The Cave of the Winds is located at the red star on the Quemazon trail at lower left.

The whole trail travels over the Bandelier Tuff (I think it’s the Tshirege Member here), towards Los Alamos Canyon. The cave itself, which seems to have been hollowed out of the tuff by natural and human activity, is a few dozen meters down from the eastern rim of the Canyon.  It’s a relatively short hike, but it gains about 400 feet (120 m) in about  1 km, so it can be steep at times. The trail itself is really beautiful, though. The trip was led by one of the members of the Pajarito Environmental Education Center (PEEC), which sponsors trial hikes of all kinds. This one was mainly about the history of the trails , but PEEC also runs geology hikes.

Looking down on Los Alamos National Laboratory from the lower part of the trail.

Looking uphill to the west. The landscape here is still recovering from the Cerro Grande fire, which happened more than a decade ago.

Looking east down the Los Alamos Canyon at the Omega Bridge (which connects the lab to the rest of the town).

Some wildflowers along the way. Everything was blooming!

The entrance to the cave. It's a steep climb down, but not too difficult; the tuff gives you lots of handholds.

The Cave of the Winds is actually very small – just one chamber that dead-ends a few dozen meters in. There doesn’t seem to have been much evidence of water here (it’s a very dry cave and there are no speleothems), so I’m guessing it’s just a crevice in the tuff that was enlarged a bit by other processes. Our guide mentioned that it was used by the campers at the Los Alamos Ranch School, and undoubtedly homesteaders and people traveling the trails here knew about it before that.

Entrance to the cave.

Don't worry, it's just a false alarm.

Not really much to see here, but it's evident that there have been cave-ins from time to time. There was quite a bit of rubble to walk over.

Once we hauled ourselves up the side of the canyon again, it was time to get moving before the afternoon rainstorms arrived. (I was quite happy to see the rain, because it meant less of a chance of wildfires. If you read about my visit last summer, you’ll remember that I’m not a fan.)

So, I didn’t quite get to the posts I was planning on, but hopefully I can reconstruct enough of my field notes to make a start of it while I’m out here. Of course, the reason I’m out here is to bury myself in some serious numerical modeling, so blogging will have to be secondary to that. We’ll see!

The point of the excursion was to examine a progression of metamorphic facies formed under medium (Barrovian) pressure/temperature conditions. So our trip took us from Greenschist to Amphibolite to Granulite facies, all the way up to the point where the rocks gave up metamorphosing and just started to melt instead (migmatites!) There were also a few detours to mines because hey, mines are fun, especially when they have sodalite. And leucite crystals as big as your face.

Check it out!

…and much much more. But commentary will have to wait until the photo issue is resolved and I’m not trying to get ready for my birthday outing tonight.

May the fourth be with you!

Just another lovely day in downtown Los Alamos with...a big freaking forest fire in the background.

Because of the awful drought conditions in the western US at the moment, my upcoming trip to New Mexico in May isn’t looking much better in terms of my chances of avoiding close encounters of the toasty kind. I’ll be slightly more mobile in terms of stuff I need to move, but slightly less in the sense that I won’t have a car this time. So when Chuck Magee from Lounge of the Lab Lemming pointed out this article and suggested that I could take shelter in cave dwellings if there was a fire, I didn’t laugh all that hard.

Figure 3 from Heap et al. 2012, showing the results of compressive and tensile strength tests (A and B), stress-strain curves for the Neapolitan Yellow Tuff, and the results of a test to show the mass loss of each sample with increasing temperature.

Volcanic tuff isn’t a particularly strong rock, but it easy to carve and shape, which is why it’s a very popular building material. Naples, Italy is especially known for this; the Neapolitan Yellow Tuff, Campanian Ignimbrite and Piperno Tuff, all formed by eruptions of the Campi Flegrei caldera, are three of the units quarried the most often for dimension stone. In “How tough is tuff in the event of fire?”, M. J. Heap et al. take a look at a potential threat to structures built from tuff.

