Radial and transverse strain seismometers using 6.1-m Invar rods were installed 457, 914, and 1524 m from ground zero on a nuclear detonation at the Nevada Test Site. The detonation, Hutch, took place in alluvium at a depth of 548 m and gave a body-wave magnitude of 5.4 ± 0.2. Dynamic and quasi-static strain data were recorded along with triaxial accelerations at the 914-m location.
The dynamic data show large strains (2 × 10-3 and considerable shear-wave activity related to the subsurface structure. Decay with range, corrected for the inelastic region, shows dependence of peak amplitudes of about R-3, but influence of the alluvium is present. The quasi-static data show large strain steps (> 10-4) at the two nearer stations and considerable dependence on alluvium depth. The strain decay with time is not consistent with that observed on Benham, and, at 914 m, appears to be a permanent step, similar to that observed on the Jorum event.