DRILLING REPORT Wired drill pipe for HPHT RSS for large boreholes in soft sediment Heat-induced drill pipe failures RESERVOIR CHARACTERIZATION WIRELESS SEISMIC ACQUISITION 54TH REEDHYCALOG RIG CENSUS LNG MARKET REPORT RESERVOIR CHARACTERIZATION Porosity partitioning and permeability quantification in vuggy carbonates

A pilot study of 13 wells in Means oil field of the Permian basin, West Texas, established porosity-permeability relationships for the Permian Queen, Grayburg and San Andres formations. The optimized workflow used borehole image and conventional log processing with calibration to core data. This approach allowed the quantification of porosity and perme-ability heterogeneity in vuggy carbonate facies in the field. Queen formations, with supporting production from Wolfcampian and Leonard-ian strata. These formations are predominantly dolomitized marine carbonate platform successions, with the exception of the lower Grayburg, which is a mixed carbonate-siliciclastic reservoir facies. Typical completion strategies are to fracture-stimulate the tighter Grayburg reservoirs and to perforate and acidize the better San Andres reservoirs. Following 31 years of primary recovery with 40-acre well spacing, the field has been developed on 10-to 20-acre well spacing in the active-flank waterflood areas and 10-acre well spacing in the updip areas where tertiary recovery by CO 2 injection is conducted. Recovery efficiencies vary from about 14% in the waterflood area to 42% in the CO 2-flood area. The original carbonate platform has been structurally modified into a north-trending asymmetric anticline with a steeply dipping eastern limb and a gently dipping western limb. Outer-shelf, shelf-margin and middle-shelf facies dominate the San Andres formation. The Grayburg is predominantly middle-shelf facies characterized by laminated dolomite with interparticle and intraparticle porosity and minimal vuggy porosity. Thin anhydrite horizons may occur, interbedded with finely laminated fluvial and eolian sandstone. Anhydritic dolomite is also a common facies. Perme-ability in both the dolomite and sandstone is usually less than 1 mD, but can be as high as 10 mD. The lower Grayburg is dominated by middle-to inner-shelf facies. The upper Gray-burg is dominated by evaporite and dolomite facies. During deposition of the San Andres formation, shallow-water car-bonate sedimentation dominated the central basin platform region, producing a thick carbonate sequence that later became completely dolomitized. The Queen formation is domi