Jurassic basalt lava flows above soft sedimentary rocks form a ridge with a steep south-facing escarpment and a shallower north-facing dip-slope (see Figure 25). Cliffs of columnar basalt rise from wide wave-cut platforms along the Fundy shore. Semiprecious minerals occur within the basalt. The coastal forest gives way to hardwoods at higher elevations. Diverse and interesting rocky shore fauna are present on the Fundy coast, and relict arctic-alpine flora are found at Cape Split.
Geology and Landscape Development
On the southern side of the Bay of Fundy lies a steep-sided ridge (cuesta) which rises to more than 225 m at its eastern end and slopes to near sea level in the west.
The ridge is composed of several basaltic lava flows which dip northwest towards the Bay of Fundy at a shallow angle. They form the southern rim of a tilted spoon-shaped trough which underlies the bay. The rounded up-tilted eastern side of the trough can be seen in the curve of Scots Bay. The basalt in the lower western part eventually disappears under the water beyond Brier Island (District 810).
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The highest elevations and most dramatic scenery are found on North Mountain, particularly at Cape Blomidon where Cape Split sweeps around into the Minas Basin. The steep southern escarpment of the ridge may represent a fault line; the shallower northern side is a dip slope. The shore from St. Croix Cove to Cape Split provides a rich ground for mineral collecting because fresh rock is exposed each year after the winter storms.
Wind gaps through the ridge are found at Parkers Cove and Delaps Cove. These represent the abandoned lower valleys of rivers that flowed northwards from central Nova Scotia into the present Bay of Fundy and were captured by the Annapolis River. Digby Gut is the drowned lower valley of Bear River.
The emergent shoreline is smooth, exposed, and rocky with little coastal sediment.
The number of flows varies along the length of the ridge. Up to seventeen have been counted at Digby Gut, but only two can be seen along Digby Neck. The total thickness has been estimated at 300 m. Layers of green grit are found between the flows. These represent the weathered surface of the underlying flow and are easier targets for erosion than the massive flows; thus the basalt pile appears banded.
Basalt lava flows exhibit interesting features that reflect their volcanic origins:
- Amygdules: Gas bubbles trapped in the lava are filled with minerals over time, for example, agate, amethyst, jasper and zeolite minerals such as stilbite and heulandite.
Coastal erosion has cut tidal platforms 100-300 m wide along the Fundy shore, above which rise vertical sea cliffs. The columnar jointing can best be seen along this shoreline. Overlying the basalt is the Jurassic Scots Bay formation in which fossil fish and dinosaur footprints can be found. These sediments are present in six small inlets in Scots Bay.
Glacial ice moved across the Basalt Ridge both southwards and northwards at different times. The best evidence of south flow are pebbles of basalt found up to 200 km away along the South Shore. Basalt pebbles are very common in stony areas of the Annapolis Valley. Evidence of northward movement of glacial ice is provided by occasional boulders of granite, presumably from the South Mountain, which are scattered across the top of the Basalt Ridge. These were deposited late in the last glacial period when the South Mountain acted as a local ice centre (Unit 451). Deposits of glacial gravel are found along the Basalt Ridge at various points. The post-glacial emergence of this area is recorded in the raised beaches found at 40 m above present high tide near Digby and at 30 m on Brier Island.
The Basalt Ridge owes its prominence not only to the resistant nature of basalt but to the fact that it overlies soft, erodable sediments. The southern side of North Mountain has a steep scarp slope where these softer rocks have been carved out to form the Annapolis Valley. Along Digby Neck these same sediments have been removed to below sea level to form St. Marys Bay. Erosion is actively narrowing the Basalt Ridge on the Fundy side, although the energy of wave attack is diminished by wave-cut platforms. St. Marys Bay is more sheltered.
The southern boundary of District 720 follows a tertiary watershed divide across the top of North Mountain. Streams drain in a parallel pattern, directly into the Minas Channel. Gene pools of first- and second-order streams are isolated. Productivity is greatest where they originate on the higher elevations. The streams flow down the slopes quickly, but they are straight and small and have little erosive power. The area is heavily wooded and surface water is cool.
Soils in this District are fairly shallow when developed from the underlying basalt. Rock outcrops as ridges parallel to the coast. The main soil derived from basalt is Rossway, a shallow, well-drained silt loam; this soil is associated with Roxville, a poorly drained sandy loam found in depressions. On the plateau along the crest of the Basalt Ridge a fine sandy loam appears. This soil, called Glenmont, developed from a mixture of basalt and red Wolfville Till, which originated north of the Basalt Ridge. Finer-textured Wolfville soils (not drumlinized) occur between Harbourville and Victoria Harbour. A large area of Middleton soil (moderately well-drained, sandy clay loam) is found between Mount Hanley and Arlington West. Small patches of Kingsport and Nictaux soils, developed from water-deposited sands and gravels, are also found in this area. Along the Fundy Shore some areas of excessively drained loamy sand (Gulliver series) have formed on wave-washed gravels.
