Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/437

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la Eigg the intrusive sheets at the hase of the volcanic series are much less strikingly exhibited than in Skye, Raasay, and Mull. Some good sections occur, however, at the north end. In the lowest group of the Oolitic series, as exposed on the shore and on the low cliff to the east of Blarmor, there is an abundance of thin sheets of anamesite, which, sometimes coincident with, sometimes traversing the bedding-planes of the shales and limestones, harden the strata along the line of contact. At that locality the succession of the rocks is somewhat obscured by the effects of some large landslips ; and similar disturbance extends all along the eastern flanks of Beinn Bhuidh. In one of the streamlets, coming down from that side of the plateau,

Fig. 4. Section of Interbedded and Intrusive Volcanic Rocks, on the East Coast of Eigg.

1. Sheet of intrusive basalt, 4 to 6 feet thick.

2. Sheet of fine-grained anamesite, 2 to 4 feet thick.

a. Calcareous pale yellow shelly sandstone (Oolite).

b. Columnar fine-grained anamesite or basalt, traversed by intrusive sheet (2).

c. Dull amorphous fine-grained anamesite.

d. Pale grey porphyrite.

near the Rudh nan tri Chlach, and which is known as the Ault na horsta mian, more than twenty intrusive sheets of dolerite, anamesite, or basalt may be counted among the shales and limestones. They are sometimes mere thin horizontal veins, not six inches thick ; and they

igneous rocks of Trotternish, in Skye, must thus be abandoned (see Quart. Journ. Geol. Soc. vol. vii. p. 104). I adopted his views in my first examination of Skye ; and my reference of the volcanic rocks of Skye to an Oolitic date must likewise be set aside (Trans. Roy. Soc. Edin. vol. xxii. p. 648 ; see also Proc. Roy. Soc. Edin. vol. vi. p. 72, where this change of view is indicated).