Volcanic hazards of living near a caldera aside, there are also secondary hazards from living in a volcanically and seismically active area, especially fire. Fires destroyed large parts of cities following the Great Kanto earthquake in Japan in 1923 and the 1906 San Francisco earthquake. The authors of this Geology paper were curious to see how the tuffs used as building materials would hold up in a fire. (Don Dingwell is especially known for testing the strength of volcanic rocks in scenarios approximating volcanic activity, so it’s not surprising that this came out of his research group!) In their experiments, they conducted uniaxial compressive and indirect tensile strength tests on thermally stressed samples of the tuffs; this basically means that they smashed the samples in various different ways until they cracked, and then recorded how heating and cooling (thermal stressing, conducted before the test) affected the rock’s breaking point.

What were the results? The authors discovered that subjecting the samples to high temperatures before the test had little effect on the strength of the rock – except in one case. The Neapolitan Yellow Tuff saw strength reductions of 80-90% in both tests (parts A and B of the figure at left), meaning it cracked a lot sooner than the other two tuffs. But why? Well, it turns out that the Neapolitan Yellow Tuff contains more zeolites than the other two tuffs. Zeolites are microporous aluminosilicate minerals which have the ability to store lots of water – in fact, they’re often used as a drying substance, or desiccant, in laboratories.

But when you dry out a zeolite, it contracts (just as a zeolite that’s taking in water will expand). If there are lots of zeolite minerals in the matrix of a rock like a tuff, this can be a severe detriment to the overall strength of the rock – according to this article, the whole rock can even expand and contract. Obviously this is not something you want your building material to do. The Neapolitan Yellow Tuff, it turns out, can lose up to 18% of its mass from those zeolites when it’s heated (part D of the figure). It also turns out that the Neapolitan Yellow Tuff is the most popular of the three building stones. The authors cite an example of the Church of Santa Chiara in Naples, which was hit by a WWII air raid in 1943; the church was constructed from the NYT and was almost completely destroyed in the resulting fire.

The authors of this study conclude with a well-supported admonition that buildings using the NYT should take additional fire mitigation precautions, due to the potential structural instabilities that could result from exposure to the high temperatures of a fire. This is a useful factor to consider not just in Naples, but in any place that uses tuff as a building material.

Because Chuck mentioned this article in reference to my upcoming trip to New Mexico, it got me wondering if retreating to a cave dwelling in the tuffs around Los Alamos would be an effective way to escape a forest fire (presumably one would resort to evacuating in a car first). The most widespread tuff in the area is the Bandelier Tuff, which is actually made up of two main members (the Tshirege and Otowi). I managed to dig up an article on the petrology and mineralogy of both, and guess what? Not many zeolites! Hooray! This means that I can take up residence in the cliff dwellings at Bandelier National Monument, assuming that Frijoles Canyon doesn’t start burning again and the flash floods aren’t an issue. At the very least I’ll have to make a trip down there to check out the fire damage, because I’m pretty sure it doesn’t look this nice anymore:

View from Alcove House in Frijoles Canyon, Bandelier National Monument

Heap, M., Lavallee, Y., Laumann, A., Hess, K., Meredith, P., & Dingwell, D. (2012). How tough is tuff in the event of fire? Geology, 40 (4), 311-314 DOI: 10.1130/G32940.1

Broxton, D. E., Heiken, G.H., Chipera, S.J., and Byers, F.M., Jr., 1995, Stratigraphy, petrography, and mineralogy of Bandelier Tuff and Cerro Toledo deposit: Los Alamos National Laboratory, LA-12934-MS, p. 33-64. http://library.lanl.gov/cgi-bin/getfile?00326203.pdf#page=38

Kranz, R. L., D. L. Bish, and J. D. Blacic (1989), Hydration and dehydration of Zeolitic Tuff from Yucca Mountain, Nevada,Geophys. Res. Lett., 16(10), 1113–1116, doi:10.1029/GL016i010p01113.

Photomicrograph of the Osiris trachyte (an ash-flow tuff from the High Plateaus of Utah), which contains plagioclase and sanidine feldpsars.

Plagioclase. From plagio-, which means ‘oblique’ or ‘slanting’ in ancient Greek, and -clase, from the ancient Greek for ‘to break’ or ‘to fracture’. Plagioclase has two cleavage planes that generally intersect at 90 degree angles, but not always – which probably prompted the ‘oblique’ part of the word.

Sanidine. From the Greek word for ‘board’ (σανιδ-, σανίς). Sanidines usually show up as flat little board-like crystals (you’ll be familiar with this if you’ve ever picked sanidines for Ar-Ar dating).

