Nature Notes From Crater Lake
Volume 4, No. 2, August 1931
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. |
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. |
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
|