Abstract

Current drilling methods are not well adapted to the detection and reliable evaluation of oil-producing formations. The very principle of rotary drilling requires the sealing off of permeable horizons, and it is difficult and sometimes impossible to restore their permeability. Electric logs are poor indicators of saturation, and mudloggers are inaccurate and not always reliable. Cores are normally flushed and do not give true values of oil content. Even drill stem tests do not provide a good estimate of the barrels per day a formation will produce. If we are going to the expense of opening a hole into a formation, we ought to be able to get a positive test and not have to rely on interpretations of electric log and core data to tell whether it contains commercial oil. Development of new tools should be directed not solely towards faster, or even cheaper drilling, but towards those methods that result in the best oil wells.