Spooky geology

Happy day-before-Halloween. (All Hallow's Eve Eve?)

I've got a ridiculous amount of candy (though I'm in town now, and I'm not calibrated for trick-or-treaters other than the Small Human). I've got a costume for the Small Human. I don't have a costume for myself, however. (Small Human wants me to go as a bat. Given today's stories about the causes of white-nose syndrome, though, I don't have the heart for it. Poor little guys.)

A few years ago, I encouraged my intro class to dress up as something geological. I forgot to do it this year (and it worked better when the class suggested the idea), but I got to wondering...

What would be the scariest possible geologic costume?

I think I would have to go with liquefaction. There's an earthquake, the ground turns to quicksand, buildings and people sink into the ground, and then the sand solidifies around you so you can't breath.



And then the dogs come out and eat your head.


(Images of the 1692 Port Royal earthquake from http://www.longjohnsilvertrust.co.uk/projects/henrymorgan.htm .)

Braaaaaaaains.

I'm not sure exactly how the costume would work, though. I could encase myself in sandy plaster and stop breathing... but maybe that wouldn't be a good idea.

On second thought, maybe I'll go as some obscure geology jargon that deserves to be re-animated. Nothing like a good word to eat a brain.

Braaaaaaaaains....

Earthquake in Pakistan

BBC: Scores dead after Pakistan earthquake
Scientific American 60-second-science post

There were two moderately large (M6.4, M6.1) earthquakes within twelve hours:



The earlier one had an epicenter right beside a populated valley - Khanozai, Pakistan. (Unfortunately.)



The second one had an epicenter beneath some spectacular plunging folds (WOGE-worthy, except that I'm posting the picture out of turn):



Both earthquakes had similar focal mechanisms. North-south compression (along the India/Asia collision), earth-west extension, along a strike-slip fault (again, common in Asia - see Tapponier et al., 1982, for example). Based on the aftershock locations, I would guess the NW-striking solution is the real fault. I'm curious about the relationship of the seismogenic faults to the plunging folds, though. I don't have a quick explanation... and I'm just starting to talk about faults in class this week. I would love to show the Google Earth images, but the folds show up so well on the satellite images that I should be prepared to answer questions about them in a semi-coherent way.

The earthquakes are also right at the place where the folds near the plate boundary make a sharp bend:



(By the way, does the apparent strike of the fault line up with the boundary of that basin by Kandahar, Afghanistan? It's the brown area west of the earthquakes; I don't have the cities layer turned on in my image.)

I'm not sure how that affects the faulting, either.

Reference: Tapponier, P., Peltzer, G., Le Dain, A.Y., Armigo, R., and Cobbold, P., 1982, Propagating extrusion tectonics in Asia: new insights from simple experiments with plasticine: Geology, v. 10, p. 611-616.

Edit: There's discussion of landslide potential from these two earthquakes at Dave's Landslide Blog: post #1; post #2.

Got a new science building? Want to tell me about it?

The science departments here are in a building phase. Chemistry got a new building a few years ago, biology is getting a new building right now... and just this morning, we learned that physics, engineering, and the geosciences have the go-ahead to start really planning a new building ourselves.

So now we want to know what cool things other institutions have done recently. If you know of a new science building (and especially a new geology, physics, and/or engineering building) from the past ten years, especially one that uses green building standards, make innovative pedagogy possible, or facilitates undergraduate research*, we'd like to talk to you (and maybe visit your building). (Has anyone taught with a Geowall, or learned with a Geowall? How about the new microscopy labs with digital cameras and computers, which make collaborative learning possible in optical mineralogy and petrology? Those are a few things that I know about, but I would like to know about what things are so new that I haven't heard about them, as well.)

You can contact me at my work e-mail (just google me - you'll find it) or at shearsensibility AT gmail DOT com.

*The president is interested in knowing what research universities do as well as knowing what undergrad institutions do. He wants to make sure we're thinking for the future, which is a good thing, since that's what planning's supposed to involve.

