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These finds are mentioned since their discovery in situ with an overburden of volcanic pumice, dust and ash resting over the logs to a depth of 60 feet, points to the fact that the logs were covered by the explosive volcanic material so thickly and so fast that air was excluded and the hot material caused carbonization without combustion. The recent find of August 1 by Ranger-Naturalist Long establishes the fact that a similar action occurred on the outer slope of the old volcanic cone.

Conclusions

The location of a carbonized log within the existing crater slope, with a stump and roots uncarbonized and partially decomposed, presents many problems of great importance. It is quite evident that the attrition or wearing of the inner rim slope has shifted the crest of the rim outward and that at the time of entombment the tree was growing on the radiating slope of old Mt. Mazama. The tree was growing on a glaciated surface covered with glacial debris. Cool pumice and pumicite tumbled down the slope above to cover the roots and base of the tree, and then at a subsequent time hot volcanic ejecta, pumice, and ash settled around the tree so fast that air was excluded, combustion was prevented, and carbonization resulted. Subsequent glaciation ground down the sloping surface of the pumice, ash, and dust which had covered and carbonized the tree. The erosion at the rim slope has shifted outward so that now the specimen is located within the existing crest of the crater rim.

The wood of the roots and base of the tree trunk at the present time being only partially decomposed presents an implication that the explosive activity of Mt. Mazama was more recent than previously estimated. The presence of the upper glacial deposit establishes the fact that the entombment of this specimen was made prior to the destruction of the old volcanic cone since the higher elevations of the mountain necessarily existed in order to have a glacier form. The resulting distribution of glacial debris is one of the topmost coverings of the rim crest post-dates the final volcanic activity.

The similar conditions on entombment, carbonization of logs, and excessive depth of volcanic debris in the Diamond Lake Highway excavation postulates the tremendous amount of eruptive material distributed by explosive action of the volcano. It appears reasonable to assume that explosive action was the major force involved in the destruction of the upper portion of the volcanic cone, although it is possible subsidence, sapping, and undermining may have contributed an appreciable pat of the enlargement of the original crater.

Along the inner rim slope midway between Sinnott Memorial and Discovery Point occurs a record of three successive glaciations. There in the great outdoor laboratory of vulcanism and glaciation are found three separate layers of glacial drift. The accompanying diagram illustrates the arrangement of the several glacier evidences. A section by W. R. Atwood has been included as a means of comparing the evidence of glaciation found at different localities within the rim of the crater.

It will be readily seen that the record of glaciation found at “Glacier Point” is of much significance inasmuch as it represents two distinct outpourings of lava after the appearance of the first glacier. The question may be raised; Are the glacial tracks really the marks made by moving masses of ice or are they pseudo-glacial markings formed by the solidification of hot, seething masses of lava pouring out of a volcanic crater and down the mountain side?

Glacial striae are superficial scratches or grooves made on a rock surface by the tools of a glacier as it slides over the bedrock. These markings are usually arranged in parallel groups. The direction in which the striae are running is indicative of the general trend of movement of the glacier at that particular place. It happens that the rock surfaces will be somewhat polished and at least smoothed by the abrasive action of the ice and detritional rock fragments.

Banding due to flowage of the lava is the internal arrangement of particles within the lava flow. These particles may occur singly or in combination.

They may be crystals that had started to form before the ejection or outpouring of the lava from its conduit. They may be included material that were picked up by the lava as it moved over loose fragments of other rocks; or they may happen to be certain portions of the lava flow rich in volatile constituents which on release may leave cavities in the solidified lava and produce the frequent occurrence of lines or layers of bubble marks in a lava. One portion of this structure may vary in its relation to its remainder. Furthermore, one set of flow banding need not agree in attitude with the other sets of flow banding in a single lava bed. More often it happens that one flow structure can be traced to a place in the lava flow where it intersects a second flow banding. Fracturing of the lava during its cooling may produce smooth curved surfaces, but these will never be straight and polished as produced by glacial scour.

One who walks along the path of Nature to Discovery Point shall have a wonderful opportunity to read the story recorded in the rocks and distinguish between these confusing structures. Along this trail one first meets with glacial striae on the upper surfaces of many lava flows. Next a pseudo-striation produced by both flow banding and fracturing of the hot molten mass will be noted. And further along the trail Mother Nature has placed these two confusing structures together. The glacial striae are seen to be at right angles to the flow banding of the lava, and again, within the same lava flow, the striae are seen parallel to the banding. Truly, it is here where Mother Nature has solved the problem and completed the lesson for the day.

Gently stroke a marmot on the back — he flattens out like a fur rug — but be sure he gets the idea before you start the petting — those sharp teeth might cause sad retrospection; influx of visitors well underway — boy, place those garbage cans more conspicuously; “strength in numbers” found fallacious in E. C. W. boys’ football game with 17 on one side, 10 on the other — referee outmoded: — O lady! Those flowers don’t like to leave their homes — naughty, naughty — mustn’t pick; rainbow spawning in the lake — two to three months later than in water of ordinary temperature; tiny bear cub shinnying up a man’s leg with Mamma Bear unpreturbed — generally that man would be flirting with disaster; digging through five feet of snow to erect ranger-naturalists’ tents at the lake rim — no requests received from them for ice boxes; rangers enthusiastically aid scientist in quest of fleas from wild animals — interpretation left to reader; boulder from rim wall catapults into beached rowboat — matches no longer needed for toothpicks; 21 foot layer of snow at foot of lake trail a 6-5 favorite to last the summer; motorist demanding his permit dollar back — evening climate termed too frigid; 73′ 3″ of snowfall covers a lot of sins during the winter – but they come to light again with the melting; no two sagebrusher parties ever want the fireplace in quite the same place; E. C. W. boys — from the mid-west evince tremendous interest in the same mountain and forest work methods and lore; meanderings such as this call forth the catty remark to a poor driver — “Drive it or park it.” Let’s park it!

One of the most interesting and at the same time the easiest trips in the Park is the walk to Discovery Point. Here one sees the Lake in an every changing setting. Time and all subsequent agencies has played a part in eroding the crater wall. It is just beyond this point that the discovery was made of the carbonized log within the inner slope of the crater rim. The story of the past and a prophecy of the future is here written as clearly as though in print.

Trees, no doubt, once firmly rooted in firm rocks and soil are now hanging on by roots on one side only. Others twisted, gnarled, and broken give evidence of the winter’s blast. Again a small sapling growing near the brink will, without doubt, never reach maturity.

Rock ledges cracked and broken are adding their bit to talus slope and large boulders hanging in the balance are ready to crash downward to destroy a tree that even dares to grow.

Truly a battle is being waged and all the forces of nature have taken sides.

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