Regional Data Analysis to Better Predict Drilling Success: Brushy Canyon Formation, Delaware Basin, New Mexico

Abstract

Abstract Incomplete or sparse information introduces a high level of risk for oil exploration and development projects. "Expert" systems developed and used in several disciplines and industries have demonstrated beneficial results in modeling the decision making process of knowledgeable experts. A state-of-the-art exploration "expert" tool using a computerized data base and computer maps generated by neural networks, is being developed using fuzzy logic, a relatively new mathematical treatment of imprecise or non-explicit parameters. Analysis to date includes generation of regional scale maps of aeromagnetic, gravity, structure, thickness, and production data for the target Brushy Canyon Formation in the Delaware Basin, New Mexico. For each regional scale map, data attributes were also computed to look for more subtle trends. These attributes include directional first and second derivatives, dip azimuth and magnitude, and azimuth and magnitude of curvature. These data were mapped and gridded to a 40 acre spacing, the current well spacing for Delaware pools in New Mexico, and compared to average monthly production in the first year for Delaware Brushy Canyon wells. The geophysical and geologic data covers 60478 bins (3780 square miles), of which 2434 of these bins have oil, gas and water production data. Using a new fuzzy ranking tool each data attribute was ranked for its ability to predict production potential at these well locations. The highest ranked attributes are gravity dip-azimuth, second latitude derivative of thickness, longitude derivative of gravity, and longitude derivative of structure. These attributes are being used to generate a production potential map for the Delaware basin, using neural networks and expert systems, at the scale of 40 acres. Such a map would be a useful tool for evaluating the potential of infill, step out, and wildcat wells in the Delaware basin, both at reservoir and regional scales. Introduction Expert systems are computer programs that are designed to make decisions similar to the manner in which a human expert would. In the past expert systems have been primarily restricted to medical and industrial applications, but with DOE support an expert system to prospect for oil is now being developed to automate and accelerate prospect development for the Brushy Canyon formation in the Delaware basin. Expert systems operate by developing rule sets that can be used to answer questions related to the problem at hand, in this case prospect evaluation. Since prospect generation data often contains non-crisp data, such as "low porosity" or "high on structure", the expert system will necessarily allow fuzzy inputs. The approach taken is to accumulate all available public domain data and incorporate them into online databases, which can be accessed by the expert system. A primary goal was to develop a map of production potential based on available regional data from which the expert system could add or detract to each prospects estimate of risk. This paper discusses the development of this production potential map.