Monday, October 15, 2012

Geology At Oregon State University

Update, October 16, 2012: I'm going to move stop 14 to between 4 and (currently) 5, and add Kelly Hall as stop 15, as suggested by Cassady in the comments. I walked up and took a look around this afternoon, and it's definitely worth a stop!

Update, October 21, 2012: Dana has posted the first in a series of photo supplements to this tour/post at her blog, En Tequila Es Verdad.

It's Earth Science Week, from yesterday through Saturday. Yesterday I posted Geogalavanting Around Oregon with Dana, Part II, and it occurred to me a moment ago that I should try to do a geology post a day to commemorate the occasion- lord knows I have enough material. My only concern is that I get obsessive about my reading of science, news, politics and funnies, so we'll see if I can really pull that off...

I decided for today's post, I'd post locations and descriptions of the tour of (mostly) architectural geology that I've been doing since I was an undergrad, and slowly augmented over the years. I have only a few photos at hand right now, so I'm going to skimp on those- only a few- for the time being. Hopefully I can be precise and clear enough verbally, and with FlashEarth, that you can use this guide to find all the good stuff if you're a student or work at OSU, or live close enough to visit... or if you drop by Corvallis sometime, for whatever reason. There's a map you can use for reference here. The crosshairs at the FE links are either on the objects of interest, or near the entrance to the building where they reside.

(Dana's photo supplement for stops 1-6)
1) It's probably no surprise that I generally start and end this tour at Interzone. Take a moment to look at the sidewalk (This location in the photo used in that post is near the diagonal bend in the fence on the southwest corner of the building.) Corvallis was originally laid out parallel and perpendicular to the river front, but "snaps" to the compass-oriented directions at Kings, the next street west. OSU is completely smoke-free as of September 1st of this year- I'm dubious about the effectiveness and sense of that decision, but have no interest in incurring the wrath of the tobacco police. So smoke 'em if you got 'em, before you cross the street. Head east on Monroe to 15th, cross to OSU.
2) Kearny Hall (previously Apperson Hall)- Diabase at base, sandstone in the first and second floors of the building's exterior. I don't know if the sandstone is fairly local, but it looks like it might be (in particular, the mica is very much like the Coast Range turbidites of the Tyee Formation). I suspect the diabase is local; there are numerous occurrences and  a number of quarries in the Coast Range foothills of this area. The name of this building was changed when it was seismically retrofitted a few years ago. From what I could see, and what I've been told subsequently, the building was completely gutted, leaving only the shell of the historic walls, then a steel I-beam frame installed inside that shell, and the walls anchored to that. The interior and roof were then rebuilt relying on the steel frame for structural support, rather than the exterior walls, as they had previously. This had to be an expensive project, but for a few of the older buildings on campus, I gather it's considered worthwhile to preserve a bit of history, and I'm good with that. OSU has a *long* way to go, though, in terms of seismic preparation, and I don't imagine this is feasible for many of the buildings on campus. Walk over to the grassy area in front of Benton Hall.
3) Benton Hall (Music Building), Education Hall, and upper/mid-level terrace boundary. Benton Hall is the oldest building still standing at OSU, and Education Hall is up there, too, though I'm not sure if it's the 2nd oldest. Ed has been retrofitted as Kearny was, but I've not been into it since the remodeling. Of particular interest to me, though, is this slope, which I describe as an old bank of the Willamette River. Most of campus sits on a flat, higher elevation terrace, well above any risk from flooding. Most of Corvallis sits on a lower mid-level terrace, while the other side of the river is a low terrace. Only during the most extreme flood events (like the event of February 1996) will the water encroach into downtown Corvallis.
4) Walk back across toward Kearny Hall, then west on Campus Way to Owen Hall, and into the foyer of that building. Oregon requires that 1% of the cost of building or remodeling state buildings is set aside for acquisition of art, and that often ends up being stone sculpture, such as the gorgeous serpentinite sphere above (note paving bricks for scale). There are quite a number of rock types in the sculptures here, which are symbols used in electrical engineering- the disciplinary focus of the building. Rock types include granitoids, gabbro, and either a labradorite anorthosite or larvikite- I think more likely the latter, but I'm not confident enough to make the call without hesitation. Below is a close up the larvikite(?) "H," showing the gorgeous silvery-blue schiller. Walk back out to Campus Way, turn right/west, walk past the end of Merryfield Hall, then turn right/north down the pedestrian wallkway.
5) The building on your left/west is Covell Hall. Enter the east side entrance and climb up to the first floor. The women's room is to the right on the west side of the hall (i.e. turn right as you come into the hall out of the entry stairwell, go down it a little way, then turn left) The men's room is in the exact same location on the second floor. For whatever odd reason, there seems to be a period in time where stylolitic limestone was the must-have stone for bathrooms, especially in public buildings. This creates something of a problem for an older, reserved, but intrepid field trip leader like me, who, one, doesn't want to embarrass anybody, and two, doesn't feel terribly comfortable exploring the ladies rooms on  his own. So I'd known the men's room here had some decent examples (though as I recall, not quite as nice as in the men's room near the northeast end of the concourse on the main floor of the MU- but the women's room there, I'm told, does NOT have this rock type.) However, after seeing the examples on the second floor so she knew what she was looking for, Dana says the examples in the handicapped stall of the women's room are very nice, and her photos confirm: even nicer than one floor up.When you've done the stylolites at Covell Hall, head back out the way you came in, turn back north, then walk west through the parking lot, up the steps, and through the arch between Dearborn and Rogers Hall. As you come out of the arch, stop 6 will be just ahead on your left.

