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Call it a hunch, but was there once a large volcano around the Mt Daniel area that has since decomposed into the present massif?

The quick answer is that there was a volcano there, although I don't know how large it was. Cathedral Rock, which is due east of Mt. Daniel, is the remains of an ancient volcanic plug, so that entire subrange, consisting of Cathedral Rock, the Citadel, Mt. Daniel, and Mt. Hinman, are volcanic in nature. I don't think there was a huge mega-volcano like Mt. Rainier in the area, but it seems that this particular area had a volcano which went extinct and broke down into subpeaks much like the Goat Rocks Wilderness.

Yes. There was once a volcano at that location (I don't know if it was centered on Mt. Daniel). The volcanic rock type (silica-types) is indicative of a stratovolcano: andesite, rhyolite, dacite, and some other types I can't think of off-hand.

This site is instructive if a bit cumbersome:
http://home.comcast.net/~wa_geology/q304_frames.html
The Mt. Daniel environs are the red area at bottom right of the map (right of that white circle and by that lake, Pea Soup Lake?). Clicking on that red area, the Lithology box at the top changes to "dacite."

I had always wondered about Mount Daniel.

Fred Beckey called it volcanic, consisting of five separate summits :

(1) West Summit - 7960'

(2) Middle Summit - 7960'

(3) East Peak - 7899'

(4) West Pyramid - 7880'

(5) NW Peak - 7686'

Sweet! This nicely completes the last missing link in a pattern I noticed on Google Earth. Basically, from Mt Baker down to Lassen Peak, the major Cascade volcanoes are spaced at a fairly constant interval parallel to the Juan de Fuca subduction boundary. I theorized that the Mt Daniel area might have once had a volcano as it is located nicely on one of the spacing intervals.

The only real exception I've noticed is the close cluster of volcanoes stretching from Mt Jefferson to Mt Bachelor, but that stretch just so happens to be pretty close to the length of separation between the major volcanoes!

Does anyone have any thoughts on this phenomenon?

So far I just checked roughly on Google Earth, but now I think I may get a bit more exact to see how regular the volcano spacing is . . .

The present slow rate of convergence (3-4 centimeters per year) of the Juan de Fuca Plate is only about half its value at 7 million years, which probably explains the reduced seismisicity, lack of a trench, and debatable decline in volcanic activity.

When Mount Rainier was born (844,000 years ago), the Cascade volcanoes extending down
to northern California seemed to be much more active, hence the "extension" near The Three
Sisters area in present-day Oregon.

Mount Mazama was one of the major volcanoes of the High Cascades and is the largest edifice between Mount Shasta and the Three Sisters volcanoes. It's lavas have been dated
as young as 400,000 years old!

"Fire Mountains of the West" talks about the cascade volcano spacing, I dont recall offhand whether it mentions Mount Daniel or not though.

Thanks! That book looks like a great read.

So, why is Mt. Daniel not considered a "Cascade Volcano"? If Baker and Glacier Peak are within what most people refer to as the North Cascades, why not Daniel? This has always bugged me since it does fill in that "gap" in the chain of volcanoes.

Mount Hinman is "plutonic," meaning a body of intrusive igneous rock (called plutonic rock) CRYSTALLIZED from magma slowly cooling below the surface of the Earth.

Speculating that Daniel has formed a PLUTONIC relationship with Mount Hinman over the years, thus excluding them BOTH from TRUE"volcanic" status.

Actually, only this man KNOWS for sure ...

[youtube]http://www.youtube.com/watch?v=N9qYF9DZPdw[/youtube]