Near-Surface Measurements of Deep Explosions I. Pressure Pulses from Small Charges

Abstract

The characteristics of pressure pulses recorded near the surface directly above small explosions at great depths are summarized. Charge weights ranged from 0.04 to 10 lb and burst depths varied from 3000 to 22 000 ft. Significant pressure and time parameters of the initial shock wave, the subsequent negative-pressure phase, and the first bubble pulse are shown in graphs and Tables. The vertical measurements of shock-wave peak pressure can be represented by the same power function that Arons previously determined from horizontal measurements of shallow explosions. These data extend the range of measurement for this parameter over an additional logarithmic cycle of the similitude curve to a distance R (ft) of 4×104 W12, where W is charge weight in pounds. The first period of the bubble oscillation also continues to show the same weight and depth dependence previously reported for depths ⩽500 ft down to depths of 22 000 ft.