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Figure 7. (a) Fissure 1 showing convoluted dark-grey palynomorph-bearing (FP1.1) sandy mudstone of typical Westbury-type lithology ‘WL’ with fractured calcite band. The Carboniferous Limestone block ‘CLB’ has slipped and caused the disruption of the bed. (b) Fissure 1; the lower quarry scree has been removed (Fig. 7a is outlined) and a more complete exposure below the slipped Carboniferous Limestone block of (a) is shown. There is dark-grey convoluted sandy mudstone to the left of the fractured calcite band (‘fc’ in Fig. 7c) and a near-horizontal layered alternation of mudstone and conglomerate sequence on the right. The slumped sequence will have been related to earth movements and was formed after deposition, which is clearly demonstrated by the broken calcite and mineral vein. Such seismic movements have been identified by Mayall (1983) at the beginning of the Cotham Member, and Simms (2006) regards the cause as bolide impact. The palynomorph assemblage FP1.2 (Table 2) was taken from the right-hand side and the sample point is shown in close-up in Figure 7c. The scale-figure (DIW) is 1.7 m tall. (c) Fissure 1. A close-up of the sequence described in (b); there are repeating conglomeratic bands that fine upwards (graded bedding) and have fine laminated mudstones between them. Note location of FP1.2 and ‘fc’ the fractured calcite vein. (d) Fissure 1. A close-up of (c) that shows two conglomeratic bands (a clast is circled). (e) Thecodontosaurus. BRSUG specimen 23613. Lateral view of left ilium showing characteristic short anterior process ‘AP’. The bone is whitish coloured which is typical of many of the Thecodontosaurus bones of the original discovery at Tytherington. Fissure 2, x0.75, scale bar 2 cm. (f) Thecodontosaurus. BRSUG specimen 23613. Medial view of same left ilium as (e) with dark-grey silty sandstone ‘GSS’ matrix attached. This matrix is lithologically the same as the rock abutting the Thecodontosaurus bones that produced palynomorph assemblage FP2.1. Fissure 2, x0.75, scale bar 2 cm. (g) Thecodontosaurus. BRSUG specimen 23642. A postero-medial view of part of a white and yellow coloured right femur showing well-developed trochanter ‘tr’ with muscle scar ‘ms’. Fissure 2, x0.75, scale bar 2 cm. (h) Acid-etched rock showing brown- and white-coloured bones of Thecodontosaurus ‘Th’ in a breccia above finely laminated cross-bedded calcareous silty sandstone, including a layer of the grey lithology that elsewhere, and below the Thecodontosaurus breccia, yielded the palynomorph assemblage FP2.1. Fissure 2, x0.6, scale bar 2 cm. (i) Opposite side of (h) showing angular white dolomitized Carboniferous limestone ‘DCL’ breccia with clasts above, and cutting into, finely laminated grey silty sandstone. Fissure 2, x0.6, scale bar 2 cm.

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