Pressure drawdown management (PDM) has been heavily studied in offshore and onshore environments as a way to improve the well productivity and in general Estimated Ultimate Recovery (EUR). There has been a great interest in this topic, especially in unconventional oil and gas reservoirs, where multi-stage hydraulic fracturing and horizontal well technology is used to enhance oil and gas production. Recent studies on Inflow Performance Relationship (IPR) of shale oil/gas reservoirs have shown that unmanaged pressure drawdown (UPD) can potentially impact well productivity and profitability in different ways. Hydraulic fracture conductivity impairment is an example and can occur through proppant crushing, embedment, and fine migration. Uncontrolled pressure drawdown can also cause geo-mechanical effect in high-pressured reservoirs. Aggressive pressure drawdown has shown detrimental impact to EUR, flow capacity, and economics of the wells in Haynesville, Eagleford, and Point Pleasant/Utica shales. Wilson (2015) used a coupled geo-mechanics model with a large Haynesville data set that showed that effective stress on fractures is influenced by operational changes, and managed pressure drawdown can improve gas recovery. Deen et al. (2015) also illustrated that aggressive pressure drawdown can damage a well's performance in the Eagle Ford, while conservative pressure drawdown can impact the near term economic value. In shale reservoirs the impact of pressure drawdown management on well performance and EUR is mostly related to pressure dependent permeability.

Unmanaged pressure drawdown has also shown rapid transition from transient flow to boundary dominated flow in unconventional gas reservoirs. There is a balance between the rate in which the wells are produced and economic feasibility of the wells over time. Optimal economic production rate must be found for each area. The goal of this study is to analyze well productivity between wells that use managed drawdown versus unmanaged drawdown in over pressured formations such as Utica/Point Pleasant. The production performance of the wells will be analyzed using various reservoir techniques including superposition plot, diagnostic plots, history matching, and decline curve analysis. In addition, economic sensitivity will be run to find out the incremental increase in EUR needed to justify the delay in production. The optimum economic rate to produce the reservoir while maintaining the integrity of the reservoir is the ultimate goal producing from shale gas reservoirs, which will provide the maximum value for the shareholders.

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