Hydrogeological implications of paleo-fluvial architecture for the Paskapoo Formation, SW Alberta, Canada: a stochastic analysis

Autor: Erick R. Burns, Paul R. J. Wozniak, Derald G. Smith, Stephen E. Grasby, Masaki Hayashi, Laurence R. Bentley, Anthony P. Hamblin
Rok vydání: 2010
Předmět:
Zdroj: Hydrogeology Journal. 18:1375-1390
ISSN: 1435-0157
1431-2174
Popis: Fluvial systems tend to deposit sediment in well-defined relational geometries and in vertically and laterally repeating patterns. These sedimentary deposits are preserved to varying degrees depending on how much the fluvial system reworks the deposits. The Paskapoo bedrock aquifer system in southern Alberta, Canada, was deposited in a foreland depositional basin during uplift of the Rocky Mountains, and both the geomorphic model and field evidence indicate that the upper 100 m of the local aquifer system contains well-preserved, highly connected paleo-channels and associated overbank deposits. In order to evaluate the value of different types of data, a simplified stochastic-numerical groundwater flow model was developed to examine the sensitivity of results to model parameters. Parameters examined include: fraction of the formation made up of channel sands; meander and sinuosity factors; width-to-depth ratios of preserved channels; and crevasse splay conductivity. In all cases examined, the system exhibited anisotropic behavior with the along-channel flow direction being the most permeable and the vertical direction being least permeable. In general, the strongest control on the resulting effective anisotropic hydraulic conductivities was channel fraction, but geometric factors that control between-channel connectivity (e.g., channel sinuosity) had an appreciable effect on the across-channel flow direction effective permeability.
Databáze: OpenAIRE