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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

* * * * * *

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

Eohippus
There was once a little animal
No bigger than a fox,
And on five toes he scampered
Over Tertiary rocks.

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.

horse feet
Principal stages in the development of the forefoot of the horse.
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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26-Dec-2001