This paper summarizes the results of the modeling studies to determine the production performance of multiply fractured horizontal well completed in tight sand or Shale formations. A commercial reservoir simulator was utilized to model both single and a dual porosity reservoir with multiple layers. The results were utilized to investigate the flow regimes for horizontal wells with one or multi-stages of hydraulic fracturing stimulation. The impact of reservoir and fracture parameters on the flow regimes and the production performance was also investigated.

The objective of this study was to conduct a modeling study to determine the production performance of multiply fractured horizontal well completed in Shale formations and to investigate the impact of hydraulic fractures on the production performance of horizontal wells in ultra-low permeability formations. A commercial reservoir simulator was utilized to model both single and a dual porosity reservoir since both hydraulic fractures and natural fractures play significant roles in well performance of the low permeability reservoirs. The adsorbed gas component was also included in the models. The single and a dual porosity models were utilized to investigate the flow regimes for horizontal wells with multi-stages of hydraulic fracturing stimulation. History matching with actual production from Marcellus Shale wells was utilized to determine the basic model parameters. The results indicated the presence of number of different flow regimes. The hydraulic fractures appear to dominate the early production performance. The impact of reservoir and hydraulic fracture parameters on the flow regimes as well as the production performance and gas desorption were also investigated. The results can be utilized to investigate the feasibility horizontal wells with multiple hydraulic fractures and optimize the production from the shale formations.

The results of the modeling studies to determine the production performance of multiple fractured horizontal wells completed in shale formation has been summarized in this dissertation. A commercial reservoir simulator was utilized to model both single and dual porosity reservoir (with and without adsorption) with multiple layers. The impact of reservoir characteristics including natural fractures and hydraulic fractures properties on the production performance were investigated. In addition, the results were utilized to investigate the flow regimes for horizontal wells with one or multiple hydraulic fractures. Flow regime identification in low permeability reservoirs is extremely critical to evaluate performance of the horizontal wells. In this research, a number of possible flow regimes were identified using both log-log plot of inverse of the flow rate and its derivative versus time. They included linear, tri-linear (second linear), and pseudo-steady state. In addition, Decline Curve Analysis (DCA) and Production Type Curves (PTC) were also considered in this study to confirm the observed flow regimes and their production behavior. The results of this study will provide an understanding of flow behaviors in low permeability reservoirs. Understanding of the flow behavior can then be used to predict production from low permeability reservoirs such as Marcellus shale. iii ACKNOWLEDGEMENTS This dissertation is the result of my momentous journey in obtaining a doctorate of philosophy degree in Petroleum and Natural Gas Engineering (PNGE) at West Virginia University (WVU). I would like to express my gratitude towards certain outstanding individuals for helping make this dissertation a success. My sincere gratitude is to my academic advisor, Dr. Kashy Aminian, for his support during my studies at WVU. I really appreciate his help, patience, and guidance during my stay at WVU. His assistance was invaluable to me and undoubtedly a memorable experience. Looking to the future, one of my goals is becoming as good an advisor to my mentees as Dr. Kashy has been to me. In addition, I would also like to extend my appreciation to Professor Sam Ameri, Chairman of the PNGE Department, for his endless support during the course of my stay at WVU. Being more than just a professor to me, his advice always motivated me to thoroughly complete my research work. He greatly educated me regarding various beneficial scholastic endeavors as both an undergraduate and graduate student at WVU. I remain extremely indebted to Professor Sam Ameri for his continuous support and relentless assistance. Special thanks to Dr. Ilkin Bilgesu, for his consideration and patience during my education at WVU. He has been continuously helpful during my education at WVU.

Single-point test results can be used to obtain information regarding the degree of damage in gas wells in the gas storage reservoirs. Single-point test is neither timeconsuming nor costly to determine the productivity of a well. Furthermore, flow stabilization times would be short in high permeability gas storage reservoirs. Generally, a four-point test is conducted first to establish the deliverability relation. After some period of time, namely one year, a single-point test could be conducted. The results of the single-point and four-point tests can then be compared in order to identify any alteration in well performance. The objective of this research is to develop a methodology to determine skin factor by using a single-point test. In this work, the impact of formation permeability on determination of skin factor is studied for two cases, including transient radial and linear flow. The impact of non-Darcy flow is also considered in these cases. The results of this study are summarized by a series of correlation to evaluate skin factor from a single-point test. iii ACKNOWLEDGMENTS T his thesis is th e resu lt o f m y jou rn ey in o btainin g a M aster's d egree in Petroleum and Natural Gas Engineering. I would like to express my appreciation and gratitude to some people for helping me to make this thesis successful. First of all, I would like to express my gratefulness to my academic advisor Dr. Kashy Aminian, for his support over the last few years of my studies at West Virginia University. I really appreciate his help during my stay at WVU. His help meant a lot to me and it is memorable.