Stops Of Interest: Eastern Newfoundland, Terra Nova Park Area
- Dover Fault granite, Maccles Lake road
- Mixtite, Sandy Cove, Eastport area
- Ochre Hill lookout, Terra Nova
- Red beds near Port Blandford
- Keels slate deposits
1. Dover Fault granite, Maccles Lake road
The Dover Fault separates the Central Zone from the
Eastern Zone (see Plate Tectonics panel and Stop 60). Movement along the fault crushed the rocks
in the fault zone, creating finer grained, pulverized rocks called mylonite. There is an impressive
outcrop of mylonitized granite along the Maccles Lake Road. Turn south off the TCH toward the
old Alexander Bay Station; this turnoff is 2.4 km west of the Glovertown overpass. (For those
travelling east, the sign for gas stations at Glovertown is at this turnoff.) Take the first left (0.4 km),
and stop just short of where a power line crosses the road at a small pond (after about 0.5 km). The
exposure of ice-polished mylonite is on the right.
The original, pink granite intruded banded metamorphosed sedimentary rock, which
has also been mylonitized. Note the small knots of pink feldspar in the granite, with bands
of darker minerals (mainly black mica) wrapped around them. Small folds and faults affect
the banding.
Note also how glaciers during the last ice age polished the entire outcrop as they
moved across it. Striations and grooves are especially easy to see on the dark part of the
exposure. The striations cross the rock at an angle of about 60 to the fault and indicate the
direction in which the glaciers travelled.
2. Mixtite, Sandy Cove, Eastport area
Sandy Cove is a delightful place, with excellent exposure
of rocks that represent a chaotic slumping of sea-bottom sediments. Drive to Eastport on
Route 310, and turn right for Sandy Cove. In the middle of the community, turn right at the
T-junction; follow this road for 0.9 km as it narrows, park near the last house and walk to the
shore, taking the left fork in the track.
The rocky shelf consists of gritty, brown-weathering mudstone and sandstone
containing blocks of white-weathering, grey, thinly bedded shale, siltstone and sandstone.
Some of the blocks are several metres in length, and the bedding in many of them is folded
chaotically. This mixture of different rock types is called mixtite. The deposit is a result of
massive slumping of fresh, soft sediments down an undersea slope in Late Proterozoic time.
The large amount of water contained in unconsolidated sediment allows it to travel for long
distances down relatively gentle slopes.
Taking the right hand fork in the woods track will lead you out onto Sandy Cove
Point, which is also composed of mixtite. To the north, across Sandy Cove, is a bank of sand
and gravel 35 m high. This is part of a delta that was formed by a river of glacial meltwater
flowing into the sea from the depressed land surface between 12,000 and 14,000 years ago
(see Glacier panel).
3. Ochre Hill lookout, Terra Nova
Ochre Hill Lookout is the highest point in this part of Terra
Nova National Park, and provides a spectacular view of the park terrain, especially from the
added elevation of the fire tower. To get there, drive the 3 km from the TCH, or park part
way up and take the walking trail. There are several lookouts built in the vicinity of the fire
tower, with steps up the steeper bits. The rock surface is cleanest beside the tower itself.
The rock forming the hill is resistant, red, Late Proterozoic conglomerate. It consists
of well-rounded pebbles in a gritty red matrix. The pebbles are mostly red volcanic rock.
4. Red beds near Port Blandford
A large roadcut through Late Proterozoic red beds is located
on the TCH, 2.6 km south of the south entrance to Terra Nova National Park, or 3.5 km
north of the Port Blandford turnoff. The best way to view the exposure is to stand on the
northeast side of the road and observe the folds in the large face across on the southwest side,
then turn and look more closely at the material on your own side.
On the southwest side, the layers have been folded into large upright folds. Beyond
the ends of these folds, the rocks are crushed and chaotic. The red beds are mainly sandstone
and siltstone, but at the left end of the exposure there are some green sandstone beds
indicating a change in environment during deposition. Later white quartz veins are mostly
parallel to the bedding.
5. Keels slate deposits
To see the slate at Keels, drive via King's Cove on Route 235 through some
of the most ruggedly beautiful scenery in Newfoundland (84 km from the TCH). The
community of Keels is underlain by Cambrian slate, which is red and green, and finely
laminated. To see cliffs of slate that have been sampled for their commercial potential, turn
right at the Harbour View Grocery in the middle of the community, and continue to the end
of the road. Please respect the private property you must cross at the end of the road.
Walk on beside the fence and follow the path to the bluff above the water. All around you
is red slate, with nearly vertical cleavage. Slate is metamorphosed shale in which flakes of
platy minerals (mainly mica) grew parallel to each other as the rock was compressed. The
rock now splits readily along cleavage planes parallel to the millions of tiny mineral flakes.
Drive back to the main road through the community, where there are old houses, used
only in summer, and a small cove with a beach. Again, please respect the old buildings. The
slate is all around you, and you can see how the homeowners used it for foundations, steps,
roofs and walls.
This series of web pages provides an introduction to the publication
below, which can be ordered from the
Geological Association of
Canada 
Newfoundland and Labrador Traveller's Guide to the Geology
Edited by: S. Colman-Sadd and S.A. Scott, 91 pp. + map, 1994
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