Wow! Thank you. The math surprisingly simple, but I get the drift.
News to me: fractures are mostly vertical , I thought they were mostly horizontal. And the pressures -even at 20k lbs./psi - are far below what I thought were required.
Isn’t fracking done in granite too? What is the PR for granite?
Granite PR is probably around 0.2. not tolerating a lot of bend before it snaps.
there have been be instances of frac’ing granite, but not like in the simple planar fracturing sense. What would be the use? It’s very low porosity and can’t store much or any reservoir fluids. There are rare hydrocarbon deposits seeped out of sedimentary source rocks above or alongside granite. In order to store hydrocarbons, or water in geothermal heat operation, the granite must have a naturally fractured secondary porosity and permeability system in place. Granite formation frac jobs are really just injection to sweep reservoir damage from drilling out away from the wellbore. There may occur induced fracture components in the process, but likely not the main objective.