**7. Conclusions**

The new approach developed to account for the complex processes due to NF permeability accompanying HF/NF interaction have been presented in detail. This approach accounts for the important physical processes taking place during HF and permeable NF interaction, and will be implemented in UFM.

The next step is to evaluate the influence of leakoff into the natural fractures during HFN simulations on the total HFN footprint and production forecast. The approach will be also validated against existing numerical, experimental and field data.

### **Author details**

Olga Kresse and Xiaowei Weng

\*Address all correspondence to: okresse@slb.com

Schlumberger, Sugar Land, USA

### **References**

[1] Kresse, O, Cohen, C. E, Weng, X, Wu, R, & Gu, H. Numerical modeling of hydraulic fracturing in naturally fractured formations. 45th US Rock Mechanics/ Geomechanics Symposium, San Francisco, CA, June, (2011). , 26-29.

[2] Chuprakov, D, Melchaeva, O, & Prioul, R. Hydraulic Fracture Propagation Across a Weak Discontinuity Controlled by Fluid Injection. InTech; (2013).

**•** Calculate the flow rate and volume of fluid injected to NFs at each pressure iteration, and update/calculate pressure along HFN using existing scheme for opened elements and new equations (described above) for elements in closed invaded and pressurized NF parts

**•** From the calculated pressure in NF elements iteratively update the positions of the propa‐ gating fronts for opened, filtration, and pressurized zones in NF during pressure/time step

**•** Include the elements in the closed parts of invaded NFs into the stress shadow calculation

The fully coupled NF modeling approach is heavier and more CPU expensive than decoupled approach. The Decoupled Numerical Approach has been selected as basic approach and it is

The new approach developed to account for the complex processes due to NF permeability accompanying HF/NF interaction have been presented in detail. This approach accounts for the important physical processes taking place during HF and permeable NF interaction, and

The next step is to evaluate the influence of leakoff into the natural fractures during HFN simulations on the total HFN footprint and production forecast. The approach will be also

[1] Kresse, O, Cohen, C. E, Weng, X, Wu, R, & Gu, H. Numerical modeling of hydraulic fracturing in naturally fractured formations. 45th US Rock Mechanics/ Geomechanics

**•** Track the pressure at intersections to capture when NF start to open

described schematically on Figure 5 as a part of total solution

validated against existing numerical, experimental and field data.

Symposium, San Francisco, CA, June, (2011). , 26-29.

iterations

306 Effective and Sustainable Hydraulic Fracturing

scheme

**7. Conclusions**

**Author details**

**References**

will be implemented in UFM.

Olga Kresse and Xiaowei Weng

Schlumberger, Sugar Land, USA

\*Address all correspondence to: okresse@slb.com


[14] Blanton, T. L. An Experimental Study of Interaction Between Hydraulically Induced and Pre-existing Fractures. SPE 10847, Presented at the SPE/DOE Unconventional Gas Recovery Symposium, Pittsburgh, PA, May (1982). , 16-18.

[28] Meyer, B. R, & Bazan, L. A Discrete Fracture Network Model for Hydraulically In‐ duced Fractures: Theory, Parametric and Case Studies, SPE 140514. Presented at the SPE Hydraulic Fracturing Tech Conference and Exhibition in The Woodlands, Texas,

Hydraulic Fracturing in Formations with Permeable Natural Fractures

http://dx.doi.org/10.5772/56446

309

[29] Rogers, S, Elmo, D, Dunphy, R, & Bearinger, D. Understanding Hydraulic fracture geometry and interactions in the Horn River Basin through DFN and Numerical modeling, SPE 137488, 2010. Presented at the Canadian Unconventional Resources & International Petroleum Conference, Calgary, Alberta, Canada, October, (2010). ,

[30] Nagel, N, Damjanac, B, Garcia, X, & Sanchez-nagel, M. Discrete Element Hydraulic Fracture Modeling- Evaluating Changes in natural Fracture Aperture and Transmis‐ sivity, SPE 148957, 2011. Presented at the Canadian Resources Conference, Calgary,

