Excursion to Leith Hill. Saturday, June 1st, 1912 - Geologists' Association excursion
Excursion to Leith Hill. Saturday, June 1st, 1912. (Transcription from Circular, 145, Session 1911–1912)
DIRECTOR : DOUGLAS LEIGHTON, F.G.S.
EXCURSION SECRETARY : MISS CADMORE, 4, Ulundi Road, Blackheath.
Leave, London Bridge, L.B. & S.C. Railway, by 12.38 train, due at Holmwood 2.9 Take cheap day return tickets to Holmwood, 3s. each.
From Holmwood proceed via Moorhurst Road to a small pit south-east of Anstiebury Farm, showing Chert and Lower Sand in a much disturbed condition. Probably this disturbance is due to slipping. Thence cross the fields to Coldharbour. Here the valley excavated by the Pipp Brook, and exposing the Atherfield and Weald Clay, can be seen. There are some interesting features in connection with the formation of this valley which can be discussed here.
In Coldharbour village a pit will be seen in the Lower Sands which overlie the Atherfield Clay everywhere in Surrey. On the way up to Leith Hill many sections in Chert Beds can be inspected. At Cockshott Hollow, just before the summit of the hill is reached, the long narrow valley formed by the head-waters of the Tilling Bourne can be seen. For some way down the valley the Atherfield Clay is exposed till it is cut off by an increase in the dip of the beds. Several interesting points dealing. with the physical structure of this part will be brought forward here.
From the top of Leith Hill, 965 ft. 0.D., a magnificent view can be obtained all over the Weald and extending to the South Downs. Proceed in a north-westerly direction to Abinger Bottom. This is situated at the head of another small valley which cuts down to the Atherfield Clay. On the Geological Survey map a small fault is marked on the west side of the valley. It will be shown that if there is a fault at all it probably extends right through the outcrop from north to south, but more probably there is no fault, but a rather sharp flexure ; the direction of this is marked on the map by the broken line A.A.
Walk down the valley to the picturesque village of Friday Street, and thence westward to Hollow Lane, where there is a good section showing Bargate Stone resting on Chert Beds. At the northern end of the lane the beds have a slightly southerly dip, the general dip of the beds in this district being north.
Proceed to the Wotton Hatch, where tea will be taken. Plain tea 1s. (eggs 2d. each). After tea walk down Coast Hill, where there is a long lane section in Chert Beds. The long Rookery fault, with a throw here of about 60 ft., cuts across the lower end of the road, and the Bargate Stone is exposed on the northern side. At Westcott Heath there is a large pit in Upper or Folkestone Sands. This part north of the fault is mapped in the Geological Survey map as being of Hythe age, but it has been demonstrated clearly that this is an error and that it is of Folkestone age.
It has frequently been pointed out that it is very difficult to work satisfactorily in this part of Surrey if the official sub-divisions of the Lower Greensand are used, but for convenience it may be mentioned that, roughly, the Upper Sand represents the Folkestone Beds, the Bargate Stone may represent the Sandgate Beds, but may be higher or lower, while the Chert Beds and Lower Sand are equivalent to the Hythe Beds.
Drive from Westcott Heath to Dorking Station (L.B. & S.C.R). Price 1s. 6d., if more than 12, is 1s. each. Return train from Dorking 8.23, due at London Bridge 9.42.
Geological Survey Map (Old Series), Sheet 8. Ordnance Map, 6 inch, Sheet 33, S.E., S.W. and N.W.
1875. TOPLEY, W.—"Geology of the Weald." Mem. Geol. Survey.
1893. LEIGHTON, T., and BOULGER, J. S. ."On the Lower Greensand Area between Wotton and Dorking." Proc. Geol. Assoc., vol. xiii, p. 4.
1893. LEIGHTON, T., and BOULGER, J. S. "Excursion to Abinger." Proc. Geol. Assoc., vol. xiii, p. 163,
1895. LEIGHTON, T., and BOULGER, J. S. "The Lower Greensand above the Atherfield Clay of East Surrey." Quart. journ. Geol. Soc., vol. li, p. 101.
1896. LEIGHTON, T., and BOULGER, J. S. "Excursion to Dorking and Leith Hill." Proc. Geol. Assoc. vol. xiv, p. 331.