Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/187

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TYLOR—QUATERNARY GRAVELS.
93


for examining the dip of the gravel, and showing the relation of the thick brick-earth beds deposited at angles as high as 19°, 17°, 14°, 11°, and 9°, in curves falling to the river. The beak of chalk is shown at about 18 feet above the Ordnance datum-line. It is about 10 feet long; and the junction with the escarpment of chalk is not seen.

This drawing is by Mr. S. Skertchly, to natural scale. Fig. 27 is from a drawing I made in 1866, near the Line I J.


Fig. 27.—Section in Crayford Pit.


The mass of Thanet sand B, below the beak of chalk near A, was then well seen; patches of these sands also occur in the brick-earths and gravels C. The dip was 15° where marked, and that of the covering bed only 2°. Fig. 27 is to natural scale, and represents a greater length of section than fig. 26. This part of the pit has recently

Fig. 28.—Section of part of the Cyrena-bed, Crayford.

been excavated; so I give both sections for reference. The coarse gravel in front of the beak is pushed out horizontally into the finer beds of sand, and divides into fine points. There were other beaks of chalk visible at G and H.