Geology and Hydrogeology of Faults on Cape Breton Island, Nova Scotia, Canada: an overview

Cape Breton Island provides a hydrogeological view into the roots of an ancient mountain range, now exhumed, glaciated, and tectonically inactive. It exhibits deep crustal faults and magma chambers associated with formation of the Appalachian mountain belt and the Maritimes Basin during the Paleozoic, as well as Mesozoic rifting relating to the opening of the Atlantic Ocean. Cenozoic exhumation brought these features near surface and into the active groundwater flow field where they were impacted by glaciation and fluctuating sea level. The faults have been important from a societal viewpoint in development of municipal groundwater supplies, controlling inflows to excavations, hydrocarbon exploration, quarry development, and geotechnical investigations. Conceptual models presented here outline fault control on groundwater flow based on seven case studies. Future research should focus on basin-bounding faults in support of managing their role in aquifer development and protection, mountain-front recharge, controlling large-magnitude springs, groundwater–stream interaction, and channel morphology. The hydrogeological importance of these faults has historically been underappreciated.

Download Full-text

The geology and hydrogeology of springs on Cape Breton Island, Nova Scotia, Canada: an overview

Atlantic Geology ◽

10.4138/atlgeol.2019.004 ◽

2019 ◽

pp. 137-161

Author(s):

Fred E. Baechler ◽

Heather J. Cross ◽

Lynn Baechler

Keyword(s):

Debris Flows ◽

Monitoring Program ◽

Debris Avalanche ◽

Hydrocarbon Exploration ◽

Future Research ◽

Mountain Range ◽

Flow Temperature ◽

Cape Breton Island ◽

Cape Breton ◽

Sphere Of Influence

Cape Breton Island springs have historically played a role in developing potable water supplies, enhancing salmonid streams, creating thin-skinned debris flows, as well as mineral and hydrocarbon exploration. Cape Breton Island provides a hydrogeological view into the roots of an ancient mountain range, now exhumed, deglaciated and tectonically inactive. Exhumation and glaciation over approximately 140 Ma since the Cretaceous are of particular relevance to spring formation. A total of 510 springs have been identified and discussed in terms of hydrological regions, flow, temperature, sphere of influence, total dissolved solids, pH and water typing. Examples are provided detailing characteristics of springs associated with faults, karst, salt diapirs, rockfall/alluvial systems and debris avalanche sites. Preliminary findings from a monitoring program of 27 springs are discussed. Future research should focus on identifying additional springs and characterizing associated groundwater dependent ecosystems. Incorporating springs into the provincial groundwater observation well monitoring program could facilitate early warning of drought conditions and other impacts associated with changing climate.

Download Full-text

The geology and hydrogeology of buried bedrock valley aquifers on Cape Breton Island, Nova Scotia: an overview

Atlantic Geology ◽

10.4138/atlgeol.2017.013 ◽

2017 ◽

Vol 53 ◽

pp. 301-324

Author(s):

Fred Baechler

Keyword(s):

Mountain Range ◽

Cape Breton Island ◽

Riverine Ecosystems ◽

Changing Climate ◽

Geological Processes ◽

Cape Breton ◽

Unconsolidated Sand ◽

Geotechnical Investigations ◽

Sand And Gravel ◽

The Impact

Buried bedrock valley aquifers are common across Canada, where multiple glaciations have buried both pre-glacial and Pleistocene valleys. These aquifers are becoming increasingly important as a supply of potable groundwater, for supporting aquatic habitat, and as part of strategies in adapting to a changing climate. However, in Canada, there are considerable knowledge gaps at national, regional, and local scales, such that many buried bedrock valleys remain unidentified or underexplored. Cape Breton Island provides a hydrogeological view into the roots of an ancient mountain range, now exhumed, glaciated, deglaciated, and tectonically inactive. Since the Cretaceous, a variety of geological processes have formed several buried bedrock valley aquifers over the island. These aquifers are important in providing municipal and commercial groundwater supplies, controlling mine dewatering, protection of salmonids, design and monitoring of waste disposal sites, and geotechnical investigations for infrastructure design. Of 150 sites assessed, 61% provided evidence of buried aquifers comprising unconsolidated sand and gravel of Cretaceous, Pleistocene, and Holocene ages. These sites provided the basis for five conceptual, 3-D hydrogeological block models. Three hydrogeological case studies provided further insight into the functioning of two of these models. Future studies should identify and characterize aquifers in high demand areas and/or those that support important riverine ecosystems. Research should focus on aquifer properties, groundwater-stream interaction, and the impact of changing climate with sea-level rise.

