Hydrologic properties of coal-beds in the Powder River Basin, Montana. II. Aquifer test analysis

Hydrologic properties of coal beds in the Powder River Basin, Montana I. Geophysical log analysis

“…and is in reasonable agreement with that determined for the Flowers-Goodale coal at Well 2 and reported by Weeks (2004) as being roughly 5!10 K6 m K1 . This latter value is based upon the early-time response of an aquifer test and represents the component of specific storage corresponding to a fractured medium.…”

“…In the companion paper, Weeks (2004) reports on the results of a multi-well aquifer test conducted in Well 2 across an isolated, lowermost coal interval (Flowers-Goodale coal; see Fig. 5).…”

“…13. Wellbore deviation plots for pumped well (Well 2) and three nearby observation wells used in aquifer test (see Weeks, 2004). Polar diagrams follow wellbore trajectories in horizontal plane (m) with respect to depth; target centers represent well locations at surface.…”

“…Coal cores and siliciclastic rock cores were recovered for laboratory measurements of various physical properties and an aquifer test was performed by pumping one well while monitoring three nearby observation wells to determine the hydraulic properties of an isolated coal bed (Weeks, 2004). In addition, comprehensive sets of geophysical logs were obtained to locate coal beds, identify and orient structural features such as cleats and bedding planes, quantify various elastic properties of the formation, and estimate aquifer specific storage.…”

“…This paper focuses on the analysis and interpretation of these geophysical logs in order to characterize the stratigraphy of the coal beds and interbedded siliciclastic rocks, to investigate possible correlations between structural patterns and the local stress field, and to examine the implications of these results in terms of the groundwater flow system. General hydrologic properties of the coal are based on the analysis of an aquifer test reported in a companion paper by Weeks (2004).…”