Contributions of Gas Adopting-Desorption in Marcellus Shale for Different Fractured Well Configurations

Gas adsorption in the shale system is vital for accurate predictions of gas production and estimating subterranean reserves, particularly in the Marcellus shale. In this shale system, gas adsorption also significantly influences the total recovery and reserve estimations. However, there hasn't been a comprehensive analysis of the adsorption characteristics across various Marcellus shale regions. This study delves into the contributions of distinct gas adsorption phenomena within the Marcellus shale, especially in relation to different fractured well configurations. The aim is to discern the production responses of reservoirs under diverse adsorption traits and well designs. To achieve this, a Marcellus shale model under stress is numerically simulated using existing literature data. Subsequently, six samples detailing adsorption characteristics from different regions of the Marcellus shale are incorporated into the model, ensuring a precise representation of the adsorption dynamics. The study then evaluates two well configurations, namely, fractured vertical and horizontal, to understand gas desorption's effect on production. The results reveal that gas desorption can enhance overall production by up to 5% in a single-stage multi-clustered fractured horizontal well. The desorption impact is relatively low in the initial production stages but becomes significant over prolonged periods. Additionally, gas desorption is more pronounced in areas with a larger surface area and expansive fracture networks. The study concludes that fractured horizontal wells are ideal for maximizing gas desorption in the Marcellus shale, offering invaluable insights for formulating efficient production strategies tailored to adsorption characteristics in the Marcellus shale.