[31] Fu, P, Johnson, S. M, & Carrigan, C. R. Simulating Complex Fracture Systems in Geo‐ thermal Reservoirs Using an Explicitly Coupled Hydro-Geomechanical model, AR‐ MA Presented at 45th US Rock Mechanics/Geomechanics Symposium, Salt Lake City,

[32] Dershowitz, W. S, Cottrell, M. G, Lim, D. H, & Doe, T. W. A Discrete Fracture Net‐ work Approach for Evaluation of Hydraulic Fracture Stimulation of Naturally Frac‐ tured Reservoirs, ARMA-475, 2010. Presented at 44th US Rock Mechanics

[33] Rahman, M. M, Aghigi, A, & Sheik, A. R. Numerical Modeling of Fully Coupled Hy‐ draulic Fracture propagation in Naturally Fractured Poro-Elastic Reservoirs", SPE 121903, 2009. Presented at the 2009 SPE EUROPEC/EAGE Conference, Amsterdam,

[34] Brown, S. R, & Bruhn, R. L. Fluid permeability of deformable fracture network. Jour‐

[35] Cooke, M. L, & Underwood, C. A. Fracture termination and step-over at bedding in‐ terfaces due to frictional slip and interface opening. Journal Structural Geology,

[36] Hossain, M. M, Rahman, M. K, & Rahman, S. S. Volumetric Growth and Hydraulic Conductivity of naturally fractured reservoirs during hydraulic fracturing: A case study using Australian Conditions, SPE 63173, 2000. Presented at the 2000 SPE Tech‐

[37] Chuprakov, D. A, Akulich, A. V, Siebrits, E, & Thiercelin, M. Hydraulic-Fracture Propagation in a Naturally Fractured Reservoir.SPE 128715, 2011. Presented at the SPE Oil and Gas India Conference and Exhibition, Mumbai, India, January (2010). ,

nical Conference and Exhibition, Dallas, Texas, October (2000). , 1-4.

2426 January (2011).

Alberta, Canada, Novebmer (2011). , 15-17.

Symposium, San Francisco, CA, June (2010). , 26-29.

nal of Geophys. Research (1998). B2): 2489-2500.

UT, June 27-29, (2011). , 11-244.

The Netherlands, June (2009). , 8-11.

(2001). , 23, 223-238.

20-22.

19-21.


[28] Meyer, B. R, & Bazan, L. A Discrete Fracture Network Model for Hydraulically In‐ duced Fractures: Theory, Parametric and Case Studies, SPE 140514. Presented at the SPE Hydraulic Fracturing Tech Conference and Exhibition in The Woodlands, Texas, 2426 January (2011).

[14] Blanton, T. L. An Experimental Study of Interaction Between Hydraulically Induced and Pre-existing Fractures. SPE 10847, Presented at the SPE/DOE Unconventional

[15] Blanton, T. L. Propagation of Hydraulically and Dynamically Induced Fractures in Naturally Fractured Reservoirs. SPE Unconventional Gas Technology Symposium;

[16] Gu, H, & Weng, X. Criterion For Fractures Crossing Frictional Interfaces At Non-or‐ thogonal Angles. 44th US Rock Mechanics Symposium and 5th US-Canada Rock Me‐ chanics Symposium; 01/01/2010; Salt Lake City, Utah: American Rock Mechanics

[17] Gu, H, Weng, X, Lund, J. B, Mack, M, Ganguly, U, & Suarez-rivera, R. Hydraulic fracture crossing natural fracture at non-orthogonal angles, a criterion, its validation and applications. Paper SPE 139984 presented at the SPE Hydraulic Fracturing Con‐

[18] Kresse, O, Weng, X, Chuprakov, D, Prioul, R, & Cohen, C. E. Effect of Flow Rate and

