a factor of 1.5 fo saturated soil.
It is felt, however, that for media other than sand,
such as coral or vock, the degree of saturation is lower and a smaller factor should be
used. In the cas. of Lacrosse, a factor of 1.3 to 1.4 may be more applicable.
The adjusted crater depth is more a matter of conjecture, but it is felt that the under-
lying formations, acting as interfaces, decreased the depth considerably.
The relative
flatness of the ci :ter bottom tends to support this theory. It is believed that the crater
depth would have about the same soil factor as the crater radius had no interfaces been
present. A deptl. factor of 1.5 is given in TM 23-200 for saturated sand.
One shot is not considered sufficient evidence from which to obtain a soil factor, and
one obtained frori data such as given above is based at the best on a large amount of
guesswork.
4.3
SHOT ZUNI
It is felt that the Zuni results should be viewed rather critically before being included
in the weapon-ef ‘ect literature because of the unusual burst situation. Ground zero for
this burst was le 3s than 100 feet from the edge of the water-filled Morgenstern crater.
This may have a fected the resulting crater. Since so much of the area encompassed by
subsurface shoch was underwater, the shock was transmitted through water for a considerable distance before entering the earth. It could be expected that water would not
attenuate the shock as much as soil, thereby giving an abnormal effect on that side of
ground zero. Hc wever, the shock strength could have been changed by reflection at the
water-soil interfice.
The size of the crater is smaller than expected, both in radius and
depth, and because of the many difficulties in explaining conditions surrounding the burst,
itis not felt that this difference from the average EPG results should be considered serious.
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