**Author details**

(a) (b) (c)

586 Effective and Sustainable Hydraulic Fracturing

**Figure 10.** Reservoir temperature profile (top) and Log10RMS fluid velocity profile (bottom) after (a) 1 year (b) 10 years and (c) 14 years of production with σH = 78.9 MPa and σh = 53.3 MPa, Pinj=44.8 MPa and Pprod=31 MPa.

(a) (b) (c)

**Figure 11.** x (top) and y (bottom) component of effective stress after (a) 1 year (b) 10 years and (c) 14 years of produc‐

tion with σH = 78.9 MPa and σh = 53.3 MPa, Pinj=44.8 MPa and Pprod=31 MPa.

Nima Gholizadeh Doonechaly1 , Sheik S. Rahman1\* and Andrei Kotousov2

\*Address all correspondence to: sheik.rahman@unsw.edu.au

1 School of Petroleum Engineering, University of New South Wales, Sydney, Australia

2 School of Mechanical Engineering, the University of Adelaide, South Australia, Australia

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Fully Coupled Thermo-Poroelastic Numerical Approach. 36th Geothermal Resources Council Transactions, 2012.

**Chapter 28**

**Fracture Network Connectivity — A Key To Hydraulic**

F. Zhang, N. Nagel, B. Lee and M. Sanchez-Nagel

Additional information is available at the end of the chapter

corresponding stimulated volume, and well production.

http://dx.doi.org/10.5772/56302

**Abstract**

**1. Introduction**

**Fracturing Effectiveness and Microseismicity Generation**

In this work, the effect of fracture network connectivity on hydraulic fracturing effectiveness was investigated using a discrete element numerical model. The simulation results show that natural fracture density can significantly affect the hydraulic fracturing effectiveness, which was characterized by either the ratio of stimulated natural fracture area to hydraulic fracture area or the leakoff ratio. The sparse DFN cases showed a flat microseismic distribution zone with few events, while the dense DFN cases showed a complex microseismic map which indicated significant interaction between the hydraulic fracture and natural fractures. Further, it was found that the initial natural fracture aperture affected the hydraulic fracturing effec‐ tiveness more for the dense natural fracture case than for the sparse (less dense) case. Overall, this work shows that fracture network connectivity plays a critical role in hydraulic fracturing effectiveness, which, in-turn, affects treating pressures, the created microseismicity and

The extremely low permeability of the common shale plays means that simple, bi-planar hydraulic fractures (HF) do not create enough surface area to make economic wells and that stimulation of the natural fracture system is critical [1]. Numerous field microseismic data sets have shown that extreme fracture complexity may result from the interaction between a created hydraulic fracture and the pre-existing fracture network [2, 3]. Consequently, operators will often alter the stimulation design, by changing injection rate, viscosity, or other parame‐ ters, in order to improve the effectiveness of the stimulation in unconventional shale plays.

> © 2013 Zhang et al.; 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,

> © 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,

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

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

