A computer‐based system has been developed for the measurement of acoustic propagation loss in multipath arrivals of signals from explosive sources. The system involves both signal measurement operations and careful theoretical representations of the measured quantities. Initial applications have been for measurement of bottom‐reflection losses using signals which reflect many times from the bottom. It has been found that the levels of arrival pulses can be strongly affected by predictable surface‐reflection effects. Measurements demonstrate consistent bottom‐reflection loss values across homogeneous basin areas.