Download Full-text

The Ainslie Detachment: a regional flat-lying extensional fault in the Carboniferous evaporitic Maritimes Basin of Nova Scotia, Canada

Canadian Journal of Earth Sciences ◽

10.1139/e96-016 ◽

1996 ◽

Vol 33 (2) ◽

pp. 169-181 ◽

Cited By ~ 14

Author(s):

Gregory Lynch ◽

Peter S. Giles

Keyword(s):

Nova Scotia ◽

Hanging Wall ◽

Cape Breton Island ◽

Fine Grained ◽

Cape Breton ◽

Westerly Direction ◽

Maritimes Basin ◽

Highly Strained ◽

Planar Fabric ◽

Stratigraphic Succession

The Ainslie Detachment occurs near the base of the Carboniferous Windsor Group, forming a regional flat-lying extensional fault distributed across 10 000 km2. New mapping has delineated the structure through southwestern Cape Breton Island and into central Nova Scotia. Shearing is concentrated at the top of the basal Macumber limestone along its contact with overlying evaporites and younger allochthonous units. The highly contrasting rheologies of the formations created an anisotropic zone of weakness which acted as an upper crustal stress guide, stratigraphically controlling the trajectory of the detachment through the basin. The detachment is characterized by an approximately 3–10 m thick calc-mylonite zone, with an intense planar fabric featuring alternating very fine grained shear planes and coarser annealed layers. Coarser layers are boudinaged into pinch and swell structures, locally producing segmented augen. Highly strained intraclasts, ooids, and peloids, recrystallized carbonate boudins, and carbonate vein segments are included in the calc-mylonite as semirigid inclusions and rotated porphyroclasts. Thick zones of fault breccia straddle portions of the detachment and overprint the mylonite, demonstrating an evolution to brittle conditions during progressive shear. Listric faults in the hanging wall of the detachment feature a ramp and flat geometry, with an upper detachment occurring along the upper contact of the Windsor Group with the overlying Namurian Mabou Group. Locally up to 2 km of the stratigraphic succession has been removed, with faults cutting downsection in a westerly direction producing rollover in the hanging wall.

Download Full-text

Stratigraphic and geochemical constraints on the relative age of the Margaree Shear Zone in western Cape Breton Island, with implications for the early evolution of the Maritimes Basin

Atlantic Geology ◽

10.4138/2075 ◽

1996 ◽

Vol 32 (1) ◽

Cited By ~ 1

Author(s):

Gregory Lynch

Keyword(s):

Shear Zone ◽

Early Evolution ◽

Western Cape ◽

Cape Breton Island ◽

Relative Age ◽

Cape Breton ◽

Maritimes Basin ◽

Geochemical Constraints

Download Full-text

The near-surface geology of St. Georges Bay, Nova Scotia: implications for the Hollow Fault

Canadian Journal of Earth Sciences ◽

10.1139/e95-051 ◽

1995 ◽

Vol 32 (5) ◽

pp. 603-613 ◽

Cited By ~ 8

Author(s):

P. Durling ◽

K. Howells ◽

P. Harvey

Keyword(s):

Nova Scotia ◽

Seismic Reflection ◽

Deformation Zone ◽

Strike Slip ◽

Seismic Reflection Data ◽

Near Surface ◽

Cape Breton Island ◽

Deep Seismic Reflection ◽

Reflection Data ◽

Cape Breton

A formline contour map, which depicts the near-surface, structural configuation of the strata underlying St. Georges Bay, northeastern Nova Scotia, was made from bedding attitude data compiled in the coastal areas; apparent dips measured from single-channel seismic reflection data; and true strikes and dips calculated at survey track intersections. The geology interpreted from the formline map is characterized by northeast-striking faults and fold axes. The folds in the bay comprise broad, open synclines and narrow, tightly folded or faulted anticlines. Gravity and deep seismic reflection data suggest that the faulted anticlines are intruded by salt. Correlations from offshore to onshore suggest that the structures mapped offshore in the bay extend onshore. The onshore extensions of the faulted anticlines are mapped as faults, and their antiformal nature is subdued. They are locally associated onshore with Carboniferous Windsor Group outcrop. The offshore extension of the Hollow Fault, which is interpreted as a major northeast-striking, Carboniferous strike-slip fault, was mapped as a 1500–2500 m wide deformation zone, using deep seismic reflection data. Gravity lows coincident with the deformation zone are interpreted as being caused by salt intrusions. The trend of the Hollow Fault Zone suggests that this fault complex (and its associated strike-slip movement) continues on land near Mabou, Cape Breton Island. However, it does not appear to continue offshore along the northwest coast of Cape Breton Island, as previously suggested.

Download Full-text

Culinary tourism on Cape Breton Island

Canadian Food Studies / La Revue canadienne des études sur l alimentation ◽

10.15353/cfs-rcea.v6i2.333 ◽

2019 ◽

Vol 6 (2) ◽

Cited By ~ 1

Author(s):

Erna MacLeod

Keyword(s):

Tourism Destination ◽

Cape Breton Island ◽

Culinary Tourism ◽

Economic Significance ◽

Cape Breton ◽

Local Stakeholders ◽

Resilient Communities ◽

World Class ◽

Ecological Relations ◽

Developed World

Cape Breton Island is a well-known North American tourism destination with long-standing attractions such as the Cabot Trail and more recently developed world-class offerings such as the Cabot Links Golf Course. Tourism contributes significantly to Cape Breton’s economy, particularly since the mid-20th century as traditional resource-based industries have declined. In the 21st century, culinary tourism has become increasingly important to expand the island’s tourism offerings and to provide “authentic” tourism experiences. This study examines local-food tourism in Cape Breton to illuminate its cultural and economic significance. I conducted interviews with food producers, restaurateurs, government representatives, and tourism executives. I also consulted websites and policy documents and compared local stakeholders’ experiences and perspectives with official tourism strategies. Promoting culinary tourism raises questions of power, autonomy, inclusion, and accountability. My study accentuates possibilities for aligning economic and ecological goals to create resilient communities, foster equitable social and ecological relations, and establish Cape Breton as a culinary tourism destination.

Download Full-text