Monday, August 31, 2009

O_o

I don't usually use emoticons for post titles, but today warrents one.

Apparently, everyone at UB had an 8 or 9 AM class today, and they ALL DROVE TO SCHOOL. Meaning parking was gone by 9. Not 10, not 11 - 9 AM. And there were traffic jams. (If you've ever been to Buffalo, you'll know that traffic jams of any sort are usually pretty rare. And by my DC-area standards, Buffalo has practically no bad traffic.) UB is also pretty good with parking space, but it seems that we've acquired a whole bunch of new students who don't live on campus and haven't figured out the bus system yet.

Sheesh. I'd bike in except I'm doing physical therapy for my knees and my therapist has forbidden me to ride that much.

Sunday, August 30, 2009

A new semester

For me, this means some welcome changes. As a result of earning an NSF Graduate Fellowship, I don't have to TA this year, so I actually have more time to sit down and work on my own research (instead of spending a lot of time - including whole weekends at one point - just keeping up with grading). This also means that my committee has been encouraging me to take advantage of said funding and go for a PhD, but more on that later.

One interesting thing that happened to me last week was that I was asked to be a group leader in UB's training conference for TAs. This is a two-day gathering in which TAs, new or otherwise, meet to learn about teaching techniques, how to handle a classroom, academic honesty/dishonesty, etc. For new TAs, it might be the only chance they get to acquire a little classroom training before they find themselves in charge of a classroom (something that I wrote about last year around this time). I still find this ridiculous; just because you've made it to graduate school doesn't mean you're qualified to teach, although there are certainly a lot of great TAs out there who manage just fine.

Another unsatisfying aspect about the conference is that it wasn't geared toward science students. In fact, most of the bigger science departments at UB hold their own version of the conference, which I think would be much more useful. Fortunately, the geology department is moving toward that idea. I think a hybrid, where we invite some of the speakers from the regular conference to come and present, as well as having current geology TAs and professors work with incoming grads, would work well.

There were aspects of the conference that worked well, though. At the end of the final day, groups meet to hold micro-teaching sessions where each person gives a five-minute lesson on a topic of their choice. It doesn't need to be in their discipline; I've seen people teach their groups about how to shave, how to brew beer, how to decipher binary, and the best way to catch and eradicate an invasive saltwater fish. The catch is that these presentations are taped, and everyone gets to watch themselves (and their groupmates), and critique each other. Because it's hard to see yourself when you're in front of a class, you get the benefit of evaluating your own performance, and you get constructive criticism from your peers. (Inevitably everyone cringes to see themselves on tape - even me - but they also usually say that the micro-teaching is the most helpful part of the conference.)

So in the end, there rae good and bad things about the TA conference. For new TAs, like I was last year, it's a bit of a lifeline - maybe the only chance they'll have to learn how to teach before they're responsible for their own classroom. For returning TAs, it can be a reminder of things that they've forgotten in the grind of trying to get everything done, cover the whole lab book, grade all the papers. But as I mentioned, treating all the conference-goers as if they're automatically going to be in the position of professors isn't as helpful to TAs who are mainly going to be running labs or recitation sections, especially if their department doesn't yet have their own training session.

I am curious about what other people have experienced, though. Is this a common thing at other schools? Did any of you get special training before you found yourself in front of a classroom, or did you wing it and hope for the best? What advice would you give to incoming TAs? (If I get enough responses, I'd like to do another post on tips for TAs - so please comment!)

Tuesday, August 18, 2009

Volcano "spiders"

Most of us hate the thought of an infestation, but in the case of volcano-monitoring 'spiders', it's a safe way to gather information about active volcanoes. A number of recent articles have been talking about a new NASA program to drop instrument-loaded tripods on Mount St. Helens, putting monitoring equipment in areas that are dangerous for scientists to visit or just plain inaccessible. (See additional coverage on the Volcanism Blog, National Geographic News, and Geology News, and a photo of one of the new NASA instruments above.)

