The Inferior Oolite and Contiguous Deposits of the Crewkerne District (Somerset)

Abstract

I. Introduction. In this paper I propose to give a detailed description of the Inferior Oolite and contiguous deposits of the Crewkerne district. The extent of this district, for the purpose of the present communication, will be observed from the map (fig. 1, p. 146). (i) Geographical extent of the Inferior Oolite.—Reference to the Geological Survey Map, Sheet XVIII (Old Series) will show (1) that the most extensive tract where the Inferior-Oolite limestones occur, free from overlying rocks, is in the immediate neighbourhood of Crewkerne; (2) that there are numerous masses well separated from the principal tract; and (3) that the beds are affected by numerous faults. (ii) Previous literature.—Comparatively little information has been published concerning the Inferior Oolite and immediate sub- and superjacent deposits of this district, with the exception of Ham Hill. This locality, famous for its warm-coloured building-stone, attracted considerable attention on the part of Charles Moore, 1 James Buckman, 2 and H. B. Woodward. 3 The second author was correct in his local correlations of the Ham-Hill Stone—a conclusion also arrived at by H. B. Woodward —but was incorrect in his correlation with the Cotteswolds; although his recognition of the Cephalopoda-Bed below the Sands at Midford (near Bath) and around Yeovil, but above the Sands of the Cotteswolds, came nearer to the truth than was imagined. The actual solution arrived at by Mr. S. S. Buckman—published with a descriptive section in 1889 4 —that the Ham-Hill Building-Stone and its subjacent sands were a thick development of only a small middle portion