photo to the left.

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