Making AGU plans

I'm going to AGU for the first time since 2000. I've tended to go to GSA instead, but AGU has been getting more and more interesting (even for someone who's primarily a geoscience educator rather than a researcher, at this point). In the past, AGU has seemed like a meeting for specialists, and if there wasn't a session on something I was actively involved in, the talks were difficult to follow. (I was completely lost by a talk about lightning that I saw on a whim eight years ago. No pictures. You know I'm a geologist... I go to talks to see the pretty pictures.)

I'm talking late (like 5:15 pm) on Wednesday. And that complicates things, because it's final exam week, and my exams are scheduled for Tuesday and Thursday. And flying in and out of Durango is time-consuming at best. I'm looking at giving my Structural Geology exam, then trying to get to the airport and get an early afternoon flight that will connect to San Francisco. And then... well, I can't realistically make it back in time for a 7:30 am Thursday intro exam or for my practical exam time for my sophomore mapping class. (Fortunately, the sophomores have to schedule individual times, so I've got flexibility there. The intro class... well, I can ask someone else to hand out the tests for me, I guess.)

I was planning to go for one day, max, because San Francisco is expensive and I've often felt out-of-place at AGU. But I'm wondering whether the conference has changed, and whether a hopeless generalist would be able to stay busy all through Thursday. (There are a number of structure sessions, even if I don't want to leave my broad area of expertise.) Those of you who go to AGU - would it be worth staying another day, to learn content for teaching (as opposed to keeping up with research related to mine)?

And are you going to AGU? Want to meet up? (That's a question both for old friends and for geobloggers.)

Edit: I've booked my flights, arriving late afternoon on Tuesday and leaving in the evening on Thursday. (There aren't actually red-eye flights to Durango, but there are flights leaving after 5 pm that connect to Durango. Wow.) So can we have a blogger get-together on Tuesday or Wednesday evening?

I've voted. Have you?

Colorado, like many other states, allows people to vote early, either by mail or at a special polling place. This year, the county clerks have been encouraging everyone to vote by early or by mail, because there is an incredibly long list of referendums, and they anticipate long lines on election day.

So I voted yesterday. (And the referendums really took forever to read.)

If you're voting by mail in Colorado, rumor has it that you need to put two stamps on the envelope or it will be returned. (That's what my local free weekly paper claims, at any rate.)

Now I just have to keep hanging up on robo-calls and push polls for a few more weeks. (Life in a swing state. Always exciting.)

Meanwhile, I've got to decide how to let students miss part (or all) of my field methods lab so they can stand in line. We're not allowed to campaign at work, but I don't think that excusing absences on election day is the same as campaigning.

(BTW, I am not at work now. Sitting at home and grading is working, but it doesn't count as state time if it's after 9 pm. And the computer is mine, not work's.)

Web resources for teaching with Google Earth

I just got an e-mail from Barb Tewksbury (actually, two e-mails; I'm on two mailing lists) telling about some new pages that she has added to SERC's Cutting Edge websites. She's been using Google Earth in Structure, and she's added a portal to collections of Google Earth teaching ideas (and great locations).

Teaching map interpretation with Google Earth
A collection of Google Earth mapping locations

There are a number of other Google Earth activities on SERC, too.

Given the fun of Where on Google Earth, plus Ron's expertise with imagery and experience using Google Earth in the classroom, and Chris Rowan's geopuzzles, I thought that the geoblogosphere might have some great ideas to add to the collection. (As for me, I've got a new Google Earth extra credit assignment this term; I give the students a latitude and longitude, and they have to tell me about it. I'm still working out the bugs, though, and I've got this immense intro class project that I still need to finish uploading to SERC before I try to write up anything new.)

Edit: I forgot about Hypo-theses' post about draping undergrad mapping projects onto landscapes in Google Earth. Neat stuff. Check it out.

Four Corners Geological Society talk tomorrow

I'm the speaker at this month's Four Corners Geological Society meeting in Durango. (The title is "Stitching plutons or magma-enhanced deformation: reaction textures, deformation, and thermal modeling from the aureole of the Victory Pluton, NE Vermont." I realize that 1) the title is way too long, and 2) at least one person reading this blog will wonder whether I have actually done anything in the past eight years. The answer, btw, is that I'm trying to wrap up some things related to the Vermont work, and I thought the FCGS members would be more interested in hearing about that than about pedagogy research.)