Quartz. This one’s tricky. The OED offers up several options for the origins of the word: Middle High German (quarz, quech), possibly referring to an association with a term for ‘dwarf’; and the Polish regional kwardy or twardy (‘hard’), or some other West Slavonic language (Lower Sorbian twardy, Upper Sorbian twjerdy, Czech tvrdý, all meaning ‘hard’ or ‘firm’).

Pyroxene. From pyro-, relating to fire, and the ancient Greek ξένος (xeno-), or stranger. The name is attributed to the French scientist R. J. Haüy, who incorrectly considered pyroxene crystals to be accidental inclusions in volcanic rocks. (Oops!)

Amphibole. This one has some neat origins: in Latin, it’s amphibolum, meaning ‘ambiguous’, which was probably taken from the Greek ἀμϕίβολ or amphibolos, meaning ‘thrown or hitting on both sides’ or ‘ambiguous’. This book says it’s another Haüy contribution, and that he named it ”in allusion to the great variety of compositions and appearances shown by this mineral group”. (Also, “Ambiguous Amphibole” would make a great name for a rock band.)

Biotite. Named for French scientist Jean-Baptiste Biot, in recognition for his work on the optical qualities of mica (probably as a consequence of his work on the polarization of light. Biot also made the connection between meteorites on the ground and meteor showers, and did some of the first work with electromagnets.)

Mica. In classical Latin, mica is a ‘grain’, ‘crumb’ or ‘particle’. In post-classical Latin mica means ‘little spark’. There’s also an association with micāre, ‘to glitter or shine’, although the OED suggests that the geologic name probably has to do with the classical meaning. Since mica flakes easily and often shows up in small flakes in schists and gneisses, this makes sense to me.

So this weekend I started thinking about the specialized vocabulary that geologists use. Geology is fairly new as a science, and we’ve essentially cobbled together our own language to describe a lot of the things we study. But where do those words come from? Enter the Oxford English Dictionary, which is a fascinating place to spend a few free hours (or more). Not only will it define a word for you, it will give you a really thorough etymology of where that word came from, who used it, and when. So, courtesy of of the OED, here’s a tour through the origins of the volcanology vocabulary that I use all the time. The obvious place to start is, of course,

Volcano. This was predictable to anyone who knows their Roman mythology: Vulcan was the Roman god of fire and the forge (stolen from the Greek Hephaestus, who would have made a much worse name for a volcano. Can you imagine shouting “Look out! The Hephaestus is about to erupt”? Nope, neither can I. We’ll go with the Latin on this one.) There was also some suggestion that the Island of Vulcano (below) is where most other European languages picked up the term, although the earliest reference (Samuel Purchas’ Pilgrimage of 1613) seems to be to Hekla in Iceland.

The Gran Cratare on Vulcano, Aeolian Islands

Lava. Another Latin/Italian contribution. Lavare means to wash; lava was said to refer to ‘a streame or gutter suddainly caused by raine’ and applied in the Neapolitan dialect to an eruption of Vesuvius sometime in the 17th century. We can probably assume that someone saw a lava flow sweeping down the slopes of Vesuvius and ‘washing’ away everything in its path, and drew the connection.

Lava flows on Pu'u O'o, Hawaii, 2007

Tephra. Pretty simple; tephra (τέϕρα) is Greek for ash or ashes (although I think it originally referred to ashes from a funeral pyre). Volcanologists have expanded it to include all of the air-transported particles that come out of a volcanic eruption.

Tephra (ash, pumice, and lithics) deposited during the 1902 eruption of Santa Maria, Guatemala (the scale is a bit off here, but the outcrop is a couple of meters high)

Scoria. Latin for dross, but also Greek for dung. Dross makes more sense to me, since volcanic scoria does tend to resemble the slag that you get from refining ores (and the dross is what you have left behind after you’ve gotten all the good stuff out).

The edge of a scoria cone (with welded and oxidized scoria) on Mount Etna, 2009

Caldera. There are a lot of languages with similar words (Spanish is caldera, Portuguese caldeira, and French is chaudière), but they all refer to a cauldron or kettle. Those languages, of course, stole it from the Latin caldaria (s. caldarium), which referred to a Roman hot bath or bathing room. Which makes sense overall; calderas can certainly be hot, steamy places, and the shape is similar to a large bowl or cauldron. A bit of the oldest and new origins, perhaps.

