Any errors in the original data were carried into this dataset and no systematic checking of attributes from original data sources was undertaken.
Values for the fields "Perm_M2", "Cond_MS" and "Cond_MD" are truncated to three significant figures from the values received from the Temco MP-401 permeameter equipment.
Spatial locations for each borehole are unique, however multiple tests were conducted at different depths within the core, and some depths have been tested more than once. Therefore, record uniqueness is defined by using a combination of fields. This combination is Borehole, Test_Depth_M, and Perm_MD. All attribute data have been assigned values and were checked.
Permeability measurements were made using the same instrument for all tests (Temco MP-401 air-permeameter). Measurements were made by several people that were trained to operate the instrument. All permeability measurements have been converted to hydraulic conductivity using a consistent calculation described in the process step section of this metadata record.
The elevation of core hole locations was either specified in the source publication or determined by taking the land surface elevation from the 25 m Provincial Digital Elevation Model (DEM).
Where the source data specified the elevation, it was assumed to have been acquired using a GPS-based system.
Reference for the Provincial DEM is Alberta Environment and Parks (2015). Provincial DEM, digital topographic data; AltaLIS, URL http://www.altalis.com/products/terrain/dem.html, 25 m cell, Esri Grid format.
The Provincial DEM datum is NAD83, with an absolute accuracy determined by Alberta Survey Control Markers, and relative accuracy (depending on terrain) of +/- 5 m for X,Y & Z.
The calculation of test elevation was achieved by subtracting the test depth specified in the source publication from the elevation. Assuming that individual core samples range in length from 5 to 25 cm would add some additional vertical error, but less than the error associated with the elevation of the core hole location
This tabular data is a compilation of published permeability measurements made by Alberta Geological Survey staff members between 2004 and 2015. These data were only shown previously as part of figures and/or strip logs in report appendices. Measurements were made on rock cores for various projects described in the source reports.
Data collection details are provided in each source publication. Permeability measurements were made using an air-permeameter (Temco MP-401) that has a range of approximately 0.01 to 5000 millidarcies. This tabular data contains only measurements made perpendicular to the core axis to obtain horizontal permeability.
Permeability values are reported in units of millidarcies and metres squared. Equivalent hydraulic conductivity values are reported as metres per second and metres per day based on the following calculation:
K=kpg/u
where, K = hydraulic conductivity of sample (m/s); k = permeability of sample (m2); p = density of water (assumed to be 999.9 kg/m3); g = gravitational constant (9.81 m/s2); u = dynamic viscosity of water (8.9x10-4kg/ms).