Stress insensitive natural fracture permeability within hydrocarbon reservoirs

Conventional models of natural fractures assume that fracture permeability is predominantly caused by the mismatch between rough surfaces, and is highly sensitive to any changes in the effective stress acting normal to the fracture plane. Thus on depletion, a naturally fractured reservoir should experience a dramatic decrease in permeability. Using examples of long term depletion from hydrocarbon reservoirs, the inferences drawn from the conventional model of fracture permeability are compared with actual behaviour. These findings, together with reservoir description are used to construct a new model of natural fracture permeability, ‘locked open natural fractures’ which fits observed field behaviour.

• 1.0 INTRODUCTION

• 2.0 NATURAL FRACTURE PERMEABILITY WITHIN HYDROCARBON RESERVOIRS

• 3.0 STRESS INSENSITIVE NATURAL FRACTURE PERMEABILITY

• 4.0 CONCLUSIONS

• ACKNOWLEDGEMENTS

• REFERENCES