[20] Nolte, K. G, & Smith, M. B. Interpretation of Fracturing Pressures SPE 8297, Septem‐

[21] Castillo, J. L. Modified Fracture Pressure decline Analysis Including Pressure-De‐

[22] Nolte, K. G. Fracturing Pressure Analysis for Non-Ideal Behavior. SPE 20704, JPT,

[23] Warpinski, N. R. Hydraulic Fracturing in Tight, Fissured Media. SPE 20154, JPT, Feb‐

[24] Barree, R. D, & Mukherjee, H. Determination of Pressure Dependent Leakoff and its effect on Fracture geometry, SPE 36424, 1996. Presented at the 71st Annual Tech Con‐

[25] Mukherjee, H, Larkin, S, & Kordziel, W. Extension of Fracture Pressure Decline Curve Analysis to Fissured Formations. SPE 21872, 1991. Presented at the Rocky Mountain Regional meeting and Low Permeability Reservoirs Symposium, Denver,

[26] Walsh, J. B. Effect of Pore Pressure and Confining Pressure on Fracture Permeability,

[27] Warpinski, N. R. Fluid leakoff in natural fissures. In: Economides&Nolte: Reservoir

In. J. Rock Mech. Min. Sci. & Geomech. Abstr. (1981). , 18, 429-435.

ference and Exhibition, Denver Co, October, (1996). , 6-9.

ference and Exhibition, Woodlands, Texas, January, (2011). , 24-26.

Viscosity on Complex Fracture Development in UFM. InTech; (2013).

[19] Economides, M. J, & Nolte, K. G. Reservoir Simulation. Third edition. (2000).

Gas Recovery Symposium, Pittsburgh, PA, May (1982). , 16-18.

01/01/1986; Louisville, Kentucky (1986).

Association; (2010).

308 Effective and Sustainable Hydraulic Fracturing

ber (1981).

February (1991).

Co, April (1991). , 15-17.

Stimulation, (2000).

ruary (1991).

pendent leakoff, SPE 16417, (1987).


[38] Tezuka, K, Tamagawa, T, & Watanabe, K. Numerical Simulation of Hydraulic Shear‐ ing in Fractures Reservoir. Proceeding World Geothermal Congress, Antalya, Tur‐ key, April (2005). , 24-25.

**Chapter 15**

**Injection Modeling and Shear Failure Predictions in Tight**

This work presents theory for modeling of fracture propagation within reservoir simulator, history matching of field injection pressure using uncoupled and fully coupled geomechanical injection models, and sensitivity study of various parameters such as permeability enhance‐ ment/reduction functions, limiting length of fracture propagation, stress factor, and Biot's constant. Two wells completed in tight gas sands in Western Canadian sedimentary basin were studied. The wells were fractured with different techniques (i.e., X-link gelled water fracs (Well A) and un-gelled slick water fracs (Well B)) and were both successfully matched with coupled

Fracture propagation modeling is an important part of reservoir geomechanics and must be considered in injection modeling of wells. Classical modeling of fracture geometry is well established and documented in literature of rock mechanics and stimulation [3]. Direct coupling of fracture propagation (fracture dynamics) and fluid flow is computationally very expensive [4, 5]. The modeling of "complex" fracturing [6] is also expensive. However, proper representation of dynamic propagation in which the fracture is directly coupled into a reservoir simulator is important for many applications. It has been shown that the some degree of coupled treatment of fracture mechanics, reservoir modeling and geomechanics is important for better understanding of the unconventional fracturing applications as well as for tight gas fracturing treatments such as waterfracs [7, 8]. While the fully coupled approach [5, 12] is not

and reproduction in any medium, provided the original work is properly cited.

© 2013 Islam and Settari; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

**Gas Sands — A Coupled Geomechanical Simulation**

**Approach**

**Abstract**

geomechanical model.

**1. Introduction**

Arshad Islam and Antonin Settari

http://dx.doi.org/10.5772/56312

Additional information is available at the end of the chapter

