Tertiary Outliers on the North Downs

Abstract

IN August of last year (NATURE, vol. xxxiv. p. 341), I ventured to draw a distinction between the unfossiliferous sands found at certain places on the North Downs and the fossiliferous deposits at Lenham. For reasons assigned, I suggested a certain degree of probability of their being of Bagshot age, and indicating a former extension by overlap of the higher beds of that important Eocene formation. This summer I have had opportunities of examining all the principal outliers referred to; and I must say that I am strongly impressed with the Bagshot character of these unfossiliferous sands, and of the well-rolled flint pebbles associated with them, in some cases (as at Headley) in great quantity. I speak only of those which can be identified with some degree of certainty as Tertiary beds in situ. The sands at Netley Heath and at Chipstead have a remarkable Upper Bagshot facies. Those at Headley do not present such a strong character in this respect, but I have no hesitation in referring them on lithological grounds to the Bagshot series.