CHAP. XLIII 
THE GABBROS OF SKYE 
347 
Torridon sandstone by a fault, it seems most probable that the change has 
been mainly due to the influence of the acid rock. 
In the Blath Bheinn group of hills the relations of the gabbro to the 
bedded basalts have recently been mapped in detail by Mr. Harker during 
the progress of the Geological Survey of Skye. He lias observed that, allow- 
ing for irregularities of form, the mass of gabbro obliquely overlies the basalts 
as a great sheet, not necessarily due to a single intrusion, which dips towards 
the west. He has found the rock to vary from a coarse gabbro to a diabasic 
type, and to vary also in mineralogical constitution, becoming in places very 
rich in olivine, though the banded structure is here only exceptionally 
developed. North of Garbh Bheinn the gabbro is much crushed and the 
Fig. 338. — Sketch of Banded Structure in the Gabbros of the hills at the head of Loch Scavaig. 
outlying patch to the north of Belig is in part a crush-breccia. Mr. 
Harker remarks that similar brecciated structures are common among the 
granophyres of the Bed Hills, and that it is sometimes difficult to dis- 
tinguish their structure from that of the true volcanic agglomerates. 
Besides the main area of gabbro in Skye, a great many small detached 
bosses, sills and dykes lie further east on the flanks of the Eecl Hills. One 
of the best marked of these detached areas forms a conspicuous crag on the 
east side of Strath More, immediately to the north of Beinn na Cro. It 
consists of beds of coarse gabbro, with others of dolerite intercalated in an 
outlier of the plateau-basalts, and is traversed by veins from the granophyre of 
the glen, as well as by the usual north-west basalt dykes (Fig. 349). It appears 
to be a marginal portion of the main gabbro area separated by the intrusion 
of the great granitoid boss of the Bed Hills. On the north-eastern side of 