If anyone reading would like to come, it's in the basement of the College Union Building (the "Sub-CUB Pub"). There's a social hour at 5:30 pm, dinner at 6:30 pm, and the talk at 7:30 pm. Normally we take RSVP's for dinner, but there should be some extra space. (Let me know, though - I don't think there are many Durangoans reading this, but I could be wrong.) Dinner is $20, the talk alone is $2, and if you're a Fort Lewis College student, the talk is free.

Four Corners Geological Society website

(And to those wondering how I'm adjusting to moving all my old images to Powerpoint, the answer is... well, you know how you can scan slides? I had a work-study student doing that for some of mine, but they were scanned at the size of a postage stamp. When I opened the files, I felt kind of like the guys in Spinal Tap when the eighteen-inch Stonehendge set appeared. Fortunately, I've got new digital thin section photos, and maps and graphs that open in Illustrator, and thermal modeling results that open in Excel. But I had a moment where I wondered whether I could just do the entire thing with slides, except for the part that uses new data...)

Googling for reliable geoscience sites

Chris Rowan is better at Googling than I am. He know how to customize Google searches so they prioritize sites that he considers reliable, and he knows how to share his search engine with the world.

He's looking for suggestions for useful and reliable sites. (Think USGS-level reliability.) If you know of some that he's forgotten, please suggest them to him.

Analogies, analog modeling, and squashed chocolate

While I was away, Callan asked about geobloggers' favorite analogies. Several other people responded. I'm a week late to the party, but I want to play, anyway.

A few weeks ago, I bought a chocolate cookie from one of my former intro students at the local farmers' market.

"You like chocolate, don't you?" she asked.

"Ummm. Yeah." (I didn't have the cookie in my mouth quite yet, but I may have been drooling.)

"I remember you talking about it all the time in our class. Especially about leaving chocolate in a hot car or putting it in the freezer."

So when I came back from GSA, it was time to give my (one, tragically brief) lecture about rock deformation. (That's the sad thing about teaching Earth Systems Science. I can't spend weeks talking about my favorite things.) It's maybe a bad idea to try to explain one's entire specialty in a single lecture after spending week listening to experts talk about the newest, coolest stuff in one's field. In any case, I was having a harder time than usual distilling the subject into its most basic essences.

When I've only got one lecture to do all of structural geology, I spend most of my time talking about faults. Faults can have earthquakes; earthquakes can kill (or at least make life very unpleasant). But I try to explain that ductile deformation exists, and the whole bottom half of the continental crust (not to mention the mantle) deforms that way.

I don't try to explain ductile deformation with rocks. It's hard to imagine something as hard as a rock squishing, even when the rock looks like this:


Photo: disharmonic folds in marble below the Snake Range decollement

So I resort to describing other materials. Silly Putty is great for describing ductile behavior, but it doesn't explain how cold materials behave differently from hot materials. (Well, I don't think it does. I've never put my Silly Putty in the freezer.)

Chocolate, on the other hand, is perfect. Put a chocolate bar in the freezer overnight. When you take it out, you need a rock hammer (or some other implement of destruction) to break off pieces. Cold chocolate is brittle.

Leave the same chocolate bar in your car, though - not tonight, because it's cold out tonight, but maybe during the day tomorrow. Take it out. If it's still solid, it will probably bend in your hands without breaking. (It might have melted, in which case it's now igneous chocolate, which has its own appeal, but which messes up the analogy.) Warm chocolate bars are ductile.

I've used this explanation for years, and normally I get exactly the responses I want. And this year, the students described the cold chocolate just fine, but when we got to the warm chocolate bar...

"What kind of chocolate?" they asked.

I shrugged. "What kind of chocolate do you want?" I generally prefer dark chocolate, but milk chocolate will do, as well.

"How about a Snickers bar?"

I frowned. "You know, a Snickers bar is great in the field, especially if the bears don't eat it, but I think its behavior is a bit too complicated for this analogy."

"Ok, then, what about a Milky Way?"

The point was not getting across. "No, a Milky Way is still made of too many different things, with different behavior. I think we should make our model as simple as possible to begin with. Because, umm, we want to avoid edge effects or something." I am not a modeler myself, but I had just gotten back from GSA.

