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    This digital dataset represents the modelled outputs of the three-dimensional distribution of sandiness in the Paskapoo Formation, Alberta, Canada. Sand-abundance values were determined from log analysis of water-well lithologs and petroleum exploration downhole-geophysical logs, specifically gamma-ray logs. We derived the sandiness values by calculating the average sandiness in 25 m thick slices above the base of the Paskapoo Formation in a borehole and by assigning the average value (P50) to the midpoint of each slice interval. Alberta Geological Survey Bulletin 66 provides detailed descriptions of the methodology. We tested the borehole sand-abundance values in a 3-D variogram prior to kriging in a regular block model consisting of cells with dimensions of 1000 m on the x and y planes and 25 m in the z (elevation) direction. Values of modelled sandiness range from 0 (absence of sand) to 1 (100% sand) and are assigned elevations based on two datums: 1) a stratigraphic level corresponding to the height of the midpoint of each respective 25 m thick slice interval above the base of Paskapoo Formation, and 2) the elevation of the midpoint of the slice above sea level. Importing the modelled results of sandiness into model viewing software, such as Voxler, permits the user to generate three-dimensional isovalue plots illustrating the differences in distribution and geometry of aquifers as different cutoff or threshold criteria are applied. The dataset also enables one to delineate the regional lithostratigraphic units nested within stratigraphically complex rock formations.

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    The dataset includes subsurface stratigraphic picks of the tops of the Horseshoe Canyon/Wapiti and Battle formations in the west-central Alberta Plains (Townships 15 to 67, Ranges 16W4 to 3W6) made from wireline geophysical well logs. The dataset supplements Alberta Geological Survey Open File Report 2011-08, which describes the methodology. We screened the well data to detect errors resulting from deviated wells, as well as incorrect well-header ground and kelly bushing elevation data. Statistical methods identified local and regional statistical outliers, which were examined individually.

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    In 2002 the Alberta Geological Survey initiated a project to scan and digitize water well geophysical logs from Alberta Environment and Sustainable Resource Development (ESRD) water well data holdings. Casual and summer student staff scanned hard copy logs systematically by NTS mapsheet starting with the Cold Lake area. Scanned logs were digitized into Log ASCII Standard version 2 by Divestco Ltd. This data release consists of 8,763 LAS files, comprised mostly of resistivity logs, and a tab delimited index file. About 1% of the LAS files also contain a natural gamma log. The API number (APIN) in the log header refers to Alberta Environment's water well identifier number used at the time the logs were digitized. There are 205 records where the API number starts with 900. We were unable to confidently match the log file surface location to an AENV location for these records. The approximate aerial coverage is from latitude 49 degrees to 56 degrees N and from longitude 110 degrees to 120 degrees W. This work concluded in March, 2007.