Hi 2 Cents. Jasper is also formed from sedimentary material so most likely the wood fell into the sediment and was covered very quickly so as to remove the oxygen, or kept it from being exposed to oxygen. The rest is history.

That is something I wish I knew more about. On our field trips we find all kinds of rocks, but we are never sure as to the nature of them. What Petra and I were mistaken about some rocks we found in her study area as being sedimentary in form turned out to be flow layering which was volcanic. Shouldn’t surprise us any as the whole area around where she lives is all volcanic. Wonder what it would take to get one to erupt again? I doubt that there is any chance of that in the very near future.

Speaking of volcanoes did you know that Medicine Lake volcano in Northeastern California is the largest active volcano in the Cascadia chain? There is a 7 x 12 kilometer depression in the summit area of the volcano.

During the past 11,000 years, eruptive activity at Medicine Lake volcano has been episodic. Eight eruptions produced about 5.3 cubic kilometers of basaltic lava during a time interval of a few hundred years about 10,500 years ago. That eruptive episode was followed by a quiet period that ended with a small andesitic eruption about 4,300 years ago. During the most recent eruptive episode between 3000 and 900 years ago, eight eruptions produced approximately 2.5 cubic kilometers of lava ranging in composition from basalt to rhyolite. Late Holocene lava compositions include basalt and andesite, however silicic lavas appear to be the dominant material that is erupted.

I deer hunted that area many years ago (late 50s and in the mid 80s) and never realized that it was a volcano. I thought the stuff I was finding all over the area came from Mt. Shasta. Take Care…Don in creepy town