USING PLAY-BASED EXPLORATION TO DEFINE PLAY FAIRWAYS FOR THE PETREL SUB-BASIN, BONAPARTE BASIN, AUSTRALIA

Play-based exploration is an industry best practice, a structured approach for evaluating all relevant play elements that brings the exploration focus back to the play. It allows for geologic innovation and inclusion of geological possibilities within basin exploration and a quantification of risk and uncertainty of play segments. Only at the regional play level can all the geologic factors be mapped and integrated. In order to assess the risk within a play, the play is subdivided into several key risk factors: reservoir presence and effectiveness, top seal presence, trap presence and effectiveness, and charge (i.e. source rock presence and effectiveness of carrier beds). In the evaluation of the Petrel Sub-basin, part of the Bonaparte Basin in Australia, four play intervals (the Permian, Upper Carboniferous, Middle Carboniferous, and Upper Devonian to Lower Carboniferous) were identified and evaluated using this technique. Well failure analysis on 34 wells, gross depositional models, and gravity maps were data sources used to provide quantifiable information for mapping. Results for the well failure analysis were captured and entered into Player software, an ArcGIS extension. For each of the play intervals, individual composite risk segment (CRS) maps were generated using the key risk factors. By overlaying the CRS maps, a composite CRS (CCRS) map was generated illustrating the fairway for the play interval. Each of the four CCRS play interval maps was overlain generating a single basin-scale play fairway map. This simple, yet powerful, technique aids in hydrocarbon exploration at the play level; however, these maps have sharp boundaries between risk fields which were defined by use of imprecise data, but it is an effective method for standardizing basin-scale hydrocarbon exploration.