"Oh. You mean just a Hershey's bar?"

"Yes. Yes, a Hershey's bar will do."

"How about if it has almonds in it?"

"NO! Just a Hershey's bar."

I have a horrible feeling that the other students in the class will write very confusing essays about caramel, nougat, and almonds. Or at least that they will threaten to unless I feed them.

Edit: I almost forgot that I've seen an example of class experiments deforming candy: the deformation of Charleston Chews, used in Structural Geology classes by Arlo Weil from Bryn Mawr. It's a great experiment/demo/in-class exercise... but I'm told that the smell of the candy makes people feel sick. And I'm trying to get students to make positive associations with rock deformation. So maybe pure chocolate is better for the thought experiment.

THAT wasn't the search result I needed...

I'm talking about earthquakes in my intro class tomorrow. Most likely, I will tell the story about my experience in 1989 (sitting in a doorway shouting "is this an earthquake?" - which, by the way, is not the currently recommended behavior). But part of me would like to show the GPS monitoring that's being done right now. (Not that I'm quite prepared to explain vectors to my intro students... though, come to think of it, the GPS map would be a great example for anyone teaching about vectors.)

I've had the Earthscope Plate Boundary Observatory vectors plugged into Google Earth for quite some time, but I didn't remember where I'd found it. So I did what I always do: I googled it.

And my blog showed up as the second hit.

So, for anyone who goes looking for "continuous GPS google earth," here are the sites you really want:

Google Earth plug-in
GPS products from the Plate Boundary Observatory
Earthscope: Plate Boundary Observatory

(And yes, I'm doing this because I know I'll lose track of the sites again, and I figure I can always search my own blog.)

Earth Science Week: photo, essay, and art contests for all

Thanks to Silver Fox and Geology Joe for reminding me that Earth Science Week starts today. The theme is "No Child Left Inside," so the best way to celebrate would be to take a kid outside (or to donate to one of the classrooms from Maria's Donors Choose challenge). But there are other possibilities, as well.

For kids, there are two contests:

For US kids in kindergarten* - fifth grade, there's an art contest. The kids need to create some kind of visual art work portraying themselves as scientists studying the Earth.

For US kids in sixth - ninth grade, there's an essay contest on "Earth Connections." Contestants should submit an essay about how Earth's natural processes are connected to one another in the place where they live.

And grown-ups can play, too. (That is, if they haven't broken their cameras.)

United States residents of all ages can submit photos to the contest on "Earth Science Beyond Your Front Door". And no matter where in the world you live, you can submit photos for the contest on "Exploring Earth Science Around the World". From skimming the contest descriptions, I think the focus is on people exploring the Earth, rather than on the Earth alone.

The deadline for all the contests is Friday, October 17. (That would be nineteen years after the Loma Prieta earthquake, if you're counting.) Check the official Earth Science Week web page for the details about all of the contests.

*I tried to get my son to draw a picture for this contest. (He's been drawing some wonderful volcanoes lately in his school writing notebook.) Today, however, he said he only wanted to draw a picture of himself as a football player.

Blogging (post) GSA: who reads blogs?

I'm back from GSA (after a Thursday afternoon flight from Houston to Denver, on which the flight attendants probably could have gotten a lot of laughs by asking "what's in this bag, rocks?"). I'm going to try to write some more about some of the science and education sessions (including one that I wished I had seen yesterday morning, on ultra-high-pressure metamorphism) later, but this morning, I'm going to navel-gaze.

Last year, a couple of people I knew from grad school mentioned that they had run across my blog, but I didn't talk about it with most people. But this year, I think a lot of people in my age range knew that I blog. And it didn't seem something to hide or fret about. (In fact, one of my friends introduced her grad students to me because they read my blog. *waves* You're doing really cool stuff!) And at a discussion of issues for mid-career faculty members, I realized that my blog helps keep science and teaching fresh for me, at a stage in my career where I could easily stagnate.

