Page:Quarterly Journal of the Geological Society of London, vol. 35.djvu/842

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PROF. E. HULL ON THE DINGLE BEDS AND

those in the neighbourhood of Killarney, next those of Kenmare, and lastly those south of Glengariff. I shall briefly describe the results of our examination of these districts in the order above named. A detailed description will be unnecessary, so much having already been written on the subject by authors already quoted, as well as by the officers of the Survey.

Fig. 1.—Section along the Western Coast of Dingle Promontory, showing the connexion of the Dingle Beds with the fossiliferous Silurian below.

Quarterly Journal of the Geological Society of London, Volume 35, 0842.png

a. Slates &c. with fossils (Wenlock).

b. Beds of volcanic ash and lapilli, with felstone and bands of slate.

c. Purple slate and brecciated beds.

d. Fine-grained purple grits and slates, passing up into grey and yellow slates and calcareous sandstones with Ludlow and Wenlock fossils.

e. Grey and brown and purple slates and concretionary sandstones.

* Fossiliferous localities.
† Supposed base of Dingle beds.

a. Dingle Section. (Figs. 1 & 2.)

The whole series is admirably laid open in the coast cliffs extending from Sybil Point to Slea Head, a distance of six miles. The bottom beds are probably of Llandovery age, upon which follow representatives of the Wenlock and Ludlow beds as far as Clogher Bay. Owing, doubtless, to a large fault, these beds are repeated to the south of Clogher Head, where they form a section of a dome or inversion, as represented on the horizontal section prepared by Mr. Du Noyer. Nevertheless from Carrigcarn, opposite Carhoo, southwards there is an unbroken section commencing with the representatives of the Wenlock beds up into the Glengariff grits of Mount Eagle and Slea Head, which strike across the intervening sound into Great Blasket Island. This section, which has been very carefully measured and observed, shows a thickness of about 10,000 feet of strata, and is as follows, adopting the designation of the beds as given by the Geological Survey:—

Section in Dingle Promontory.
(Beds in descending order.)

Old Red Sandstone and Conglomerate resting discordantly on several of the underlying beds (Sybil Head, Kinard Hill, Bull's Head, &c).

"Dingle beds."
1. Red and purple slates of Ventry and Dingle Harbour, surmounted by conglomerate of Parkmore.
2. Glengariff grits.—Hard massive greenish and purple grits, sometimes pebbly, and containing flaggy and ripple-marked beds.
3. Purple and greyish slates with bands of grit inter-stratified.