DEPARTMENT OF INTERIOR
NATIONAL PARK SERVICE
CRATER LAKE NATIONAL PARK
OREGON
Mr. E. C. Solinsky
Superintendent |
Mr. D. S. Libbey
Park Naturalist |
August, 1931 |
Vol. IV, No. 2 |
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This is one of a series of bulletins issued monthly during the
summer season, by the staff of the Educational Division to give
information on subjects of interest concerning the Natural History of
Crater Lake. It is supplemental to the lectures and field trips
conducted by the staff.
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Another Page From The Past Discovered
By D. S. Libbey
"Nature! We are surrounded and embraced by her; powerless to
separate ourselves from her, powerless to penetrate beyond her."
"She is ever shaping new forms, what is, has ever been; what has
been, comes not again. Everything is new, and yet naught but the old."
----- Goethe -----
In last month's Nature Notes mention was made of the numerous
discoveries of carbonized wood or natural charcoal which have been made
in the vicinity of the Rogue River where the Diamond Lake Road leaves
the main highway. The writer has been back to the place of the fossil
finds several times in an effort to secure a complete cross-section and
after many futile efforts finally succeeded in securing a cross-section
28 inches in diameter, on Thursday, July 23.
Mr. Harshbarger, of the Clarence Young Construction Company, which
is doing the excavating through the volcanic tuff and pumice on the
Diamond Lake Road, called us to come down the side of the mountain some
twenty miles and investigate the nature of the huge carbonized log which
was found approximately 1850 feet above the place where the new road
joins the Medford Highway. The log was covered by 55 feet of volcanic
ash and pumice which has become thoroughly consolidated and the specimen
was in a prostate position but with several lateral branches attached.
The under side of the log still carried the thick layers of bark resting
against very fresh appearing volcanic ash of a light gray color. The
portion of the bark which was on the under side was in a remarkable
state of preservation, uncarbonized, and the bark marking were very
evident. The bark shows the characteristics of the Sugar Pine bark
(Pinus lambertiana, Dougl.) and the carbonized log has numerous
portions showing the vesicular structure (bubbles and globules) caused
by the baking of the pitch in the log. Apparently the log was one which
had just fallen prior to its entombment and the fact that carbonized
branches were discovered seems to substantiate this opinion.
This find, in-situ, is considered a great value and the
cross-section has been placed in the Sinnott Memorial Building where it
will finally be assigned a very conspicuous place. The fossil section
is now held intact by a girdle of pine boards securely bound by wire so
as to make a retaining support. Very probably the section will
subsequently be either bound together by a series of brass straps or
incased in a matrix of plaster of paris because the terrific heat to
which the log was subjected caused rather large crevices to form and the
entire mass is very friable. This index from the past has the honor of
being the first display exhibit to be placed in the now Memorial
Building which was just dedicated on Thursday, July 16.
A week previous we had the pleasure of discovering another fossil
log approximately 8509 feet down from the Medford Highway junction on
the same construction project. One end of the log had been turned to
charcoal, the other being of uncarbonized wood. The end of the
preserved wood was covered by small pumice gravels and ash fragments
which apparently had tumbled down an ash and pumice slope and the very
definite bedding showed that the gravels were resting at the definite
angle of repose for such material and it is apparent that the covering
ash and pumice for the uncarbonized had come to rest and had tumbled
down the slope while cold. Also the log possessed no limbs and
indicated that it had floated to its place and then been buried under
the cold pyroclastic material. Very probably the entire log may have
been covered and then subsequent stream erosion had uncovered the lower
end of it, that is the end nearer to the present course of the Rogue.
Very definite stream laid depositions of gravel and sand were discovered
both above and below the site of the specimen. A part of the
uncarbonized wood has been obtained and will be placed in the Sinnott
Memorial building along with the large cross-section of the carbonized
log. The sequence of events seems to be that after the work of water
had sorted the pumice load, a huge deposit of volcanic ash and pumice
was spread over the material while the volcanic ejecta was still hot and
hence the carbonizing of the down stream, and, incidentally, the
westerly end of the log. It is unfortunate that the steam shovel had
destroyed all possibility of obtaining a cross-section of the log which
would have shown the joining of the carbonized with the non-carbonized
portion of the log. The overburden was about thirty feet thick.
It is apparent that the vast volcanic explosion which hurled the
nearly incalculable mass of ash and pumice occurred recently, that is
speaking in terms of geological time. The nearest orifice from which
such explosive material might have come appears to be the caldera of old
Mount Mazama.
My Kingdom For A Horse
By D. S. Libbey, Park Naturalist
There was once a little animal
No bigger than a fox,
And on five toes he scampered
Over Tertiary rocks.
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It has often been said that from the point of view of the geologist
there is little distinction between the Great Ice Age and the Recent
Epoch, the Age of Man. The former ended in the United States
when the last continental glacier in its northward retreat, about 35,000
years ago, abandoned the United States. When we can gather more
evidences of carbonized vegetation, possibly further search may reveal
specimens beneath the contacts of the dacite flow of Llao Rock and the
glaciated base on which it rests, we shall be able to tell with greater
accuracy the approximate age of the entombment.
It is quite evident that the destruction of Mount Mazama occurred
quite recently, speaking in geological terms, and the sculpturing
process is still actively being carried on. From year to year hug
spawls of rock tumble into the lake. One day last week a rock slide
occurred along the face of Cloud Cap and the dust continued to rise
along the talus slope for nearly two hours. This season a huge fragment
broke from the extreme west end of the Phantom Ship, thereby making more
slender one of the spars of The Ship.
It is apparent that the several carbonized logs are but preservation
of pre-existing life and consequently can be called fossils. Fossils
are they symbols in which the history of the world's life is written, an
a knowledge of the symbols is necessary before the story can be read.
Animals and plants that lived long ago were buried in mud in sedimentary
regions or in ash in volcanic regions just as those of today are being
so buried in some places. The mud hardened to rock or the ash became
indurated and then subsequent layers have been worn away as the mountain
has been eroded by the action of wind, water and ice, and there is good
probability that subsequent discovery will reveal the remains of animal
or plants which were entombed in Tertiary or Pleistocene time. May we
have additional discoveries. Who knew, but there is buried in the
volcanic ash and pumice the bones of a Tertiary horse? It certainly
would be a great pleasure to find the bones turned to stone of say the
four-toed horses (Eohippus) or the early three-toed horses
(Mesohippus) or the later three-toed horses (Merychippus)
or the one-toed (Equus). If any of the above should happen to be
found we would have the fossil index to the Eocene, Oligocene or Miocene
epochs of the Tertiary Period of geological time and to the Pleistocene
and Recent epochs -- in case the find should happen to be a one-toed
horse.
There have been fossil bones of the early horse discovered to the
north and east of this region. Of course it is very doubtful if we ever
will find the bones of such previous life in the vicinity of Crater Lake
since it is apparent that the heat was so great and very probably
organic material would have been consumed by the excessive heat.
Principal stages in the development of the forefoot of the horse.
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1 - Four-toed horse (Eohippus) - Eocene Epoch
2 - Early three-toed horse (Mesohippus) - Oligocene Epoch
3 - Later three-toed horse (Merychippus) - Miocene Epoch
4 - One-toed horse (Equus) - Pleistocene and Recent Epochs
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