Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
This paper outlines a methodology for constructing equation of state (EOS) descriptions and source rock fluid composition correlations to describe the fluid properties of entire unconventional plays, such as the Eagle Ford shale play and the Permian Basin's Delaware Basin Wolfcamp formation. This methodology is tailored to match the quality of the available data in each play. Sufficient reservoir fluid samples (either recombined companion surface separator samples or downhole fluid samples) with full pressure-volume-temperature (PVT) laboratory studies are required to span the range of fluids found in each play. These data provide the basis for tuning EOS parameters for C7+ pseudo-components and binary interaction parameters. Source rock fluid composition varies with thermal maturity of the reservoir. The most direct measure of thermal maturity is C7+ mole weight (MW) determined for fluid samples; however, in areas with unstable production, such as slugging or cycling wells, a three-month-average producing condensate/gas ratio (CGR) is utilized as the basis for correlating the composition. The resulting tuned EOS models and source rock fluid composition correlations provide fluid descriptions for forecasting models, well models, artificial lift design tools, and facility models. When combined with proprietary maps of source rock thermal maturity measures, the models discussed here can be utilized to estimate fluid properties for undrilled acreage.
This paper outlines a methodology for constructing equation of state (EOS) descriptions and source rock fluid composition correlations to describe the fluid properties of entire unconventional plays, such as the Eagle Ford shale play and the Permian Basin's Delaware Basin Wolfcamp formation. This methodology is tailored to match the quality of the available data in each play. Sufficient reservoir fluid samples (either recombined companion surface separator samples or downhole fluid samples) with full pressure-volume-temperature (PVT) laboratory studies are required to span the range of fluids found in each play. These data provide the basis for tuning EOS parameters for C7+ pseudo-components and binary interaction parameters. Source rock fluid composition varies with thermal maturity of the reservoir. The most direct measure of thermal maturity is C7+ mole weight (MW) determined for fluid samples; however, in areas with unstable production, such as slugging or cycling wells, a three-month-average producing condensate/gas ratio (CGR) is utilized as the basis for correlating the composition. The resulting tuned EOS models and source rock fluid composition correlations provide fluid descriptions for forecasting models, well models, artificial lift design tools, and facility models. When combined with proprietary maps of source rock thermal maturity measures, the models discussed here can be utilized to estimate fluid properties for undrilled acreage.
Evaluating EUR and production forecasting in multi-frac horizontal wells completed in unconventional shale reservoirs during early, exploration and appraisal stages is very challenging. With the absence of suitable production facilities to handle produced fluids, production data are limited to short flow backs and extended production for some key wells to early production facility (EPF). This method uses the flow capacity as an intrinsic parameter that captures and reflects the major drainage mechanism and recovery characteristics of the well within the unconventional reservoir. Thus, the flow capacity may serve as a reference parameter that can be estimated from early-time data. This parameter may have the ability to reflect the future production behavior of the well in terms of cumulative production through proportional comparison of flow capacity to EUR. To show applicability of the workflow, it was applied to an existing unconventional project and showed consistent results. The workflow incorporates RTA analysis for several wells to create a single correlation that describes the relationship between Ac√k and EUR. Plotting gas flow capacity (Ac√k), estimated during the early 3-4 weeks of flowback, versus the estimated EUR from modeling techniques showed a strong correlation. The proposed workflow is designed to estimate EUR for wells completed in unconventional reservoirs during the early phases of development, where there is no production facility to handle produced hydrocarbons and flow back period is limited to cleanup only. The advantages of the proposed workflow over the currently available methods are: (1) Incorporating several wells analyses to create a single correlation that describes the relationship between Ac√k and EUR (2) The ability to evaluate EUR from as-early-as 3-4 weeks of flowback data. The early evaluation of these wells will expedite critical completion and development decisions which will impact project economics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.