Salisbury Formation fractured bedrock aquifer

Hydrogeological Context

Version Metadata
f64ad8c6-548f-4f2a-927d-a28f36a47c67
Project
Carboniferous Basin

Datasets

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Salisbury Formation fractured bedrock aquifer unit description

Update:2014-02-04
In ascending order, the geological groups are: basement complex and Horton, Windsor, Mabou and Cumberland Groups. The latter includes Boss Point, Cumberland undivided and Salisbury formations. The internal stratigraphy of these units is complex and often laterally discontinuous. Salisbury formation is composed of mudstone, siltstone and fine-grained sandstone. It is covered by a till unit which extends over the entire area. It is covered by a silty matrix till unit. This till feature involves low hydraulic conductivity, suggesting a poor percolation of surface water. Salisbury formation has poor recharge rates. The silty matrice of the till allows a better confinement of the aquifer, causing a good protection against contamination from the surface. Despite the moderate hydraulic conductivity of the hydrogeological unit, the aquifer potential is poor (almost considered as aquitard). The groundwater quality is good, but it has some aesthetic problems. Concentrations of chlorine, fluoride, iron, manganese and sodium are high. Locally, there are some problems of nitrate, total hardness and other metal traces.
Physiography
Hydrogeological regionMaritime Bassin
Hydrogeological context
ReliefThe terrain of Salisbury formation is flat, characterized by low altitudes. These vary between 0-50 and 50-100 m. The land has a few gentle slopes (2-5%) along the Petitcodiac River.
Area889.00 km2
Lithology
DescriptionIn ascending order, the geological groups are: basement complex and Horton, Windsor, Mabou, and Cumberland Groups. The latter includes Boss Point, Cumberland undivided and Salisbury formations. The internal stratigraphy of these units is complex and often laterally discontinuous. The Horton Group consists of a sequence of sedimentary and volcanic rocks that is overlain by the marine limestone and evaporates strata of the Windsor Group. The marine beds are overlain by thick assemblages of continental origin, which correspond to the Riversdale-Mabou and Cumberland groups. Salisbury formation is composed of mudstone, siltstone and fine-grained sandstone. It is covered by a silty matrix till unit.
Source
Aquifer
AquifersList of aquifer Salisbury rock aquifer

Unit properties

Bedrock aquifer media
Typical value:porous - fractured
Description Groundwater circulates within the bedrock through fractures and interconnected pore spaces between the individual grains. Since fractures have a much higher permeability than the matrix around them, groundwater flows predominantly through fractures.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Confinement
Typical value:confined - semi confined
Description The system can be considered semi-confined, but confined and unconfined conditions can be found, mainly depending on the till layer composition.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Surficial sediment thickness
8 m
Description In New Brunswick, the till thickness varies between 0-20 m. The average thickness is 8 m for New Brunswick and Nova Scotia.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Well depth
38.1 m Range: [0 to 183] m
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Groundwater depth
4.7 m Range: [0 to 28.5] m
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Surficial unit hydraulic conductivity
6.5E-9 m/s
Description The hydraulic conductivity is weak because the till matrix is silty in this location.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Bedrock hydraulic conductivity
Range: [1e-06 to 5e-05] m/s
Description The hydraulic conductivity is above 1E-6 m/s and below 5E-5 m/s
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Regional precipitation
1099 mm/y Range: [947 to 1201] mm/y
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Regional evapotranspiration
Range: [345 to 440] mm/y
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Regional recharge
40 mm/y
Description The unit has the second lowest recharge rates of the aras.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Hydrogeological unit potential
Typical value:Poor aquifer or aquitard
Description It has one of the best aquifer potential of the area.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Aquifer vulnerability
Typical value:Low
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin
Groundwater Quality
Description Water has high concentrations of chloride, fluoride, iron, manganese, and sodium. The pH is alkaline. Locally, there are some problems of nitrate, hardness and other metal traces.
Source Hydrogeological Atlas of South-Central Area of the Maritimes Carboniferous Basin