Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/172

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138 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 24,


Section in Pit No. 4 (continued).

Lithology. Observations.

10. Narrow stone, 2 in. Fossils as in 12.

11. Clay with sometimes a band of white stone, 2 ft. 3 in.

12. Sandy stone weathering white, 4 Modiola minima. or 5 in. Myacites musculoides (var. β̞).

13. Blue clay with a spring of water at the top, which colours the section red, 6 ft.

14. Stone, 4 in. Fossils as in 12.

15. Clay like. 13, 10 ft. to base of the section.

It is not difficult to correlate these beds with those of pit No. 3. The bed No. 4 is obviously equivalent to the irregular stone layer in No. 30 of pit No. 3, No. 2 to the oyster-bed No. 25, No. 8 to No. 33, and No. 12 to 38 ; so that we get two lower beds here. Even yet, however, we reach no bone-bed nor any signs of the Keuper marls. The beds of stone in this quarry are very finely laminated and weather white, altogether recalling the White-Lias bands of the south of England. As, however, several beds of clay (the " contorta" shales) and stone there intervene above the bone-bed, it is probable that the true horizon of the latter is not reached here, Avicula contorta not having been met with even in the lowest clays. Mr. Norwood, in his paper, states that here the Lias is seen gradually changing into the Keuper ; but it certainly does not in this quarry, which contains the lowest beds discovered. Can he have mistaken the red weathering of the two lower clay-beds for the red Keuper marls ?

No fossils have been found in this quarry beyond those mentioned in the section ; and Foraminifera are entirely wanting.

The only place in this neighbourhood where there is any likelihood of seeing lower beds leading down into the Keuper, must be somewhere between Market Weighton and Pocklington, some six or seven miles from Cliff.

About 3 furlongs further on we come to another pit, No. 5, which is not now worked, and consequently the section is not well exposed. In this the white limestone is seen at the base, and oyster-bands occur about 10 feet above it ; it has probably therefore been excavated in the same beds as pit No. 4.

The last pit in the series, or pit No. 6, is situated less than a quarter of a mile from No. 5, just at the cross road leading to Hotham. We have there the following section.

Section in Pit No. 6.

Lithology. Observations.

Surface-soil Good thickness.

1. Soft calcareous sands, 8 in.

2. Sandy clay, 7 in. | 2, 3, 4 contain broken fragments of Ostrea irregularis.

3. Stone, 7 in.

4. Clay like 2, 8 in. | 2, 3, 4 irregular.