The video shows blasting of an underground tunnel. The initiation of the blast started in the center of the tunnel where the cut was placed and then expanded outwardly toward the peremiter holes and the lifter holes.
The cut is where the blast is initiated and creates the initial void of the blast which allows the blast to expand outwardly until the tunnel is fully excavated.
Please share your thought on the timing of this blast based looking at the initiation of the blast.
Video: MDC – The Metropolitan District