6) A sweet little courtyard surrounded by Shepherd, Dearborn, Rogers, and Gilbert Addition Halls. Another of the 1% for public art bits, this is a nice piece of diabase showing both polished and (fairly, at this point- this was installed after Gilbert Addition was finished in 1981) freshly broken surfaces. As a geology person, I find this both esthetically and intellectually pleasing. It has a wondrously sensuous form, but at the same time, it's interesting to see the differences in the details you can see- or not- in the two different surfaces.

(Dana's photo supplement for stops 7 and 8)
7) Walk under the arch of Gilbert Addition to the north side of Gleeson Hall, the chemical engineering building. The rock used in the railing in the porch to that building is calcareous travertine, or tufa. If you run your hand over the top surface of the railing, you can feel how rough it has become from chemical weathering as it's been exposed to the rain for decades. Compare that texture to that of the same rock type used to line the doorway into the building, where it's much more protected, and still has the original glass-smooth texture. We tend to think of geology as intensely visual, but the fact is- often without conscious awareness of it- we use all of our senses to distinguish one rock type from another. In this case, the textural difference convinces me I'm not looking at a silicious rock, even though they're very similar looking, without a destructive method like acid or scratching.
8) Walk to the west side of the building, and around to the front on the south side of Gleeson. More travertine/tufa, but additionally, a gorgeous pink porphyritic granite, with phenocrysts of orthoclase/perthite up to an inch and a half or two in largest dimensions. Directly above the quarter in the photo is a crystal type I enjoy, which I've gotten into the habit of describing as a "butterfly twin," though that's not the correct term for it (which I've forgotten). There's another, even larger and nicer, up a bit more and to the left. We found several of these on Dana's recent visit.

(Dana's photo supplement for stops 9 and 10)
9) Cross Campus Way, and head back east to Milne Hall, the math building. Walk into the north entrance. There are at least two different kinds of marble in the foyer. Walk south through the main hall to the south entrance, and there is an extremely squarshed, folded marble- the darker greenish layers help highlight what I assume is original bedding, but these folds are tight and isoclinal following extreme pressure and mashing. Walk out the south door, then turn right/west on the sidewalk, and cross SW Waldo Place.

10) The columns surrounding the doors of Strand Agricultural Hall are made of a nice cross-bedded sandstone, and the blocks are turned in various orientations. This is an excellent spot for beginners to use cross-cutting relationships and superposition to work out "which way is up," or original orientations of the blocks. It also offers a fairly rare opportunity to see a fairly large volume of rock in all 3 dimensions, cut in regular shapes (some square cross sections, some round), and thus allowing for some good inferences into interior geometries. Walk west to the sidewalk running south, then walk south to...

(Dana's photo supplement for stop 11)
11) ...the east end of the Memorial Union. I describe this limestone as a "fossil hash," a fairly fine-grained but highly biogenic rock. Looking carefully, even without a handlens, you can recognize bryzoans, mollusk shell fragments (some recognizable as brachiopods, gastropods and pelecypods), crinoid segments and abundant fusilinids. Trace fossils, mainly burrows or perhaps feeding structures are also common. I've been told this is Salem limestone, from the Bloomington, Indiana area, but I'm not familiar enough with that rock unit to be certain. However, another geoeducator, friend, and colleague of mine grew up there, so he's probably right. Also, this is the site of my favorite gag of the walk, but I'll let Dana share that. Her reaction was a sharp guffaw, then, "That is SO stupid, but SO funny."

