Shoe width = 12 cm (got the number from my own shoes) = 12 px
width of the slash = 3 px = 3 cm
From the 3rd image
Tallest figure = 9 px = 1.9 m ( many people from the series are this tall)
Red line (width) = 88 px = 18.5 m
Red line (height) = 81 px = 17.1 m
Green line = 49 px = 10.3 m
The destroyed volume are 2 Rectangular parallelepipeds
V1 = 18.5 * 17.1 * 0.03 = 9.49 m^3
V2 = 17.1 * 10.3 * 0.03 = 5.28 m^3
Volume = V1 + V2 = 14.8 m^3
I assume that the rock was pulverized
E = 214 J/ccTotal Energy = 3167200000 Joules (756 kg of TNT) Building level