In the past two issues of Nature Notes the Park Naturalist made reference to recent discoveries of carbonized wood in the vicinity of the Rogue River, west of the park. The logs which were found buried beneath layers of pumice were completely changed to charcoal. The discovery was of special significance for it aided the geologist in interpreting the history of Mount Mazama and Crater Lake.

This first discovery caused considerable excitement at the lake and the naturalists were anxious to locate similar deposits within the park boundaries. Their hopes were fulfilled on August 20, when during a geological investigation of Pumice Point a layer of soil was found buried deep beneath the loose pumice and containing numerous fragments of carbonized wood. This discovery inside of the rim of Crater Lake, directly across from the Sinnott Memorial, proved to be of still greater significance than the first one, for associated with the soil and pumice material was found evidence of repeated glaciation.

If we could picture the landscape in this region as it appeared some twenty or thirty thousand years ago we would see Mount Mazama a volcanic mountain covered with glaciers. It probably resembled Mount Hood and Mount Rainier as we know them today. The glaciers which occupied the valleys of this former mountain left the material marked "First Glacial Deposits" in the accompanying diagram. Suddenly, while glaciers still existed on the mountain, the volcano erupted and covered the glaciers with pumice and lava. This caused the ice to melt, but soon now glaciers grew and moved slowly down the slopes of Mount Mazama. This second group of glaciers left the material marked "Second Glacial Deposits" on the diagram. They also left glacial scratches or striae on the lava beneath. This time the glaciers were not immediately covered by pumice, but considerable time elapsed during which a layer of soil was formed and vegetation flourished on the slopes of the mountain. This is proven by the presence of carbonized plant remains in the soil layer indicated in the accompanying diagram. Again history repeated itself and Mazama erupted to cover this soil and vegetation with thick deposits of pumice. Glaciation occurred once again and possibly still a fourth time as is indicated by glacial material interbedded with the pumice and volcanic ash.

Thus, from the little section exhibited on Pumice Point, the geologist may read a portion of the story of Mount Mazama. The rocks are as leaves in a great book which records the history of our earth. Sometime perhaps we will locate all the pages of this geologic time table and be able to read more perfectly the romance of Mount Mazama and Crater Lake.