Evaluation the methodologies of analyzing production and pressure data of hydraulic fractured wells in low permeability gas reservoirs "Tight Gas Reservoir"

This study has been conducted & Submitted in Partial fulfillment of the requirement of the Degree of Master of Science in the Department of Petroleum and Natural Gas Engineering at the College of Engineering, King Saud University, Riyadh, Kingdom of Saudi Arabia, Jumada II 1429H -June 2008GProduction data analysis approaches have advanced significantly over the past few years. While many different methods have been published in the literature, there is no single method that yields the most reliable answer. Analyzing production history and pressure data of a hydraulically fractured gas well in low permeability reservoir can be an effective way to estimate the well and reservoir properties. However, fractured gas wells in low permeability reservoirs represent a challenge to petroleum engineers. This is because of the presence of wellbore storage, formation damage and Non- Darcy flow effects around wellbore. This study uses an advanced production analysis package, Topaze, to evaluate the most applicable methods for use in determining well and reservoir parameters, and estimating the gas in place for hydraulically fractured gas wells in low permeability reservoirs. Field and simulated examples are presented to illustrate the evaluation of these methods. Results from this study show that modern methods such as Blasingame, Normalized Pressure Integral and the Flowing Material Balance are valuable analysis tools for production history and pressure data. Both pressure transient analysis and production analysis have been studied. The interaction of changing wellbore storage and Non-Darcy flow effects on the analysis of production and pressure data have been studied. Results show that using flowing pressure data in production analysis will be more representative and descriptive of the reservoir than using wellhead pressure data for gas well. Non- Darcy flow and mechanical skin effects in production analysis were defined and estimated using converted downhole pressure, while they were not observed in the wellhead pressure data interpretation