Looking out over the summit caldera of Kilauea, Hawaii, 2007

Ignimbrite. Ign- is a Latin prefix referring to fire, and imbr-is or imber is a shower of rain or a stormcloud. So the etymology implies a process: a rain of fire produced this rock. Bingo! Ignimbrites form during large explosive eruptions, generally from pyroclastic density currents (which are composed of very hot things), so this could definitely look like a rain of fire, at least at night.

Outcrop of the Sovana ignimbrite, Vulsini, Italy, 2009

Tuff. This one is a bit tricky, because it’s got Italian origins, but the Italians also used the word tufo (and the French tufa) to describe a soft or easily crumbling building stone. We now use tufa when referring to a carbonate rock and tuff when referring to a volcanic one, but they’ve apparently both got Italian (and hence Latin) roots. The Latin is tofus or tophus, a general name for loose porous stones of various kinds.

Hiking by outcrops of the Osiris trachyte, a welded ash-flow tuff on the Fish Lake Plateau, Utah, 2006

I’m thinking the next post will have to be on minerals, since I happened to look up plagioclase and sanidine and boy, do those names make more sense now! (That’s another great thing about learning the etymology of a word – the really good compound words have meanings that usually describe something pretty distinctive about what they’re naming. For me, this makes the word a lot easier to remember…and who couldn’t use help memorizing mineral names once in a while?)

Yeah, I think the title is lame, but I couldn't come up with anything more creative and I doubt anyone noticed...

So for anyone who was interested, my careers talk back in March went pretty well. It was an intro class, so I’m assuming that getting any of them to ask questions right before lunch was a success! I can’t seem to get the presentation to embed, but I can give you the gist of the thing.

Because this was an intro class, I went in with the assumption that very few of the students had any real conception of what a geologist ends up doing aside from what they see in the movies (bad examples for the most part) and what they experience in classes (teachers they see a few times a week but don’t have time to connect with). I presented a very linear concept of a geological career: take classes, get a degree, go into government or industry work OR get another degree, teach or do one of the former two options. Then I showed them the list of everyone I could find who got creative with their geologic experience. Such as…

• A science consultant for several wildly successful scifi television series
• A geologic photographer who flies his own plane (and has an M.D.)
• A geochemist who helped preserved artifacts in the Library of Congress
• An astronaut who helped repair the Hubble Telescope
• A camera operator for the next Mars rover
• A geoarchaeologist who studies natural disasters on ancient coastlines

I tried to get them really excited about this. Work in television! Travel the country in your own aircraft! Go to space! Drive robots on other planets! I think the utter coolness of the last one may have sunk into a few minds. But I did remember that this was an intro class, and  most of them probably either didn’t know what they wanted to do or had already chosen another major and just wanted a science credit. So, I ended the talk with a bit of an overview on how science in general (as well as geology) could help them find jobs, and what to do when they started looking. My key points (and bear in mind that I’m working from a fairly limited experience of being on the job market and a short career in general):

• It’s all about who you know. Seriously, this is how a lot of us get jobs. My job at AGI resulted from a conversation at a volunteer archaeological dig with one of AGI’s education and outreach employees. The aforementioned Mars rover driver (a fellow UB grad) found out about his job from his advisor’s connections. Another UB grad is now working in an outreach position at a volcano observatory in the Caribbean because our department has a lot of professional connections there. So my advice? Networking will get you noticed. Talk to anyone and everyone, especially at conferences or on field trips, and take advantage of your professors’ connections too. Make friends with everybody!
• Be prepared. You never know a job opportunity is going to show up, and you want to be ready to show yourself off on short notice. Keep an up-to-date resume and/or CV; also, keep a portfolio of relevant work you’ve done. Posters, abstracts, presentations, publications – anything. I have a whole notebook of geoscience education materials that I worked on at AGI, and you can be darn sure I’m pulling it out if I ever start looking at outreach jobs.
• Take advantage of opportunities. Sure, that unpaid internship might suck away your whole summer, but it can’t hurt to give it a try. You might narrow down your interests (I love this! vs. I never want to do this again), and you’ll make connections, and you’ll get work experience of some kind. If you can swing it financially, don’t turn down chances like this.
• WRITE. I’m not just saying this because I’m a blogger; I’m saying it because every scientist needs to be able to communicate, and writing is how we do that. If you can’t tell people why your work is important, or why you need it to be funded, then you’ll find yourself ignored and broke. Most positions requiring scientific backgrounds also require some amount of writing, and if you don’t write well, it’s going to hurt you. That said, you don’t need to write journal articles all the time. Write a diary! Write letters! Write stories! Blog! Email people! Write in any way you can as much as you can, and eventually you’ll find yourself developing a voice that will serve you well later on.
• Be imaginative and take chances. All the jobs I featured in the list above are not anything I would have thought of when I was an undergrad – but these people took a solid basic skillset and found ways to apply it to a huge variety of professions. Being adaptable with your skills and background opens up all sorts of interesting opportunities. I probably wouldn’t have applied for a job in education and outreach, given my undergraduate background was mostly in field mapping, structure and volcanology, but knowing that all that work gave me a solid grounding in the geosciences made it easier to take the plunge.
• Don’t be afraid to work up to your dream job. If you’re really lucky you might be able to snag it early on, but for a lot of people that doesn’t happen. Maybe the job isn’t available, maybe you need more skills than you have, maybe you don’t know the right people yet. It’s not the end of the world! I realized that I didn’t want to continue in my desk job even though I really liked the people I worked with (and the idea of doing outreach in general), so I knew my best course was to go back to graduate school. I have some ideas about where I want to go with my degree after I’m done – but I know that I should keep my options open!