But I also hesitated to talk about my blog to people I considered mentors of various sorts. Grad committee members, faculty at my previous institutions, a friend who is running an NSF program... I didn't talk about the blog to them. And I wondered why. Perhaps I'm still nervous about being judged. But perhaps it was my perception that there's something generational going on. My friends have used e-mail since grad school (or before), and have had web pages since they got their first teaching positions. Some have their own Facebook pages. The internet is full of many ways to communicate, some useful for some things, some useful for others, and it's not that big of a deal to use it or not. But I still expect other people to say "get off the internet and get back to real work!"

But I may be projecting my expectations rather than observing what other people think. So I've added a poll to the sidebar, to get some sense of who reads this blog. I don't collect any kind of statistics about how many people read - I know Callan and others do, but I don't. And I know Brian asked a similar question (in his old blog last year?). But I'm curious who you all are.

(And as a total aside, I ran into Zoltan Sylvester while getting coffee yesterday morning. We each had the last talk scheduled in our respective sessions, but the rooms were cold and the morning was long. We closed down the conference. Good to meet you, Zoltan!)

Edit: Apologies to the undergrads (and pre-college students) who got left out of the poll. I... well, I hadn't had coffee yet, and somehow thought that undergrads would be obvious from other info.

Blogging GSA:GPS, structural geology, and rates of movement along faults

When I was a young geologist (back when “Tertiary” was a valid name for part of the geologic time scale), we couldn’t actually watch the plates move. We accepted that they moved, but all the evidence was indirect. Weird magnetic stripes on the ocean floor. Rock magnetization that suggested that the North Pole had moved... but different directions in different places. Offset stream beds, or alluvial fans, or volcanoes.

Now, however, we have GPS. We can find where we parked our trucks We can measure the locations of points on the Earth’s surface over and over again... and we can watch them move.

Isn’t it cool when science turns out to be right?

Except... well, if you look at the data really closely, at scales smaller than plates, the geology and the GPS don’t exactly match up. Look at the faults in southern California, for instance. There’s this big, obvious Garlock Fault... and the GPS tells a totally different story.



The Garlock Fault shows up nicely on the map (and on the topography). But the GPS measurements show the importance of another feature, the Eastern California Shear Zone (ECSZ) (which is related to another feature, the Walker Lane, which shows up in GPS measurements on the western edge of the Basin & Range).

There’s also a problem if you look at the rates of movement along faults in Los Angeles. And if you’re a Californian, and you want to know how likely the Big One is, you might wonder who, exactly, to believe.

There was a GSA session that dealt with that problem. And it turns out that there are a number of ways to resolve the disagreements.

1) What if the slip rates change with time? Or if faults trade periods of activity? (That’s what seems to have happened between the Garlock Fault and the eastern California shear zone, according to a talk by Michael Oskin and Kim Le.)

2) What if the models just aren’t considering the complexity of the fault systems? Modeling faults in 3D does a better job of matching both the GPS and geologic estimates of slip rates. (Those are the results of work by Michele Cook, Scott Marshall, and Laura Dair.)

3) And are we considering the uncertainties in the rates correctly? (They are, after all, a combination of the uncertainties in the ages, the uncertainties in the offset distances, and the uncertainties in attaching ages to features. Eric Cowgill had a great talk that made that argument, and his student Ryan Gold had a nice example of a case in which it was tricky to figure out what displacements went with which ages. Eric's talk also made the point that blocks separated by faults (like in the Himalayas) can change shape internally, as other faults become active and then inactive.*)

I only sat in part of the session, but it seems as though the approaches have potential to be combined. (Could modeling be used to test whether clusters of slip on one set of faults could increase stresses on a differently oriented set of faults? Is there a way that mechanical modeling could be used to predict which faults within a block should be active and which should be inactive?) (Edit on Wednesday: Laura Dair's talk today did that, actually, modeling the evolution of the San Gorgonio Knot in southern California.)

On a human time scale, the absolute rates probably don’t make as much difference as human behavior. (Especially if you’re in southern California. Participate in Shake Out regardless of the slip rates.) But as a scientist, it’s satisfying to see conundrums resolved satisfactorily.

Meanwhile, in a session this morning, Mark Dyson (along with Sarah Titus, Charles DeMets, and Basil Tikoff) had a nice example of a case in which the GPS data, geologic maps, and mechanical modeling told the same story. It’s nice when the science works.

