Reservoir & production engineering data review & analyses of the Whicher Range tight gas sands

Abstract

The Whicher Range Field is a tight sand gas reservoir located on shore in the southern Perth Basin. Gas in place estimates range up to 5 TCF and there is an expectation that commercial recoveries are possible. A total of 5 wells have been completed and tested extending over a period of about 35 years. Multiple stimulation jobs were performed on some of the wells, but none has been successfully tested so far. The objectives of the study were to review well data and evaluate well productivity issues in this field to gain some appreciation of why production rates are significantly lower than expectations, and investigate possible remedial strategies to achieve viable gas production rates. The reservoir is a complex formation of stacked fluvial sand bodies that are stratigraphically and structurally compartmentalized. They exhibit very low porosities and extremely low permeabilities. Poor quality and the limited quantity of data impacted on the output value of some investigations, thus results are qualified. The need to acquire good data for the assessment of tight gas sand reservoirs is highly stressed.