Many of you will remember "Spiderlegs" from the
movie Dante's Peak, which was a shining example of a waste of money - at least the way the scientists in the movie were using it. Trying to get a robot to climb over piles of shifting, jagged rocks is pretty hard, and if it keeps breaking while you're trying to use it, it's not worth the effort of dragging the thing to the top of a mountain. (I also suspect that NASA truly would not have appreciated Spiderlegs being kicked around - literally - during the repair process.)

As it turns out, however malfunctional their creation was on film, the moviemakers were working from reality - both NASA and the USGS have been using various 'spider' incarnations to monitor volcanoes for more than a decade. NASA tested two robots (Dante I and II, in 1992 and 1994, respectively) in volcanic craters which were real life versions of the Spiderlegs that showed up in the 1996 movie. Both were tethered robots which descended into volcanic craters - Mt. Erebus in Antarctica for Dante I, and Mt. Spur for Dante II (seen at left) - with varying success. According to the 1994 article on NASA's website, the robots were a joint effort on the part of NASA, Carnegie Mellon, and the Alaska Volcano Observatory. The article also says that
"NASA's goals with this project were to test and demonstrate robot exploration, communications and computer technologies which may be needed for future space exploration missions. Carnegie Mellon's interests include extending the results of this demonstration to other more practical Earth-based applications, including additional volcanic exploration, mining and mine safety operations, large-scale agricultural deployment and hazardous environment operations for industrial and municipal organizations. The Alaskan Volcano Observatory's goal is to obtain information on the chemical and temperature properties of the crater floor, and a higher resolution video survey map of the crater interior."
The first deployment of a 'spider' on Mount St. Helens was in 2004 (see more images at the CVO's website). These spiders were a nonmobile but portable bundle of instruments - GPS, seismic, etc. - that can't be installed permanently because of the terrain or conditions. They're relatively expendable, which more expensive instruments and scientists are not, and they function without human oversight.

The first helicopter deployment of an early spider in October 2004 (CVO Photo Archives).

A "tilt-leg" spider on the north face of the Mount St. Helens lava dome in January 2005. (CVO Photo Archives)

The early spiders only consisted of one or two instruments apiece, but new models have multiple sensors (and have spiffy software that can sort out what's important enough to send on to scientists). According to NASA's website,
A team of engineers, students, volcanologists and geologists put the system together. The team includes the U.S. Geological Survey's Cascades Volcano Observatory staff, who designed and built the "spider" hardware; Washington State University in Vancouver, where the sensor network software was written; and NASA, which developed software to make the spiders able to detect events to trigger space observations by the EO-1 satellite.
All in all, exciting new stuff - and a big improvement from the poor ungainly contraption that Pierce Brosnan was trying to coax down a bouldery slope on an imaginary volcano.

Sunday, August 9, 2009

Degassing structures in pyroclastic deposits

One of my favorite features of the pyroclastic deposits that I saw in Italy were degassing structures. A good field description of these features would be "fines-depleted pipes", since it doesn't make any assumptions about their origins (something to be avoided in the description section of your field notes!)

Branching degassing structures in a pyroclastic deposit in the Colli Albani (Alban Hills) volcanic district. (The ruler is divided into ten-cm sections.)

These pipes are formed when gases trapped in freshly-deposited pyroclastic material rise to the surface of the deposit as overlying material settles and compacts. The gases usually take fines (ash and small lapilli) with them, leaving behind tubes where clast size is larger than the surrounding deposit, and forming fumaroles on the surface of the pyroclastic deposit. The pipes can branch and join, and the ones I've seen range in size from a centimeter or two across to almost half a meter.

Fines-depleted structures galore! The side of the same cliff in the Alban Hills, with geologist headgear for scale.

An annotated version of the last photo, with the outlines of some of the degassing structures and the top of the pyroclastic deposit (overlain by some paleosols and modern soils).

If you look closely at a degassing pipe, you will often see that the clast size gets larger and the abundance of clasts (rather than ash and other fine material) increases as you move toward the edge of the pipe. This is an important clue to the processes going on in the structure; the interpretation here is that gases get concentrated around the edge of a pipe, and blow out more of the fine material there than in the middle.