*Eric also had one of the best lines I've heard at the conference: he studies strike-slip faults because normal faults and thrust faults "eat their young" - they create topography, which leads to erosion, which leads to loss of part of the story. I love it.

Edit: Eric told me that he got that line from Ramon Arrowsmith. It's still a great line, but credit where credit is due, and all that.

For geologists, anything can be an adventure

It was raining at 7:50 am this morning in Houston.

That wouldn't have been a big deal, I guess, except that I'm at the Geological Society of America meeting, staying in a hotel that's a ten-minute walk from the convention center, and everyone else in the hotel was trying to get to the convention center at the same time.

Now, I'm a geologist. I'm not made of halite; I don't dissolve in water. And besides, for my PhD I had to walk uphill both ways through the snow rain for months, braving giant geologist-eating mosquitoes and reindeer that hid behind rocks and pretended to be bears. A little warm fall rain isn't going to stop me.

Except that I had my computer with me, and I didn't want to fry it. So I needed an alternate route.

I suppose I could have called a cab. But I'm a geologist. Cabs are for econ majors. And one of the other geologists mentioned that there was a tunnel system beneath Houston. So I (along with many other intrepid geologists) decided to check it out.

The tunnels connect buildings, and don't follow the streets in any obvious way. But there were maps, and it was fairly easy to see which end of the system was closest to the convention center. So off I went.

It all went pretty well until an intersection near the middle of the system, where there were three different routes that could possibly have worked. I followed some other geologists... and ended up out of the tunnel system. And the escalators that took me back down weren't working. After several tries (and some very nice help from Houstonians), I found the tunnel again. But by this time, I had lost my sense of direction, and took several wrong turns before I finally ended up at a mall about three blocks from the convention center. It took several tries to get out of the mall going in the correct direction (and it was still raining). But after half an hour of being lost underground, I'm finally here.

I wonder if I would have been better off if I had had my Brunton?

Blogging GSA: the future of jobs in geology

I'm heading for Houston and the Geological Society of America meeting tomorrow. I'm going to miss the Sunday sessions, but people following discussions of the employability (or not) of geology graduates may be interested in the abstracts from this session: Perspectives on an Emerging Workforce Crisis in Geology: Assessing a Looming Irony.

As someone who has lived her entire life in the Ivory Tower (or the Sandstone Fortress, in my current job), but who advises students headed for the Real World, I'm particularly interested in the perspectives of people in the industries that employ geologists. (Links take you to the individual conference abstracts.)

Oil and gas (Exxon-Mobil, BP)
Mining
Consulting engineering
Environmental Geology

(I'll be at the meeting from Sunday evening until Thursday morning. My talk is the last one in a session on Thursday... but at least it's possible to get back to Durango in time to teach on Friday, even when I have to leave in the afternoon.)

Edit: Some quick comments from an academic perspective, on ways that industry can ensure a supply of well-prepared employees. (I will add to this as I have time.
The kindergartener is climbing on me.)

Job fairs and other college recruiting: Colleges usually have some office that helps students find jobs, craft resumes, and so forth. Ours puts on job fairs every so often (like next Wednesday). I rarely, if ever, see geoscience employers listed with the recruiters. (Even now.) And students who have not chosen a major may hear about the opportunities at job fairs. In addition, the college career services offices may have things like electronic job listings, electronic resume services, and so forth, and may make those services available to alums - those things can make the job search process more efficient.

Don't leave those kids inside...

"No Child Left Inside" is the theme of this year's Earth Science Week, October 12-18. Our geology club is going to work with the after-school program at a local elementary school to do something on Friday, October 17 (the 19th anniversary of the Loma Prieta earthquake!). On Fridays, the local schools let kids out at 1:30 pm, and parents usually don't get home early, so lots of kids stay at Kid Kamp. Seems like a perfect fit for a rock scavenger hunt. (Or maybe we'll bring the shaking tables down and let the elementary kids build houses of sugar cubes, then knock them down.) The classroom activities here include some fun-sounding ideas. And there are lots of activities at Earth Learning Ideas, too (and on their blog, as well).

And to keep the earth sciences in the classroom during other weeks of the year, as well, Maria has picked out lots of great projects to be funded by the Donors Choose organization.

So let's get those kids dirty.