Land subsurface detonation

The following discussion gives an example of the data treatment required to characterize the population for three cases—a land surface burst, a land subsurface detonation, and an airburst detonation. These three examples cover the complete range of types of solutions to the characterization problem. 

Figure 4. Land subsurface detonation. Aerial filter samples.

Table V. Fission Product Distribution Parameters (Land Subsurface Detonation)...

Detonations which produce particle populations of the first category are land surface bursts, land subsurface bursts, vented underground bursts, and tower bursts. 

As in the case of the land surface burst, complete characterization of the particle population requires only that particle mass, a volatile species, and a refractory species distribution with particle size be determined. All other isotopic distributions may be deduced from the istotope partition calculations described above. In the subsurface detonation, the earliest aerial cloud sample was obtained in the cloud 15 minutes after detonation. The early sample was, therefore, completely representative of the aerial cloud particle population. In Figure 5 the results of the size analysis on a weight basis are shown. Included for comparison is a size distribution for the early, local fallout material. The local fallout population and the aerial cloud population are separated completely from the time of their formation. 

C. Subsurface Burst. A subsurface burst weapon is detonated beneath the surface of land or water. Cratering will generally result from an underground burst, just as for a surface burst. If the burst does not penetrate the surface, the only other hazard will be from ground or water shock. If the burst is shallow enough to penetrate the surface, blast, thermal, and initial nuclear radiation effects will be present, but will be less than for a surface burst of comparable yield. Local fallout will be very heavy if penetration occurs. 

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