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Rank wildcat wells in Ultra deepwaterD- present some of the greatest challenges today. Decision making during drilling is challenging due to a lack of offset well data. 3D Surface seismic data has significant uncertainty from the translation of two-way time to horizon depths which further induces risk into the predrill pore pressure model. This paper looks in detail at how the utilization of a high-tech logging while drilling suite in the execution of a rank wildcat enabled key drilling decisions to be made, reducing risk and time vs. depth plan the well. Seismic while drilling technology guided drilling in each section from spudding to total depth by allowing up to 600 m look ahead. This reduced target depths uncertainty from +/-100 meters to less than +/-5meters. Furthermore it permittedallowed this complex S-shaped well trajectory to avoid accidental penetration into the first target avoiding well control situation, placing the 13 3/8?? casing shoe safely above the first target, 80m shallower than planned. This ensured an increased mud weight window for the 12.25?? section. In the 12.25?? section, Formation Pressure While Drilling Technology was added to the Seismic and Sonic technologies to calibrate the pre drill pore pressure model. This was critical due to a narrow mud weight. The acquired formation pressures coupled with while drilling petrophysical data allowed for the pore pressure to velocity transform and normal compaction trend lines to be calibrated reducing the uncertainty in the pore pressure model ahead of the bit. Uncertainty in depth of targets and modeled pressure ramps ahead of the bit were further reduced with the Seismic data.

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The four offshore basins of Namibia are highly underexplored despite one of these basins containing the large undeveloped Kudu gas field. Substantial discoveries elsewhere on both sides of the South Atlantic conjugate margin have brought new focus on the potential of the entire West African margin. With billion barrel fields in neighbouring Angola to the north, attention has turned to the relatively neglected potential of the Namibian offshore basins. Following basin reconnaissance using sparse 2D seismic grids, 3D seismic data is being acquired over many of the most attractive blocks awarded in Namibia. This study describes the results of a fast-tracked integrated project delivering a dual-sensor 3D broadband seismic and seismic attribute analysis to provide increased understanding of petroleum systems and risk elements, prospective resource volumes and highgrading and de-risking drilling targets.

The Kentucky Geological Survey (KGS) at the University of Kentucky is conducting a research project funded by the Gas Research Institute (GRI) to study hydrocarbon production from the Devonian shale in eastern Kentucky. The primary objectives of this project are to develop an understanding of the relationship between local geology and hydrocarbon production from the Devonian shale, to create a comprehensive Devonian shale data base of well information, and to prepare an oil and gas report for each county in the study area. Project data have been compiled from the KGS oil and gas well record files, the GRI Eastern Gas Data System (EGDS), files from the U.S. Department of Energy (DOE), and records from cooperating oil and gas companies operating within the study area. Gamma-ray logs were found to be the most valid means of identifying the stratigraphic units within the Devonian shale. Temperature logs are used to locate gas shows in order to determine which interval to stimulate. The combined use of the temperature log to find the gas shows, and the gamma-ray log to identify which stratigraphic unit the gas is coming from, is an invaluable method for determining the treatment interval. The two most common methods of stimulating production in Letcher and Knott Counties are explosive shooting and hydraulic fracturing. Comparison of the initial potentials both before and after treatment indicates that hydraulic fracturing is preferable to borehole shooting for improving production in the Devonian shale. Data compilation in Letcher and Knott Counties is complete. An extensive data base of information on the 1,412 Devonian shale wells in Letcher and Knott Counties has been compiled. Using this information, detailed stratigraphic cross sections within the Devonian-Mississippian shale sequence have been constructed, as well as structure, isopach, and isopotential maps. Analysis of the maps and cross sections suggest two relationships. There appears to be a direct relationship between areas of high Devonian shale initial open-flow potential and 1) the location of shallower hydrocarbon production, and 2) the location of linear features determined from LANDSAT imagery. The preliminary results of this study provide the petroleum industry with valuable guidelines for the future exploration of natural gas in the Devonian shales of eastern Kentucky.