Blast Mtg Notes, 29 Dec 51

the advantages of earth cover on instrument shelters ond to permit better
estimates of damaye which a super bomb might do to deep underground installntions. Sandia had included the proposal primarily because the effects
people wanted it.
Data exist from Greenhouse studies on two buried Novy structures.
These seem to indicate no appreciable attenuation by the soil, rather a

general smoothing out cof the blast wave, so that it looks as though side-on
pressure had been applied rather than direct reflected pressure. The object
of this measurement would, then, be tc verify or disprove these findings,

and it ia felt that this could better be done in Nevada, where the soil is
more nearly like that of the rest of the country.
It might be added that
some measurements of this type were done in Nevada; the results had anomalies
such that the measurement should be repeated there.
It was alsc questioned whether holes shculd be dug in the coral
and the pressure attenuations measured at “ 50 ft. This would be below the
water table, and Cox doubted that one could expect any significant differences here from the measurements made with underwater gauges in the lagoon.
If anything of this type were done, it is felt it should be in the very high
over-pressure regions, since presumably a super bomb would only be used
against underground installations where the damage from a smaller bomb would

not be sufficient. This was discussed in some detail. It was finally concluded that techniques should first be investigated in Nevada. Again, the
situation at Ivy will have no relationship to the tactical ftring of a super.
AFSWP should be informed that we will make no measurerents of

this nature on Ivy.
G.

Long-Range Seismic Studies

Cox raised the question as to whether AFOAT would make these studies
on Ivy. So far, no one has been able to get their reports from previous
operations.
The shake that Bikini or Kwajalein would get is not of military
significance, but Cox thinks it offers valuable seismic data. He would expect
to give the information to a good, Qcleared seismologist and let him work
it over.
Before establishing seismic stations on outlying islands, he thought
we should find out where the existing stations are and then do only what is
necessary to augment the intermediate distances which are not covered. There
is one point, however:

the seismic stations around Boulder City are about

the most complete that Cox knows of, but during Buster-Jangle he found that
they have no way of measuring amplitudes, accelerations, velocities, and

the like--all they could say was that a signal arrived and whether it was
large or small.

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