Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Wellbore cement fracture permeability as a function of confining stress and pore pressure

Journal Article · · Geomechanics for Energy and the Environment
 [1];  [1];  [2];  [2];  [1];  [1]
  1. University of New Mexico, Albuquerque, NM (United States)
  2. Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

Cemented annulus fractures are a major leakage path in a wellbore system, and their permeability plays an important role in the behavior of fluid flow through a leaky wellbore. The permeability of these fractures is affected by changing conditions including the external stresses acting on the fracture and the fluid pressure within the fracture. Laboratory gas flow experiments were conducted in a triaxial cell to evaluate the permeability of a wellbore cement fracture under a wide range of confining stress and pore pressure conditions. For the first time, an effective stress law that considers the simultaneous effect of confining stress and pore pressure was defined for the wellbore cement fracture permeability. Here the results showed that the effective stress coefficient (λ) for permeability increased linearly with the Terzaghi effective stress ( -p) with an average of λ = 1 in the range of applied pressures. The relationship between the effective stress and fracture permeability was examined using two physical-based models widely used for rock fractures. The results from the experimental work were incorporated into numerical simulations to estimate the impact of effective stress on the interpreted hydraulic aperture and leakage behavior through a fractured annular cement. Accounting for effective stress-dependent permeability through the wellbore length significantly increased the leakage rate at the wellhead compared with the assumption of a constant cemented annulus permeability.

Research Organization:
Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
NA0003525
OSTI ID:
2311764
Alternate ID(s):
OSTI ID: 2000605
Report Number(s):
SAND--2023-03225J
Journal Information:
Geomechanics for Energy and the Environment, Journal Name: Geomechanics for Energy and the Environment Journal Issue: March Vol. 33; ISSN 2352-3808
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

References (49)

Nonlinear effective pressure law for permeability: Non-linear effective pressure law journal January 2014
Numerical investigation of methane and formation fluid leakage along the casing of a decommissioned shale gas well journal June 2015
Effect of pore and confining pressure on the supercritical CO2 permeability of sandstone: Implications for the effective pressure law journal August 2017
Methane Leakage From Hydrocarbon Wellbores into Overlying Groundwater: Numerical Investigation of the Multiphase Flow Processes Governing Migration journal April 2018
Comparison of the effective pressure law for permeability and resistivity formation factor in Chelmsford granite journal January 1988
Physical Modelling of Stress-dependent Permeability in Fractured Rocks journal April 2012
The role of hydromechanical coupling in fractured rock engineering journal January 2003
The effective pressure law for permeability of clay-rich sandstones journal May 2011
Variation of whole and fractured porous rock permeability with confining pressure journal October 1978
The permeability of whole and jointed Barre Granite journal August 1979
Effect of pore pressure and confining pressure on fracture permeability journal October 1981
Fundamentals of rock joint deformation journal December 1983
Water flow in a natural rock fracture as a function of stress and sample size journal August 1985
The effective pressure law for permeability in Chelmsford granite and Barre granite journal June 1986
Calculation of micro-annulus size in casing-cement sheath-formation system under continuous internal casing pressure change journal June 2015
The influence of confining stress and chemical alteration on conductive pathways within wellbore cement journal February 2009
Interface debonding as a controlling mechanism for loss of well integrity: Importance for CO2 injector wells journal January 2011
Dynamic alteration along a fractured cement/cement interface: Implications for long term leakage risk along a well with an annulus defect journal January 2011
Geomechanical Behavior of Wells in Geologic Sequestration journal January 2013
Towards a Frequency Distribution of Effective Permeabilities of Leaky Wellbores journal January 2013
Wellbore Permeability Estimates from Vertical Interference Testing of Existing Wells journal January 2013
Effect of CO 2 -induced reactions on the mechanical behaviour of fractured wellbore cement journal September 2016
Gas flow through cement-casing microannuli under varying stress conditions journal March 2018
A study on the hydraulic aperture of microannuli at the casing–cement interface using a large-scale laboratory setup journal March 2022
Temperature analysis for early detection and rate estimation of CO2 wellbore leakage journal December 2017
Effective stress law for the permeability of a limestone journal February 2009
Nonlinear flow behavior at low Reynolds numbers through rough-walled fractures subjected to normal compressive loading journal December 2015
Impact of groundwater flow on methane gas migration and retention in unconsolidated aquifers journal March 2020
Fluid flow regimes and nonlinear flow characteristics in deformable rock fractures journal January 2013
Oil and gas wells and their integrity: Implications for shale and unconventional resource exploitation journal September 2014
Improved model for gas migration velocity of stagnant non-Newtonian fluids in annulus journal September 2018
Characterization of wellbore casing corrosion product as a permeable porous medium journal September 2019
Surface Casing Pressure As an Indicator of Well Integrity Loss and Stray Gas Migration in the Wattenberg Field, Colorado journal March 2017
Characterization of the Mechanisms Controlling the Permeability Changes of Fractured Cements Flowed Through by CO 2 -Rich Brine journal September 2013
Permeability of Wilcox shale and its effective pressure law journal September 2001
Modeling Gas Migration, Sustained Casing Pressure, and Surface Casing Vent Flow in Onshore Oil and Gas Wells journal January 2019
Effective stress for transport properties of inhomogeneous porous rock journal January 1992
An exact effective stress law for elastic deformation of rock with fluids journal September 1971
Note on effective pressure journal May 1973
Validity of Cubic Law for fluid flow in a deformable rock fracture journal December 1980
Assessment and risk analysis of casing and cement impairment in oil and gas wells in Pennsylvania, 2000-2012 journal June 2014
The integrity of oil and gas wells journal July 2014
Crack Tunneling in Cement Sheath of Hydrocarbon Well journal October 2015
Well integrity: An overlooked source of risk and liability for underground natural gas storage. Lessons learned from incidents in the USA journal January 2009
Engineering Prediction of Axial Wellbore Shear Failure Caused by Reservoir Uplift and Subsidence journal February 2018
Determination of the Effective-Stress Law for Permeability and Deformation in Low-Permeability Rocks journal June 1992
A Laboratory Study of the Effects of Confining Pressure on Fracture Flow and Storage Capacity in Carbonate Rocks journal January 1975
Tightness Tests in Salt-Cavern Wells journal September 2001
Stress-Dependent Permeability of Fractures in Tight Reservoirs journal December 2018

Similar Records

Relative permeabilities for two-phase flow through wellbore cement fractures
Journal Article · Mon Jul 08 00:00:00 EDT 2024 · Geoenergy Science and Engineering · OSTI ID:2406570

Visco-inertial gas flow through wellbore cement fractures
Journal Article · Fri May 01 00:00:00 EDT 2020 · Journal of Natural Gas Science and Engineering · OSTI ID:1614781

Geochemical and Geomechanical Effects on Wellbore Cement Fractures
Journal Article · Tue Dec 30 23:00:00 EST 2014 · Energy Procedia · OSTI ID:1178504