Estimating Specific Storage and Matrix Compressibility from Barometric Efficiency in the Southern Alberta Paskapoo Aquifer System

Abstract

Specific storage (Ss) and matrix compressibility (α) are fundamental aquifer properties which can be estimated by barometric efficiency (BE), a measure of well response to changes in barometric pressure. Five BE estimation techniques (amplitude ratio analysis, Clark method, Rahi method, graphical ellipse, and barometric response functions) are discussed and a standardized technique for estimating BE, pre- and post-analysis data conditioning (PPC) is described. It is shown that this technique can greatly improve the consistency of BE estimates and that small scale resolution errors rather than large scale noise may impact results the most. The PPC approach and an inter-quartile range filter are applied to data obtained from the Paskapoo formation and BE, Ss, and α estimates are derived (ranging from 3.9-99.5%, 8.3x10-7-1.7x10-5 m-1 and 1.6x10-11-1.7x10-9 Pa-1, respectively). It is demonstrated that the outlined techniques allow data from non-traditional sources (active pumping wells and legacy monitoring wells) to be employed.