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3225045 
Book/Book Chapter 
Hydraulic fracture containment: New insights into mapped geometry 
de Pater, HJ 
2015 
Society of Petroleum Engineers 
Richardson, TX 
2015 SPE Hydraulic Fracturing Technology Conference 
SPE-173359-MS 
English 
is a chapter of 3227282 2015 SPE hydraulic fracturing technology conference
Recently, fracture mapping has contributed a vast amount of data on hydraulic fracture geometry, but it is unclear what explains observed height containment. Re-analysis of published fracture mapping data yields a rule-of-thumb for expected fracture geometry and gives insight into the role of reservoir pressure in the observed containment. New developments in fracture propagation modeling provide a simple mechanism for stronger containment than predicted by conventional models.

Fracture containment is important for designing stimulation treatments that cover the entire pay, without breaching into aquifers or gas caps. Although modern fracture mapping provides the ground truth for post-treatment fracture geometry, it is still important to forecast fracture height growth based on pre-treatment data.

Fracture mapping shows that on average, fracture length is five times height. Some, (often depleted) reservoirs show even more extreme containment effects. In addition to stress differences, new mechanisms have been proposed to explain the strong observed containment, such as layer interface opening. Although such mechanisms are quite plausible in some formations, it is unlikely that they provide a universal explanation. A much simpler explanation comes from laboratory testing that indicated that fracture propagation must be described by a cohesive zone. In such a model, rock ruptures at the fracture tip due to effective stress exceeding strength. That introduces the difference between stress and pore pressure into fracture propagation, which can yield a strong containment effect.

The new insights in fracture containment can be used for guiding fracture design and for improving existing industry fracture models. 
9781613993705 
SPE Hydraulic Fracturing Technology Conference 
The Woodlands, TX 
February 3-5, 2015