Coupled Geomechanical Modeling to Assess Cap Rock Integrity and Mechanical Fault Stability: Application to Farnsworth Field Unit Project
- Marcia McMillan (New Mexico Tech, Petroleum Recovery Research Center) | Robert Will (Petroleum Recovery Research Center) | William Ampomah (Petroleum Recovery Research Center) | Robert Balch (Petroleum Recovery Research Center) | Paige Czoski (Petroleum Recovery Research Center)
- Document ID
- Society of Petroleum Engineers
- SPE Western Regional Meeting, 23-26 April, San Jose, California, USA
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- Geomechanical Modelling, Two Way Coupling, Farnsworth Field Unit, Fault Stability and Caprock Integrity, CO2 sequestration
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- 150 since 2007
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The SWP project is located in a mature waterflood undergoing conversion to CO2-WAG operations in the Farnsworth, Texas, USA. Anthropogenic CO2 is sourced from a fertilizer and an ethanol plant. This work utilizes Farnsworth’s full-field, history-matched, compositional hydrodynamic coupled geomechanical model for assessing the impact of stress changes observed through the history matched field life. Production and injection induced stress changes, fault stability and caprock integrity investigations are performed to project the potential for fault reactivation and the loss of caprock integrity under shear failure.
A static mechanical earth model (MEM) was constructed for use in transient coupled geomechanical model based on the existing Southwest Regional Partnership (SWP) geological model. The static MEM inherits the stratigraphic and structural features of the geologic model and incorporates additional overburden, underburden, and sideburden formations required to impose mechanical boundary conditions. Mechanical properties were distributed in the 3D MEM through integration of geophysical logs and 3-dimensional seismic elastic inversion properties using a combination of Bayesian and stochastic interpolation methods. These data are further enhanced by lab derived strength and failure criteria for the caprock interval. Additionally, interpreted faults and other geological features were included as part of the static structural framework to fully represent subsurface hydraulic and mechanical systems and appropriately integrate heterogeneity. Two-way coupling of hydrodynamic flow and geomechanical simulations incorporates the Kozeny-Carman relationship for updating permeability and is history matched through primary, secondary (waterflooding) and tertiary (CO2 WAG) recovery periods before performing a twenty year forecast.
Two-way simulations are performed to understand the effective stress perturbations imposed by field operations: water injection and the more recent implementation of WAG. Evaluation of Mohr circles with liquid production and field pressure charts as well as slip tendency and distance to failure metrics indicate that neither our faults or cap rock are critically stressed. This paper presents the results of the Farnsworth initial attempts to integrate the seismic driven 3D MEM into coupled hydrodynamic geomechanical history match simulation workflow.
|File Size||2 MB||Number of Pages||21|
Altaf, I., Towler, B., Underschultz, J., Hurter, S., & Johnson, R. (2018). A Review of Current Knowledge with Geomechanical Fault Reactivation Modelling: The Importance of CO2 Mechano-Chemical Effects for CO2 Sequestration. Paper presented at the SPE Asia Pacific Oil and Gas Conference and Exhibition, Brisbane, Australia. https://doi.org/10.2118/192024-MS
Ampomah, W., Balch, R. S., Grigg, R. B., Will, R., Dai, Z., & White, M. D. (2016). Farnsworth Field CO2-EOR Project: Performance Case History. Paper presented at the SPE Improved Oil Recovery Conference, Tulsa, Oklahoma, USA. https://doi.org/10.2118/179528-MS
Balch, R., & McPherson, B. (2016). Integrating Enhanced Oil Recovery and Carbon Capture and Storage Projects: A Case Study at Farnsworth Field, Texas. Paper presented at the SPE Western Regional Meeting, Anchorage, Alaska, USA. https://doi.org/10.2118/180408-MS
Lee, D. W., Singh, V., & Berard, T. (2009). Construction of a Mechanical Earth Model and Wellbore Stability Analysis for a CO2 Injection Well. Paper presented at the SP[ International Conference on CO2 Capture, Storage, and Utilization, San Diego, California, USA. https://doi.org/10.2118/126624-MS