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532 Chignecto Plains
| Geology & Landscape | Fresh Water
| Soils | Plants | Animals Cultural Environment | Sites of Interest | Topics & Habitats |
Geology and Landscape Development
The geology varies in this Unit. The northern part is more like Unit 581. However, most of the area is underlain by Cumberland Group strata made up of grey sandstones, siltstones, and shales. In places the sandstone is coarse; in others it is fine-grained and has been used for millstones and building stone. The strata have been thrown into open folds, which become tighter close to the Cobequids (Unit 581). Some of the anticlines in the east of Unit 532 have been eroded, exposing the underlying Early Carboniferous or Mississippian Windsor Group deposits. In these places the folding is accentuated by the movement of salt, which has risen through the strata to form domes.
Glacial deposits mask most of the Chignecto Plains, and the strata can best be seen along the shore of Chignecto Bay. The most important section lies in the 15 km between Minudie and Shulie, where a vertical section of 4,444 m of Cumberland Group strata is exposed. These strata form part of a shallow basin that extends from Minudie to the Cobequids (Unit 311). Towards Shulie the younger strata begin to slope upwards towards the base of the Cobequids.
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| Joggins, Cumberland County Click to enlarge |
The seams can be traced inland for 30 km but gradually coalesce towards Springhill. Four outcrop at River Hebert, two each at Maccan and Chignecto. At Springhill the section of coal-bearing strata is 800 m thick and contains 31 coal seams.
The coal seams in the Cumberland Basin formed in an unstable environment characterized by subsidence, plant growth, inundation, and burial by mud and sand, more growth, and so on in a cyclic pattern. The coal seams tend to grade into shaly coal and coaly shale, vertically and laterally. They are structurally weak and dangerous to work at depth.
At a well-known locality near Joggins is a classic coastal section of Late Carboniferous strata. Between Coal Mine Point and Lower Cove, fossilized tree stumps of Lepidodendron and Sigillaria can be seen in their original growth positions. Siltstones rich in plant debris occur, as well as limestones containing the shells of freshwater and brackish water pelecypods and ostracods. Amphibian and reptile bones and the tracks of giant arthropods have also been found. Sedimentary structures in the strata include ripple marks, wave ripples, current bedding, mud cracks, rain prints, and channel deposits.
Outcrops of sandstone bedrock create a bedrock-dominated landscape west of River Hebert. To the east of the river, extensive sandy tills mask the bedrock, particularly in the Chignecto Game Sanctuary and in the Sand River area, creating a distinct landscape.
Freshwater Environments and Coastal 
Wetlands
The watershed predominantly consists of numerous second- and first-order rivers and streams, flowing in a modified trellis pattern. The Unit is dissected by a secondary watershed boundary. To the south, the Shulie River and East Apple River fall within separate tertiary watersheds. River Hebert and its tributaries dominate the landscape to the north. Numerous short streams have direct shoreline drainage. There are extensive bog systems, and numerous tidal marshes occur along the coast.
Soils
Grey and brown sandstones and reddish brown conglomerates have provided the parent materials for the dominant soils of this Unit. Shulie, imperfectly drained Springhill, and poorly drained Economy soils have developed from sandstones. For the most part they are relatively shallow, stony loams. West of the River Hebert are large areas of very shallow soils. The haphazard interference of bedrock with soil drainage creates an intricate pattern of imperfectly and poorly drained depressions.
Plants
This Unit falls within the Maritime Lowlands Ecoregion of Loucks' Red Spruce, Hemlock, Pine Zone and has been heavily
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| Chignecto, Cumberland County Click to enlarge |
In 1912, C.D. Howe made the following observations on soil-forest relationships in this fire-devastated area: "The sandy plain is covered with small sandy knolls from one to two feet above the little depressions which are from a yard to five yards in diameter. The bedrock is a hard, fine-grained sandstone which, in general, is apparently not more than two feet below the surface. The vegetation is composed of wire birch and scattering jack pine, which escaped the fire, with an undergrowth of blueberry, sheep laurel and hair cap moss. The damp pockets contain purple laurel (rhodora), Labrador tea and sometimes spruce seedlings. Jack pine seedlings are frequent on the knolls."
Animals
This Unit is mostly a mix of forest habitats, with few agricultural areas. Cliffs and intertidal sands and muds occur along the coast.
Moose have responded to the regenerating forest following Spruce Budworm infestation by developing one of the more vigorous populations in mainland Nova Scotia. Deer do not winter along Chignecto Bay, which is exposed to westerly winds. In hard winters, deer are absent from the Chignecto Game Sanctuary, preferring to migrate south.
There are few lakes or wetlands, and beaver and otter densities are low. Bobcat, coyotes, and Red Fox are common. Raccoons are found near the scattered agricultural settlements. Black Bear occur in moderate numbers. American Shad, Gaspereau, Sea Lamprey, and Atlantic Salmon enter River Hebert to spawn in fresh water. Gaspereau are known to travel as far as Welton Lake, where they spawn along the lake shore. Salmon also enter Apple River. The edges of River Hebert, Shulie River, Kelly River, and Atkinson Brook provide interesting habitat for a variety of wildlife.
Mud flats towards Minudie are important feeding areas for shorebirds that roost on the New Brunswick shore at high tide. Smaller numbers roost at Mill Creek and at West Apple River during high tides. Approximately 100 Black Ducks winter at Apple River estuary.
The Northern Ringneck Snake has been seen at Chignecto Game Sanctuary.
Cultural Environment
The first record of mining in the Cumberland Basin dates to the early eighteenth century, when the "old French Workings" were mined at Joggins. Acadians had once extracted coal from the cliffs here. The Joggins mine was completely closed in the 1960s, and the River Hebert coal mine closed in 1980. A coal-fired steam turbine plant was operated at Maccan. Good harbours are not found on the shores of the Cumberland Basin, so fishing activity is limited. In the 1970s, when the harnessing of the Fundy tides was under serious consideration, the Cumberland Basin was designated as a candidate site for a tidal power generating station. The forest cover in this Unit is variable as a result of past disturbances. Pines may average higher than in other areas, but the Red Pines planted on the sandy areas (After major fires early in the twentieth century) are more prominent than naturally regenerated stands. Forests facing Chignecto Bay were severely affected by Spruce Budworm in the late 1970s and 1980s. The extensive forest harvest areas where infected forest stands were salvaged provide good moose habitat.
- Joggins (Coal Mine Point to Lower Cove) - coastal exposure of Upper Carboniferous (Pennsylvanian) sediments and coal seams of the Cumberland Basin coalfield; these cliffs are famous for their fossils, which include trees, reptiles, and amphibians; features include sedimentary structure, a classic Late Carboniferous section, coal seams outcropping along the shoreline of Chignecto Bay, and two district tills, different in colour, containing boulders of granite and limestone; this is a protected site, under consideration as a world heritage site because of its scientific interest
- Chignecto Game Sanctuary
- Shulie River (IBP Proposed Ecological Site 2) - Red Spruce stand
- Chignecto River (IBP Proposed Ecological Site 3) - pure stand of Red Pine
- Parrsboro Geology Museum
Provincial Parks and Park Reserves
Proposed Parks and Protected Areas System includes Natural Landscape 19.
Scenic Viewpoints
- River Hebert, both sides - dyked farmland
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