The District is unusual because earthworms are found in large numbers in the woodlands and their activity has incorporated the surface "mull" into the mineral soil.
A much-disturbed version of the coastal forest is found at lower elevations in this District. Shade-tolerant hardwoods occur at higher elevations, where they may be above the cold air from the Bay of Fundy. Red Spruce is more common here than along the Atlantic coast, and White Spruce is also found throughout, often seeding in abandoned fields. Away from coasts, the spruce, fir, pine forest with maple and birch gradually turns into Sugar Maple, Yellow Birch, and American Beech at higher elevations.
Rare arctic-alpine and uncommon Alleghanian plant species are found in the Cape Split/Blomidon area. Seaweed growth (e.g. Laverbread) is extensive at the west end of the District but decreases eastwards as the silt content of coastal waters increases. Almost no salt marsh is found along this part of the coast.
The Basalt Ridge provides mostly forest habitats with few lakes or wetlands. It supports a dense population of deer, but few bear or bobcat. Small-mammal diversity is moderate. The Basalt Ridge funnels the movements of migratory birds, particularly hawks and owls, as they head towards Brier Island in the fall. This funnelling may also occur with migratory bats which cross the Bay of Fundy or Gulf of Maine en route to their wintering areas. The exposed basalt along the shoreline provides good intertidal habitat with well-marked zones and large tidepools. Shells of subtidal molluscs and crustaceans are often found near wharves where lobster traps have been emptied. Some weir fishing is done.
The North Mountain provides spectacular views of the Annapolis-Cornwallis Valley and the Minas Basin at lookoffs along its southern escarpment. On the north-facing dip slope, lack of relief and paucity of settlement often yield landscapes of indifferent quality. However, where higher-quality soils (CLI classes 3 and 4) have encouraged larger blocks of cleared farmland (e.g., West Glenmount, Burlington, Mount Hanley, Mount Rose), north-facing routes present impressive yet curious panoramic views, as if the traveller were being tipped gently but inexorably into the wide Bay of Fundy. The opposing shores of the Chignecto peninsula and New Brunswick's Caledonian highlands, which seem to float on the bay, add to the illusion. The vertically cliffed coastline is punctuated by "hollows" or "vaults" of eroding stream-valleys. Squeezed in at the mouths of larger brooks are delightful fishing hamlets such as Baxters Harbour, Halls Harbour, and Harbourville.
Many of the coastal communities along the Basalt Ridge focus on fishing as an economic base, concentrating on
lobsters and weir-fishing. The latter requires very large net walls to catch fish trapped by ebbing Fundy tides. Small farms are a feature of parts of this landscape, as is forest exploitation. In the nineteenth century, tide-powered grist mills operated at Moose River and Parrsboro. The agates, amethyst, and zeolites found on cliff faces are world famous and every summer attract visitors who come to collect. Cape Split and Cape Blomidon feature dramatic landscapes with hiking trails, impressive scenery, and a provincial park that attracts recreation and tourism. Mi'kmaq Kluscap (Glooscap) legends are associated with this area.
|Cape Split trail
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Sites of Special Interest
- Cape Split (IBP Proposed Ecological Site 65) - primarily deciduous woodlands with rich herbaceous flora; rare minerals and semiprecious minerals found in amygdaloidal basalt
- Cape Blomidon - steep sea cliffs
- Cape Blomidon to St. Croix Cove - good mineral localities
- Digby - raised beach 40 m above high tide; Digby Gut; drowned lower valley of Bear River
- Point Prim - wide, wave-cut platform
- Scots Bay - limited occurrence of the Scots Bay Formation in a few small coves in the only accessible portion of Jurassic sediments that underlie the Bay of Fundy; fossils include algal stromatolites, plants, fish, and dinosaur footprints and bones
Provincial Parks and Park Reserves
- Valley View
- Cottage Cove
- Blomidon Lookoff
- Baxter Harbour
- Cape Split
- Cape Blomidon beach
- The Lookoff
- Route 360 south of Garland (view of the Valley)
- Valley View Provincial Park
- Point Prim
|T3.2 Ancient Drainage Patterns|
| Terrestrial Glacial Deposits and Landscape Features|
|T10.12 Rare and Endangered Plants||
|H5.3 Cliff and Bank|
|H6.1 Hardwood Forest (Sugar Maple, Yellow Birch, Beech Association)|
|H6.2 Softwood Forest (Spruce, Hemlock, Pine Association)|
|H6.3 Mixedwood Forest (Spruce, Fir, Pine-Maple, Birch Association)|
|Associated Offshore Units|
|912 Outer Fundy|
|913a Minas Basin|