Box 7 Use of Well Record Data for Identification of Surficial Aquifers in Nova Scotia, Canada
In Nova Scotia, the provincial well record database (Nova Scotia Environment, 2020) has been used extensively for research and interpretation purposes, in part due to the limited resources of the small province to collect subsurface data. A few examples include provincial scale hydrogeological characterization (Kennedy and Drage, 2009), the use of static water level information reported on well logs to identify seawater intrusion vulnerability (Kennedy, 2012), the analysis of spatial patterns of water well type (e.g., shallow drilled, dug wells, deep drilled) to identify drought vulnerability (Kennedy et al., 2017), and the spatial analysis of temporal static water level trends and groundwater quantity issues recorded on well records to identify areas of potential groundwater stress (Kennedy and Utting, 2011).
The Nova Scotia Well Logs database has also been used to map and characterize surficial aquifers. For example, well log data can be used to construct stratigraphic cross-sections as shown in Figure Box 7-1a (Kennedy and Utting, 2011) or map the potential extent of surficial (Kennedy, 2014) aquifers suitable for groundwater supply development based on a spatial analysis of well log stratigraphic information (Figure Box 7-1b).
Figure Box 7–1 – a) Use of well log data to interpret geological cross-section and thickness of buried sand and gravel layer (from Kennedy and Utting, 2011); and b) GIS process to automate the delineation of the potential extent of surficial aquifers from well log data whereby wells intersecting surficial aquifer materials are grouped and then a smoothed polygon is created to envelop the points. Red dots indicate the presence of surficial aquifer materials that are more than 3 m thick as detected in well logs whereas smaller black dots indicate the absence of surficial aquifer materials (from Kennedy, 2014).