Phase II of Play Fairway Analysis for the Eastern Great Basin Extensional Regime, Utah: Status of Indications

摘要

Building upon previous investigations in the region, additional geological, geophysical and geochemical data have been acquired and analyzed over promising composite common risk (CCR) areas identified in the central eastern Great Basin, Utah, in order to focus prospectivity and prepare for drilling recommendations. These areas of interest are near the Twin Peaks rhyolite field, high heat flow areas north of the producing Cove Fort system, and geophysical structure beneath the Crater Knoll area off the northeast flank of the Mineral Mountains. Additional data included MT site fill-in, structural mapping and analysis using high-resolution imagery, gravity and on-ground mapping, Nodal 3C passive seismic collection, and passive 3He surveying. Heat source and permeability potential are again expressed in terms of their individual common risk segment (CRS) maps, with a color scheme using green for most favorable (low risk) and red for least favorable (high risk). Diverse data types are united through the technique of probability kriging, which establishes prospectivity thresholds for each data type and then computes probability of exceeding that threshold over the PFA area. Modified CRS and CCRS maps are compared with previous versions to highlight tighter prospectivity focus. In doing so, the prospectivity threshold for heat was increased significantly to narrow the targeting. Priority areas remain but are more focused in the northern Cove Fort - Dog Valley and Twin Peaks rhyolite center.