File:The Quarterly journal of the Geological Society of London (12645690655).jpg

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. .DeC. 17,
Vale of St. John westward to Keswick, bound the Skiddaw slates of
this portion of Cumberland.
The southern portion of this area rarely exhibits the rocks in situ.
The Skiddaw slates in this district occupy Flaseow Moor, a large
tract of barren country lying between the Keswick and Penrith lload
on the north, and the base of the hills just referred to on the south.
Two streams, having their origin among the greenish-grey rocks on
the south, intersect this moory district in their course to the Glen-
dermaken River, which flows into the Greta near Threlkeld. The
most easterly of these streams, called Troutbeck, after passing over
the greenish-grey rocks, reaches the moory country, and begins to
exhibit in its course the Skiddaw slates. In a small brook which
flows into Troutbeck from the west, these slates are considerably
contorted, but have predominant S.S.E. dips. A short distance
above the hamlet of Troutbeck this inclination is well seen, the
angle being 40°; and a gritty quartz-rock, strongly impregnated
with iron-pyrites, is here seen associated with the Skiddaw slates.
For a considerable distance below this hamlet, through the moor,
no exposures of rock occur ; but when the stream reaches near to
the Keswick Road, parallel to which it flows for some distance, we
have good sections of the Skiddaw slates, principally on the line of
strike. The stream in this portion of its course is called Gills-beck,
and here the Skiddaw slates, which are thin-bedded and of a dark
colour, have prevailing N.N.W. dips. Intercalated with the strata
are masses possessing the structure known as cone-in- cone, a feature
which accompanies the Skiddaw slates in some other localities. In
some portions of this section there are great contortions in the bed-
ding, and quartz-veins are abundant, running along the lines of the
contortions.
N.N.W.
Fig. 3. — Section from Matterdale to Uldale (12 miles).
S.S.E.
a. Skiddaw Slates, b. Granite, c. Green slate and porphyry.
d. Felspathic Traps. e. Carboniferous rocks.
Westward from this stream we have the Skiddaw slates exhibited
in the course of another brook, which also traverses Flascow Moor
from the south. This, which is known as Mosedale-beck, rises from
the northern flank of Great Dod, and its upper portion is likewise
over the greenish-grey rocks. The junction of these with the Skid-