The Stratigraphical Relations of the Red Rock at Hunstanton

IN his interesting paper entitled “ The Petrography of the Hunstanton Red Rock”1 Dr. R. H. Rastall arrived at conclusions regarding the relation of the Red Rock to the strata below and above it which are strikingly at variance with the result of our own examination of the series exposed in the well-known cliffsection at Hunstanton.2 While we considered that the Red Rock has no connection with the underlying Carstone, though resting on it with apparent conformity, and that the junction between these contrasted, beds marks a stratigraphical gap of great magnitude, we found no reason to recognize a break between the top of the Red Rock and the overlying Chalk. Dr. Rastall, on the other hand, impressed by the fact that there is a certain gradation and an appearance of conformability between the Carstone and the Red Rock, took this as showing continuity between these deposits; while the appearance of a physical break at the top of the Red Rock seemed to him to contradict our view that the top bed of the Red Rock and the Chalk above (“ Sponge Bed ”) are inseparable geologically.