Regresar

Unveiling stimulation fluid-driven alterations of pore architecture and transport property in Mowry Shale, Wyoming

Abstract:

Unconventional natural gas has emerged as a vital resource in meeting energy demands in recent times. Among these resources, the Mowry shale stands out as a significant source rock in Wyoming, boasting one of its largest unconventional hydrocarbon reservoirs. However, since 2009, production activities have shown lower-than-expected yields, despite the extraction of a substantial volume of condensate. This discrepancy is believed to be partly attributed to inadequate hydraulic fracturing designs, particularly those that neglect interactions among rock, formation brine, and stimulation fluid. These geochemical interactions have the potential to modify pore structures and hinder mass transport, which drives the imperative to understand the alterations induced by stimulation fluids in the Mowry Shale. In this research, Mowry Shale samples were allowed to react with two fluids. Initially, samples were exposed to formation brine for 15 days, followed by the injection of a stimulation fluid, for a total of 30 days. This systematic approach is aimed at simulating reservoir conditions and thereby assess the impact of stimulation fluids on pore architecture and transport properties. To this end, pre- and post-treatment characterization was conducted to ascertain changes in pore structure and adsorption capacity arising from rock-fluid interaction. Findings in this research shed light on underlying mechanisms governing shale reservoir behavior. By elucidating these fundamental processes, this research seeks to gain insights that inform optimal production conditions, thereby enhancing the commercial viability of exploiting resources within the Mowry shale. Ultimately, a deeper understanding of these issues will contribute to overcoming challenges associated with poor production and performance of shale reservoirs.