Figure 4. Simplified large-scale geological map and geological succession of the area around Tytherington Quarry. The limestone was quarried from the Black Rock Group. Also note the outcrop of bedded Penarth Group at a height of 96 m, about 600 m south of the quarry. From BGS map sheet ST 68 NE, co-ordinates used are British National Grid. Geological column from Kellaway & Welch (1993).