Excursion to Dartford Heath. Saturday, May 17th, 1913 - Geologists' Association excursion

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Geologists' Association Circular No. 155. Session 1912-1913. p.9-11.[edit]

Excursion to Dartford Heath. May 17th, 1913. (Transcription from: GA Circular No. 155. Session 1912-1913. p.9-11)[edit]

DIRECTOR: A. L. LEACH, F.G.S.

EXCURSION SECRETARY: MISS EDITH CADMORE, 4,Ulundi Road, Blackheath, S.E.

Meet Excursion Secretary under clock at 1.30. Special return fare 1s. 10d. Leave Cannon Street at 1.46 p.m. Meet the Director at 2.29 p.m. at Crayford Station.

Since the Excursion to Dartford Heath in March, r9111 new excavations made inWansunt gravel-pit and on the slightly lower ground immediately to the north, haveshown that the section given in illustration of the paper on tile Dartford Heath Gravel(see References) needs modification. The implementiferous channel (W) is narrowerthan had been anticipated, and at a lower levet there ave indications of a later channelwhich has been largely filled up by earthy rubble.

TWO cuttings, each about 90 yards long, intersect this unstratified material, inwhich calcined flints and roughly chipped implements occur upwards of lo ft. belowthe ground surface. The upper trench (B) shows the ferruginous clayey base C‘ ironpan ") of the Dartford Heath Gravel resting on iron-stained Thar, et Sand. Somebones and fragments of teeth have been obtained from the base of the gravel.

From Crayford Station the party will walk to the northern edge of the Heath toebserve the gereral aspect o the district, The new cuttings will then be examined and some time spent in Wansunt pit, where the implementiferous channel (W) may still be traced.

A new pit near Bowman's Lodge may, by the date of the Excursion, show a complete section of the Dartford Heath Gravel.

Tea at Bowman's Lodge (1s. 0d.) . After tea it is proposed to walk through the fields into Bexley, noting on the way some additional features of interest on Dartford Heath and in the dry valley (in Thanes Sand) of a former tributary of the Cray.

Total walking distance 4 miles.

Trains leave Bexley 6.59 p.m, and 7.32 p,m., arriving at. Cannon Street. at 7.37 or 8.12.

Figure 2.—Sectron from Crayford Siation to Dartford Heath, showing the positions of two channels filled with deposits of later age than the Dartford Heath Gravel.

b. Red Gravel, Dartford Heath Gravel

a. False-bedded Gravel Gravel, Dartford Heath Gravel

A. Lower Trench.

B. Upper Trench.

W. Channel with Acheulean implements.

X. Later Channel.

Length of Section about 700 yards. Vertical Scale out three times the horizontal.

Figure 3. —Section along the south-western side of the Upper Trench B.

a. Dartford Heath Gravel.

c. Pale Friable Loam (? decalcified marl).

d. Unstratified Earthy Gravel.

REFERENCES.

Ordnance Survey Map, 6 inch (1910 edition), Kent. Sheet ix, N.W.

Geological Survey Map, 1 inch, London District (Drift edition), Sheet 4.

1889. WHITAKER, W.—"Geology of London," vol. 1. Mem. Geol, Survey.

1907. CHANDLER, R. H., and LEACH, A. L.—"Excursion to Dartford Heath." Proc. Geol. Assoc., vol. xx, p. 122.

1907. NEWTON, E. T.—"Note on specimens of 'Rhaxella-Chert' or Arngrove Stone from Dartford Heath." Proc. Geol. Assoc., vol, xx., p. 107.

1912. CHANDLER, R, H., and LEACH, A. L." On the Dartford Heath Gravel and on a Palaeolithic Implement Factory," Proc. Geol. Assoc. vol. iii. p. 102.

Images[edit]

Excursion to Dartford Heath, May 17th 1913[edit]

List of photographs[edit]

Excursion to Dartford Heath, May 17th 1913[edit]

Page 31 P804557 Wansunt Gravel Pit in Dartford Heath Gravel. Excursion to Dartford Heath, May 17th 1913.
Page 31 P804558 Wansunt Gravel Pit in Dartford Heath Gravel. Excursion to Dartford Heath, May 17th 1913.
Page 31 P804559 Wansunt Gravel Pit in Dartford Heath Gravel. The ferruginous clayey base ?Iron pan? of the Dartford Heath Gravel resting on iron-stained Thanet Sand. Excursion to Dartford Heath, May 17th 1913.
Page 31 P804560 Wansunt Gravel Pit in Dartford Heath Gravel. Excursion to Dartford Heath, May 17th 1913.
Page 33 P804561 Excursion to Dartford Heath, May 17th 1913.
Page 33 P804562 Contorted Gravel and Sand. Excursion to Dartford Heath, May 17th 1913.
Page 33 P804563 Excursion to Dartford Heath, May 17th 1913.
Page 33 P804564 Crater pit near Bowman's Lodge. Excursion to Dartford Heath, May 17th 1913.