Predicting Horizontal Well Production Performance Using Type Curves

Abstract

Abstract Significant potential natural gas resources remain in low permeability marginal reservoirs of the Appalachian Basin. Horizontal well as an alternative to fractured vertical well, has a significant potential to enhance the recovery from the low permeability gas reservoirs. This paper addresses the potential contribution of horizontal wells to increasing the economic recovery from the low permeability gas reservoirs. The selection of horizontal well over vertical well in low permeability gas reservoirs must be based on engineering and economic feasibility evaluations. The accurate prediction of production rates is one of the most important variables for feasibility evaluation of horizontal wells. It is, therefore, desirable to develop and evaluate simple but reliable methods for predicting the production performance of the predicting the production performance of the horizontal wells. The production performance of horizontal wells completed in the low permeability gas reservoirs can be predicted by utilizing production type curves without the need for costly and time consuming computer simulations. The application of the production type curves and the issues concerning the production performance of horizontal wells in the low permeability gas reservoirs are discussed. In addition, pre-stimulation production date from a horizontal well in West production date from a horizontal well in West Virginia is compared with the predicted results from the type curves in order to evaluate the applicability of the type curves. Introduction Appalachian Basin is the oldest gas producing province in the country. As a result, the easier to province in the country. As a result, the easier to develop conventional reservoirs have been already discovered. Presently, gas production comes mainly from the low permeability marginal reservoirs. The development of the low permeability gas reservoirs requires innovative approaches to improve economics. Therefore, it is necessary to study and evaluate the new technologies that can increase the recovery efficiency from low permeability gas reservoirs. This paper addresses the potential contribution of paper addresses the potential contribution of horizontal wells to increasing the economic recovery from the low permeability gas reservoirs. The use of horizontal well technology to stimulate production is not a new idea. However, significant production is not a new idea. However, significant advances in drilling technology during the last decade have made it possible to drill and complete horizontal wells commercially. The horizontal wells are currently being considered for production enhancement in a variety of reservoirs. In general, the horizontal wells are believed to enhance the production in thin reservoirs, naturally fractured production in thin reservoirs, naturally fractured reservoirs, and reservoirs with good vertical permeability. permeability. In low permeability gas reservoirs, horizontal well which can be considered as a long controlled, infinite conductivity vertical fracture has a significant potential to increase the gas recovery. The selection of horizontal well over vertical well, however, must be based on technical and economic feasibility evaluation. One of the most important variables for feasibility evaluation of horizontal wells is the production rates. The objective of this study has been to develop and evaluate a reliable method for predicting the production performance of the horizontal wells without the need for costly and time consuming computer simulations. The general constant pressure solutions in the form of type curves have pressure solutions in the form of type curves have provided accurate predictions of the production provided accurate predictions of the production performance of gas wells in the past. Therefore, performance of gas wells in the past. Therefore, the production type curves that have been developed for horizontal wells can be utilized to predict the production performance of horizontal wells completed in the low permeability gas reservoirs of the Appalachian Basin. P. 321