The passage of a detonation wave through a [[Column Charge|column]] of high explosive travelling at the velocity characteristic of the explosive formulation. Propagation can also refer to the instantaneous initiation of adjacent explosive substances contained in boreholes that are too close together. Propagation can bypass the intended delay times for firing adjacent explosives loaded into boreholes drilled too close together, thus producing excessive vibration levels as well as poor fragmentation due to insufficient [[Burden|burden]] relief.