A large technological gap exists between the end of the fracturing process and the accumulation of long-term production data for the purpose of performing a meaningful analysis. Flowback analysis (FBA) has emerged as a successful technology to address this challenge without incurring incremental field costs and directly ties geomechanical properties of the rock to completion and well production. In the complete paper, a hybrid hydraulic fracture optimization and field development workflow is demonstrated that uses several recently introduced applications of FBA along with other commonly applied multidisciplinary analysis methods.
Theory and Methods
The authors propose a workflow designed to work alongside existing development processes. This novel approach seeks to rectify the shortcomings of static mapping and the data limitations of advanced numerical simulations and is developed to complement these workflows to form a comprehensive hybrid workflow for asset development. A diagram of the workflow is illustrated in Fig. 1 above.
The utility of the described workflow is multifaceted, but the authors aim to focus on the following three applications:
- The asset-development stage, or what the authors term an “asset-development playbook,” which serves as a strategic guide for project execution
- The evaluation of completion-design results, crucial for assessing the effectiveness of completion strategies
- The exploration of new areas, specifically stepping out to new areas or geological benches, vital for the expansion and exploration of potential resources
In the realm of data-driven analysis, the following four data sets, which comprise the foundational input data for the workflow, stand out for their common availability and utility in developing correlations:
- Drilling data
- 1D/3D geomechanics
- Diagnostic fracture injection tests
- FBA
These data sets not only are widely accessible but also can be expanded or enhanced with more-advanced data sets and interpretations to build or improve similar correlations. The authors emphasize the accessibility of advanced workflows to most operators without the need for additional field costs for data acquisition or specialized tools.
The analysis of these data sets yields two primary types of outputs: the spatial representation of reservoir and fluid properties, illustrated through maps, and the graphical representation of the relationship between effective stress and stimulated area as well as the pressure normalized rate vs. the FBA-derived linear flow parameter.
In a previous workflow in the literature, a key element is the development of physics-based correlations. One notable correlation highlighted is between effective stress and fracture area. This correlation is uniquely constructed on a per-fracture-area basis, illustrating the relationship between effective stress and the geometry generated by a given design.
The second key correlation explored in the study pertains to the 90-day pressure normalized rate and the linear flow parameter derived from FBA. This correlation establishes the link between the stimulation efforts required to sustain the target production levels of future wells.
Several key factors influence these correlations. One such factor is the fluid system, wherein significant variations may affect correlation results. To mitigate this issue, adjustments for gas content can be made or the asset can be segmented into areas with similar gas/oil ratios, allowing for the creation of distinct correlations for each segment.
Geomechanical properties also play a crucial role; substantial changes in these properties necessitate adjustments in the correlation. While the trend remains consistent, the actual value of the relationship between effective stress and stimulated area will vary according to the stress regime. As such, recalibrating the correlation is advised when encountering new geomechanical settings.
Finally, completion design is a critical factor during the correlation-development phase. For a more-accurate construction of the correlation, it is preferable to use a similar completion design, thus reducing discrepancies in the stimulated area caused by major changes in the size of stimulation or the fluid system used.
A case study included in the complete paper, to which much of the work is dedicated and in which the application of all three workflow stages is detailed, comes from a prolific North American volatile oil play and includes the analysis of nearly 150 production tests, which were collected primarily from public data sources. The application of the proposed workflow, and others of a complementary nature, is demonstrated with a focus on the practical value that the operator can realize by applying these methodologies while leveraging readily available data. The case study also demonstrates how operators can leverage publicly available data from their offsetting competitors to accelerate learning curves and avoid costly development challenges. Production test data is publicly available in many jurisdictions.
