Fracture Decoupling Experiment 2

Well-known hypothetical nuclear explosion evasion scenarios include cavity decoupling and placing nuclear tests within routine ripple-fired mine explosions. We consider a different scenario: using “repeat shots” - explosions conducted in the damage (fracture) zone created by an earlier explosion(s), which may considerably reduce the amplitudes of the subsequent explosions due to a fracture decoupling. We are going to conduct a unique experiment to quantify the effects of fractures on chemical explosion decoupling. We will conduct a series of four explosions (shots) ranging from 500 to 2000 lbs in order to extensively fracture granitic emplacement media. Seismic signals from the explosions will be recorded on temporary near-source and local stations as well as permanent stations. We will then re-drill the same blast holes, use borehole cameras to estimate fracture densities, and then reload the holes for a second series of equivalent yield shots.