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In short, yes. This case study illustrates that the application of a thorough geotechnical workflow incorporating many new and advanced techniques can assist in exploration business case decision making. Is an exploration drilling decision made lightly? A workflow incorporating 3D seismic processing, AVO inversion and stratigraphic framework studies involving high-resolution biostratigraphic and chemostratigraphic analyses was used to assess the prospectivity of an exploration permit near giant gas fields in the offshore Northern Carnarvon Basin. The primary reservoir is the prolific Triassic Mungaroo Formation fluvio-deltaic sediments, and secondary reservoirs include mid-Jurassic marine sands. 3D seismic reprocessing xcombined a newly acquired broadband seismic dataset into a multi-survey multi-azimuth PSDM volume that conditioned data for input to an AVO inversion. New petrophysics and rock physics analysis and modelling on regional well data were then calibrated with the AVO inversion to statistically derive lithology and fluid prediction volumes. These data were used in conjunction with reservoir paleo-stratigraphy studies to derive a subsurface model for reservoir distribution and hydrocarbon prediction. A two-stage risking process was applied to each prospect that objectively applied risk based on the seismic amplitudes. This enabled a more accurate risked-volume assessment, combined with the ability to assess a prospect portfolio covering different plays. The resultant interpretation identified issues with interpretations made on vintage data that would not have been easily identified without undertaking these studies. The integration of these assessments resulted in an unfavourable exploration drilling business case and a decision not to renew the permit.

The Granite Wash formation in the Texas Panhandle is an active horizontal drilling trend where high initial gas rates combined with rich condensate yields create a rewarding investment opportunity for operators. The Granite Wash formation has been a drilling target for over 30 years but development accelerated rapidly after November 2004 when 20-acre downspacing was approved in the Buffalo Wallow field. In the years 2004-2008, vertical infill development was actively pursued with operators using an "assembly line" methodology that concentrated on cost reduction to achieve economic success. When soft gas prices made vertical wells economically challenging, operators turned to horizontal wells to improve the trend's economics. Previous papers [Edwards (2010), Ingram (2006)] have explored optimizing completion technology in the Granite Wash so this paper's objective is to find solutions to questions about initial production, rate decline, and liquid yields by examining the reservoir and fluid properties. The paper uses techniques developed for generalized tight gas sand reservoirs and applies Granite Wash formation data to create focused solutions. The data presented show the horizontal wells' high initial rates can be correlated to the offset vertical well performance and the initial production declines are defined by linear flow. In addition, a technique for optimizing the number of completion stages is presented and the condensate yields are explained using an Equation of State (EoS).