The present operative concept model for hydraulic fracturing (see Miskimins 2019) is shown to be physically impossible. The conceptualisation that underpins current practice is little changed from the time of its introduction by Hubbert and Willis (1957), and imagines a planar fracture opened within the rock mass by the injection of high-pressure fluid into the rock. Current practice typically uses very large volumes of water that exceed the void space created inside the notional fracture. The opening of the fracture causes new strains within the rocks that bound the fracture, with energy budget consequences. The excess water is often implied to go into pre-existing void spaces, also with energy consequences. Both of these explanations involve consequent energy changes that are more than an order of magnitude larger than the input energy amount, so they have to be impossible. Alternate process models, based on activation of natural fracture systems, require less energy, and so are deemed to be the likely reality
|Number of pages||10|
|Publication status||Accepted/In press - 26 May 2020|
|Event||US Rock Mechanics/Geomechanics 54th Symposium - Golden, United States|
Duration: 22 Jun 2020 → 25 Jun 2020
|Conference||US Rock Mechanics/Geomechanics 54th Symposium|
|Period||22/06/20 → 25/06/20|
Couples, G. D. (Accepted/In press). Where is the Water? – A Physics Analysis to Identify Possible Processes in Hydraulic Fracturing. Paper presented at US Rock Mechanics/Geomechanics 54th Symposium, Golden, United States.