Sketch of the Geology of the Arctic Regions. 9 
but the ridges are destitute of vegetation. On the west banks of 
the river, red granite extends from the Copper Mountains to the 
sea, where it forms mural precipices on the coast. ‘The main shore, 
for sixty miles east of the Coppermine River is a low shelving grav- 
elly beach. Eastward of this beach trap rocks re-appear, and 
form an exceedingly sterile and rocky coast. The islands near this 
coast abound in cliffs of greenstone and dark brown claystone por- 
phyry. The whole country is barren, one ridge of rocks rising 
above another, with stony vallies between, without a trace of vegeta- 
tion. Red and grey granite rise occasionally into acute and craggy 
peaks fifteen hundred feet high, alternating with low naked ranges of 
gneiss. In one instance a vein of galena was found enclosed in the 
gneiss, which is often intersected by perpendicular precipices of trap 
rock, claystone porphyry, iron shot clinkstone, porphyry and earthy 
greenstone. 
Continuing east, light red sandstone and bluish grey slate appear. 
Tron shot amygdaloid, and a reddish amygdaloid, enclosing beautiful 
pebbles of chalcedony and carnelian, with imbedded masses of jasper, 
are found on Barry’s island. On the coast, gneiss re-appears at short 
distances, with occasional lofty pinnacles of granite, frequent beds of 
granite and hornblende gneiss, and hexagonal crystals of hornblende 
imbedded in the gneiss with scales of mica. 
According to Dr. Richardson, the new red sandstone formation 
prevails on the Arctic sea coast, from the mouth of the Coppermine 
River in W. long. 116° eastward to Cape Turnagain, which is in W. 
long. 109°, N. lat. 69°. The gneiss formation is next in extent, and 
runs parallel and within the red sandstone, extending from the sea to 
Fort Enterprise in 65° N. lat. presenting the genuine “ Barren 
Ground” with its dreary precipices and hills. 
The average direction of the strata, just mentioned, is north west 
and south east always inclined towards the horizon, the mean angle 
exceeding 45°. Granite, sienite, gneiss, mica slate and clay slate 
occur throughout this tract, with their usual relations and positions, 
as in other parts of the globe. Gneiss is the most extensively distri- 
buted, always attended with a scanty vegetation, and generally the 
most desolate sterility. The bowlders which crown the summits of 
the hills on the “ Barren Grounds” are generally a variety of granite.* 
* Are not these “Barren Grounds” a continuation of the desert which ranges at 
the foot of the Rocky ee south of Athabasca ? 
Vou. XVIL—No. 
