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typo corection: 'one' I really hate code! LOL ;-)

.........I believe one of the most important physical characteristics we see here is the molecular or crystal lattice apperant and particular to Basalt; is Columnar Jointing. A very important thing in this rock. The most famous of such as Devil's Tower, Devil's Postpile, Giants Causeway. The best examples perfect Hexagonals, and to lesser degrees more quadrant shapes. You can clearly see the vertical striations following cleavage and stress fracture lines. I always love the many methods evolved in western basalt stratas and am almost amazed we haven't built grand cities from the available building materials that are built by fire. One of my favorite areas is the Warm Springs Indian Reservation town, the layering of the basalt as you drive west on the highway through the resevation. Passing through layers of volcanic time, seeing so many examples of amazing igneous formations. I have always thought of the area as a basaltic indian fortress against the impending white enemies. It looks so impregnable and forbidding, yet amazing examples of basalt and ash , and pyroclastic flow; pratically a mile thick in areas from the great Mazama Eruption 65000 y.o. Common to most as Crater Lake and Discovery Island in the caldera of Mazama. Here you can imagine being a hot ember of pyroclastic flow hurtling into the air as majestic volcanics come to life.....

..........oops.!.6500 y.o.

Well, you certainly know your basaltic structures, Erik. I must say, I'm impressed. ;-)

Eric

Do we need more hints? One knows of Devil's tower and doesn't know what this thing is? Interesting.....

Like I said, I'm new at this. Am I understand that this is an ancient volcano? I have my textbooks and looked in there last night. I looks like Sailing Ship but you say it's not in that area....but am I to assume that it is the same type of structure?

suzieb,

This structure the the remains of an intrusive or extrusive igneous event. Tens and tens of millions of years ago. Yes, it does look like a "Shiprock."

............without being there to touch it, I only think I am seeing as Eric suggested, some type of basaltic volcanic extrusion that looks like a throat. If it is linear, I would think it a dike. It looks like a basalt plug with columnar jointing as the Tower, Postplie, and Causeway in a very large and coarse way. But that is the way volcanics evolve, when you think you have seen it all, then you see something else that is different. I think the greatest pleasure of Natural Sciences, is this evolution of what we learn, and we are still learning. Arrogance in humans that think they know everything, is regression into what we were before. Open mindedness enlightens us as we go forward.......
............So Roger, what do you feel you have shown us here. The student becomes the teacher........

...........how cool Suzie. Is your head filling up with all kinds of new terms and ideas, and when you go out you can begin to use it to read the history of our planet and all it's awesomness. Keep on keeping on, always forward, never straight..........

Thanks Nam, I'm trying, probably perused my books for an hour last night. MAJOR terms that I've never seen or used. I did have a geography of the environment course a few years ago and we did touch on how the tectonic plates were formed, how/why they moved. A bit about volcanos and we studied some about topography, I noticed all of these in my book. This instructor was really cool, we had no text book, just lecture, films, and handouts. He'd had a stint on Greenpeace so he'd been around and had a lot of first hand info to share. I'm just hoping that my geology teacher is as good with explaining everything. I just hope I can memorize everything that looks like I will have to. You know when the brain gets older, it's harder to retain stuff....for me anyway. Reading everyone's posts is interesting also. I don't always understand terms but I'll get there.