From abstract: A comprehensive geologic and engineering investigation was undertaken at the site on Buckboard Mesa selected for the SULKY event, a nuclear cratering experiment, conducted in dry basalt.

Abstract: Gamma radiation detectors in three fixed ground stations and in a helicopter were used in an attempt to measure the total radioactivity as a function of time for the dust cloud produced by the Sulky event. Large plastic s cintillators, photomultiplier tubes, and crudely collimated lead shields were the basic components of the detectors. A constant- current, variable -voltage regulator circuit enabled the detectors to operate in very high as well as in low radiation fields. Because the Sulky event did not crater as expected, there was no large radioactive dust cloud for the detectors to observe. Instead a small dust cloud of relatively low activity was produced, followed immediately by a continuous stream of much more radioactive gas which flowed from the resulting pile of rubble for a considerable length of time.