Results
In the detailed case study, the authors successfully introduced a physics-based workflow that capitalizes on data commonly collected during field development operations, thus eliminating the need for additional field expenses. This workflow is grounded in a comprehensive analysis of drilling data, geomechanical studies, petrophysical evaluations, and flowback data, each underpinned by actual independent field measurements. The strategic application of FBA, coupled with the development of physics-based correlations, effectively bridges a critical gap in the development workflow. This integration offers a nuanced understanding of how reservoir and geomechanical properties influence the effectiveness of well completions, the extent of stimulation required, and the anticipated production rates.
The implementation of this workflow yielded the following significant advancements:
- The creation of an asset-development playbook was a major milestone, synthesizing data on permeability and geomechanical properties with insights into the stimulated reservoir volume and the expected production performance. This playbook serves as a strategic guide for optimizing field development and enhancing production efficiency.
- An early-warning system was developed to proactively inform the development team about potential needs for optimization in upcoming well-completion designs.
- The optimization of the well-design process was achieved through an integrated modeling workflow that incorporates physics-based correlations, ensuring a more-accurate and -holistic understanding of well and reservoir behavior.
- The refined completion designs have significantly improved the performance of new drilling operations, elevating performance levels. This optimization reflects a deep understanding of subsurface conditions and operational dynamics, leading to more-productive and -cost-effective drilling outcomes.
- A decision-making and design-verification tool was developed that enables immediate evaluation of completion design changes post-pumping. This tool aids in rapid decision-making and ensures that design modifications are effective and aligned with overarching production objectives.
Discussion
The authors discuss only a limited scope of applications for the proposed workflow while not fully exploring how the asset-development playbook can be leveraged for improved budget planning and more-accurate type-curve assignment. A significant challenge addressed by the workflow is the pervasive issue of data scarcity that characterizes engineering projects, especially in the realm of unconventional development. Traditional approaches to reservoir mapping predominantly rely on data obtained from a handful of vertical pilot wells, often neglecting the rich data available from horizontal drills, a common feature in every unconventional play. The described workflow is designed to analyze the frequent flow tests conducted on horizontal wells, with the potential to augment data density by 25 to 50 times compared with what is achieved with vertical wells. This substantial increase in data availability creates a robust data set that serves as an excellent foundation for data-intensive methodologies, thereby enhancing the accuracy and effectiveness of analysis.
The development of the workflow is an ongoing process, with current efforts focused on deriving a correlation between the FBA-modified linear flow parameter and long-term production data. Through this work, patterns are observed that suggest well interference, which becomes more apparent in longer-term production data. The authors write that this observation guides them toward a more-systematic approach to quantifying the extent of interference and its relationship to well spacing. The issue of well interference has eluded a definitive solution, prompting continuous research and development efforts to devise a method that can reliably quantify well interference and optimize well spacing.
Conclusions
The authors demonstrate a physics-based workflow that uses typically gathered data to provide critical early-time insights into fracturing and well performance, well spacing, and overall field development planning and optimization.
The key benefits of these methods include the following:
- By analyzing flowback data and establishing physics-based correlations, the workflow offers insights into how reservoir and geomechanical properties relate to completion efficacy, stimulation requirements, and expected production.
- The timeline for analysis and evaluation is notably shortened.
- The developed workflow complements existing physics-based modeling workflows to form a powerful hybrid workflow that can greatly improve asset performance while minimizing the time and cost associated with analysis.
Key deliverables of the workflow include the following:
- The creation of an asset-development playbook aligns permeability and geomechanical characteristics with the stimulated area and expected production outcomes.
- The development of an early-warning system proactively mitigates underperforming wells and avoids lower-than-target-tier outcomes.
- Optimization and monitoring of completion -design performance is enabled within weeks of finishing pumping while using commonly gathered data with no additional field costs.
Download complete technical paper here. Available until 31 October 2025.
This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTeC 4043465, “A New Hybrid Workflow for Cost-Effective and Efficient Field Development Planning and Execution,” by Jesse D. Williams-Kovacs, SPE, and Dmitry Deryushkin, Subsurface Dynamics; and Brian Hepburn, SPE, Whitecap Resources, et al. The paper has not been peer reviewed.