(Dana's photo supplement for stops 12 and 13 is here)
12) Walk along the north side of the MU to the main entrance. This rock is heavily stained with things like food and gum, and needs a good steam cleaning, but this is a granite-like rock with fairly common more mafic xenoliths in it. You need to be careful though... the stains are deceptive. As I recall, the granite in the steps of the Women's Building, the next stop, is the same, and less stained. Step through the doors into the north entryway, and take a look at the steps up to the main level. They're made of travertine/tufa, which is NOT a good choice for a pavement rock with heavy foot traffic. This building was remodeled maybe 10 or 15 years ago, and by that point, the steps were getting so dished that they were becoming a safety hazard. They were ground flat, and though I haven't seen this confirmed, I have the sense they were treated or infused with some kind of plastic or epoxy to make them more durable in an environment to which they are naturally poorly suited.

13) Continue along the exterior sidewalk west on the north side of the MU, cross 26th Street, then turn north to the Women's Building (or BVILDING, as it actually says over the entrance). Near the base of the steps on the north side is a brilliant red small monument, standing maybe chest-tall. Quartz is clearly recognizable, and the red looks to me to be alkali feldspar of some type, but the brilliance of the red is beyond any other granite-like rock I've ever seen, so I personally don't feel comfortable making this call beyond saying, "well, I think it's granite, but I'd sure like someone who knows better to speak up, 'cause that color just ain't right." The real treasure is inside the foyer, Rosso Ammonitico. (Hopefully, that link will take you to the Italian Wikipedia page translated into English.) The standard warning I give people is that the light is dim and bad at best, but give yourself a few minutes to get your "eye." Anyone who's done geology for a while knows that when you first get to a mineral or fossil collecting location, you don't see it, and you don't see it, then you find one example, then another and another and another, until finally you're wondering how you missed them at first. Same thing here. The micrite/marl has been lightly recrystallized, so boundaries are not sharp. Look for spiral shapes, and once you've spotted a couple, you'll be finding really nice examples all over the place. Also, take moment to quit looking for ammonites and notice that the floor is tiled with a really nice checkerboard black and white marbles. When you're through gawking at cephalopods, head back out to the sidewalk and turn north.

(Dana's photo supplement for Wilkinson Hall is here)
14) Wilkinson Hall/Geosciences. Near the northeast corner of the building on the outside are a few petrified logs, whose provenance is unknown to me. There is also a fairly large block of blueschist, which as I've written before, I suspect is from Bandon, Oregon. Walk into the foyer at the main (south) entrance, and on the north wall at the west end is a large relief map of Oregon. This was a fairly traditional spot to start field trips when I was in school here, as a leader could easily point out travel paths, morphological features, and destinations. Turn left/west, and walk around the the west side hallway, where a small portion of the departments mineral collection is on display in a large window. (A gallery of photos of the collection can be viewed here.) This display gets at least partially turned over on an irregular basis, so even if you've seen it before, it's worth stopping in; they may have new stuff up. Also enjoy the various cartoons, posters and cetera with which people have decorated their office doors and walls. Continue around the building clockwise, and across from the department office (south end of east hallway)  is a nice display cabinet of fossils. Exit through the main entrance where you came in.

15) Walk east across 26th St., parking lot, SW Park Terrace Pl, and more parking, then south a bit to OSU's new Engineering Center, Kelly Hall. Most of the rocks in the floor of the atrium that is the main space of this hall, and at the base and foot of the stairs, look very similar to the Indiana limestone on the east end of the MU, but with a larger component of sparry calcite (clear bits). There is also some brownish, darker limestone, which looks similar other than color. It seems to me the fossils are a bit larger and clearer- less fragmented- than those at the MU, but I think we're still looking at a fairly high-energy, wave-dominated, environment. There are some zig-zaggy looking features near the stairs that look like stylolites, too. And finally, there are lines of what I described in comments as "porphyroblastic amphibolite," and despite only glancing at them five or six years ago, that's still what they appear to be on a more careful look today.

That constitutes the core of what I generally try to hit up when I tour the OSU Campus. There are some additional spots that I may double check to make sure they're still there, such as the Dawn Redwood (Metasequioa) fossils near a living specimen at Peavy Hall (forestry), and a topographic quad mosaic at 1:62500 of most of western Oregon on the second floor of Gilkey Hall- I really should have checked to see if that's still there when I did the walk with Dana a week ago. And others. But the above 15 sites are a good core. If you spend time on or around the OSU Campus, and you think I've missed something nice, or you have questions about some stone there, please drop a comment!


Cassady said...

I would add the floor of the entire first level of the Kelley Engineering Center; the area near the bottom of the stairs and in front of the elevators in particular. Fossils everywhere. Some are fairly large.

Lockwood said...

I've been into Kelly, and noticed there were some interesting rocks- the main one I remember is a porphyroblastic amphibolite as the paving stone in the floor- but I need to go back and look more carefully. I haven't noticed the fossils. Thanks for the tip!