A DEATH TRAP
by
F. R. Oberhansley, Junior Naturalist
One mile below the highway between Mammoth and Tower Falls on Geode
Creek are a series of interesting bogs. Situated in the bed of an old
glacial lake that has been filled with silt and encroaching vegetation
is a typical quaking bog. As one walks across this smooth grassy
surface, he is impressed with the fact that underneath the thin veneer
of grassy sod there is an unknown depth of jolly-like muck. The raft of
turf quivers and ripples for a distance of several yards at every
stop.
Near the western end of this grassy meadow are several breaks in the
turf where springs of clear water issue from below and fellow an
irregular channel to the outlet of the old lake. Nearby are the
carcasses of four elk cows and one cow moose (Alces americanus shirasi).
Evidence at hand proved that the elk had stepped into this innocent
looking stream-bed where they became hopelessly ensnared in the ooze and
were later dragged from the mire and devoured by grizzlies.
Tossing an old bone into one of the springs, I was impressed as it
slowly settled through the eighteen inches of crystal clear water to the
bottom, that its downward speed was not checked as it settled from sight
in this false bottom. A twelve foot stick was not sufficiently long to
plumb the depths at this point.
It is interesting to speculate how many skeletons may be resting on
the bottom of these death traps which must exact their annual toll from
our wilderness friends who would drink there. At times the entire
surface of a spring will be covered with a thick scum of hair.
In view of the present, our interpretation of conditions of the past,
as revealed by certain fossil animals, becomes more fascinating and
revealing.
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ACTIVITY OF GIANTESS GEYSER
by
Ranger Naturalist George Marler
The Giantess probably began erupting about three or four a.m. I first
noted the activity on May 30, 1938, at 7:30 a.m. At this hour I saw
several jets which seemed to rocket easily 200 feet. A number of
similarly high eruptions were noted throughout the day. After making
several inquiries and hearing numerous comments, I decided the eruption
must have begun about 3:30 and not later than 4:00 a.m.
During the course of the day the Giantess erupted periodically with
intervals varying between twenty and thirty minutes. The average
duration of each eruption, which was characterized by rocketing jets of
water, was about five minutes. Activity was just as strong at 8:00 p.m.
as during the morning hours.
At seven-thirty the following morning, there was still a churning of
water in the bottom of the crater. At no time during the day was any
water observed to be thrown above the rim. By 1:00 p.m. all boiling
seemed to have ceased. By 6:00 p.m. water could be seen standing at a
level near the bottom of the crater. At 7:30 a.m., June 1, the bowl was
about two-thirds full and the periodical ebulition that characterizes
the quiescent periods of the Giantess was noted. The bowl continued to
fill at the rate of about eight inches an hour, beginning to overflow
some time during the night of June 1. The Vault and Teakettle filled
simultaneously.
At the time of the first observation of the Giantess, May 30, the
water had receded two feet below the rim of the Butterfly and was
boiling vigorously. This boiling continued without abatement for a
period of not less than 48 hours. On the morning of June 2, the bowl was
overflowing, the water being several degrees below normal in
temperature.
The whitewashed appearance of the Giantess cone following the
activity was only in a small measure the result of the algae having been
destroyed by the boiling water. During the initial activity a large
quantity of finely suspended or held silica was ejected. Whether the
water had reached the saturation point for silica preceding the eruption
with a resulting precipitation would be interesting to ascertain. In
numerous collecting basins near the cone, this highly dissipated mineral
had collected, giving the appearance of marl or a foraminiferal
ooze.