Detail of the first photo; you can see a strip of scoria and other clasts along the right side of the degassing pipe, and more fine material toward the center.

It kind of brings to mind a push-up popsicle: the melted sherbert oozes up around the edges of the cardboard tube while the stuff in the middle more or less stays put.

(There should really be some oozing in this one to illustrate my point better, but apparently Fred Flintstone only gets excited about non-drippy desserts.)

One of the neatest things about these features is that you can tell something about the emplacement of the deposit. If the degassing pipe cuts through the entire deposit, it's a good bet that the deposit was emplaced all at once, whether as a single unit or through an episode of progressive aggradation. If there are multiple pipes that terminate on different levels of a layered deposit, the layers must represent different episodes in the eruption.

A degassing structure in pyroclastic deposits on Procida Island, near the Bay of Naples. Notice how the bottom of the pipe (which curves around the large central clast) seems to cut off at a layer of cobble sized rocks about a meter and a half above the cliff base. Contemplative volcanologist for scale.

Fines-depleted pipes are an easy way to identify a pyroclastic deposit, and can be a good distinguishing feature if you're trying to tell apart tuffs and lavas (providing there hasn't been so much welding and compaction that the degassing structures are obliterated). Another great example of this is the Valley of Ten Thousand Smokes, an area in Katmai National Park and Preserve (Alaska) that was filled by ash flows from the 1912 eruption of Novarupta.

Southeast up the Valley of Ten Thousand Smokes, with the rim of Katmai Caldera on the left skyline. Photo by R. McGimsey, June 10, 1991; from the USGS Photo Library.

The ash filled the valley to a depth of 200 meters, and both gases trapped in the ash from the eruption and water vapor from buried streams formed thousands of fumaroles on the deposit's surface. (These are no longer active, but still visible on the new valley floor.)

Saturday, August 1, 2009

Italy (Part II)

...and the rest of my favorite Italian photos.

The Valle del Bove on Mount Etna, with the current lava flows steaming at the summit (upper left of the photo; click to see it larger!)


Dikes in the Valle del Bove on Mount Etna.


A cinder cone (maybe two?) on Etna's south flank that was active during the 2001 eruption, with a channelized a'a lava flow at its base.

A Norman castle in the town of Aci Castello, Sicily. (This was a coolness overload for me; not only is it an 11th century castle, which makes the archaeologist in me drool, it's built on pillow lavas. How's that for geoarchaeology?)


Hydromagmatic deposits and dune structures on the island of Procida, just outside the Bay of Naples. These were chock-full of accretionary lapilli (which unfortunately disintegrated on the trip home).


The neatest spot on Procida, even if there was a lot of trash around - an angular contact between hydromagmatic deposits and the welded layer underlying fines-depleted breccias. The breccias were amazing - huge chunks of pumice, trachytes, obsidian, scoria, all packed together with almost no matrix, and grading into a "typical" ignimbrite. (Volcanologists don't understand a lot about how these are emplaced, but one of the PhD students in my department is working on it for her dissertation.)


The summit crater at Vesuvius, minus the dozen or so souvenir stands.


The Roman city of Hercolano (Herculanium), with Vesuvius in the background. We were lucky that there was almost no one visiting, unlike Pompeii (which I'll have to see another time). It was beastly hot, though.


A street in Herculaneum. You can actually still see all the charred roof beams and window frames - it's almost a little creepy, when you realize that people not only lived here, they died here.


Part of a map painted by Ignazio Danti in the Vatican Museum, showing the Aeolian islands from a 16th-century point of view. Looks like Vulcano and "Strongoli" were both active at the time!


And one of my favorite discoveries on the whole trip...the Pope's rock hammer. He's a closet geologist!*



*Okay, so it was a commemorative builder's hammer from the construction of some ostentatious overly-decorated edifice somewhere. I bet it would make a pretty decent fossil chipper, too.