Spherical charges of cast TNT weighing 1000, 40,000, and 1,000,000 lb were detonated at various depths below the surface in desert alluvium soil and in basalt rock to determine variation in crater dimensions with burst depth and to define scaling laws relating the dimensions of large-charge craters with those of small-charge craters. Data suggest scaling as the 0.3 power of the charge weight, but consideration of gravity and overburden effects provide a variable scaling ranging from the cube root of charge weight for surface bursts or very small charges to the fourth root of charge weight for very large charges buried at relatively greater depths. Results show that, for these 2 media, dimensions agree if density alone is considered and strength properties are ignored. Close-in air blast is suppressed by charge burial to a greater extent than is air blast at greater distances. Ground-shock-induced air shock becomes more important relative to blast from venting gas as the burst depth is increased. Suppression of close-in air blast by charge burial is essentially the same for charges buried in basalt rock and alluvium soil. Empirical relations are derived showing the relation of the motion of the ground surface above the charge to the scaled burst depth.

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