Finally, I put together a list of geoscience career resources:

Me: Okay, I need to change this bit of code to get the program to do this, so let’s make one edit here and…

Fancy Numerical Model: (CRASH)

Me: Oops, if I change that I have to adjust this other input file. So let’s make that change and…

FNM: (CRASH)

Me: Okay, I’ve got it. If I change that variable then I have to adjust this other macro. This will definitely work now.

FNM: (CRASH)

Me: All right, let’s look at the error file and see what’s going on. It should say something useful.

Error file: (BLANK)

Me: Okay, I’ll just run it step-by-step in command line instead of using the executable. Then I can see what’s going on.

Command line screen: TIMESTEP ERROR

Me: It’s always the timestep thing, isn’t it. I can fix this. I can fix this. Easy change, right?

Command line screen: (INCOMPREHENSIBLE GIBBERISH)

Me: (INCOMPREHENSIBLE SWEARING, SOUND OF HEAD IMPACTING THE DESK)

This.

This is about the point when I start to question my sanity in embarking on a project that requires me to deal with code instead of rocks.

This weekend I reorganized some shelves, and decided to remind myself what I have and haven’t read. Quite a few of the older books fall into the second category (this might have something to do with the fact that I’m allergic to book mold), so I thought I’d make a list of what I need to work on.

Kilauea: Case History of a Volcano. Don Hebert and Fulvio Bardossi, 1968.

This is one of four books written by Don Herbert (Mr. Wizard) and Fulvio Bardossi, and is based on the Experiment science television series (for which they were the principle writers). Its first chapter gives us the gist of the book: what happened at Kilauea to spur the Nov-Dec 1959 eruption at Kilauea Iki. This was a spectacular event, forming a lava lake and cinder cone in the course of only a month… The first half of the book is dedicated to the science of volcanic eruptions – meant to give the reader a grounding in the tools that volcanologists use to draw conclusions about volcanic activity – and the second half is dedicated to the 1959 eruption and the activity that follow it. The book is well-illustrated, full of USGS photos and firsthand accounts from the scientists at the Hawaii Volcano Observatory, and it looks like it will be a pretty engaging read when I can get to it.

It Began With A Stone: A History of Geology from the Stone Age to the Age of Plate Tectonics. Henry Faul and Carol Faul, 1983.

I have to admit, I have this book mainly because my petrology professor in college noticed it mentioned Sir Archibald Geikie (we were assigned minerals to report on for one of his classes, and mine was geikielite). But it covers a lot more than 19th century Scottish geologists, looking over the history of geologic science from Herodotus to da Vinci, Werner to Lyell, Powell to Wegener. It even looks at the early years of geology departments at American colleges, geology in the Civil War, and early geological work in Canada. I like that it includes a few chapters at the end summarizing the current state of geology, although oddly the current state seems to the authors to end at Wegener’s continental drift theorizing in the 1960s. (This could be because the author died before completing the manuscript, however.)

Legends Of The Earth: Their Geologic Origins. Dorothy B. Vitaliano, 1973.

This is one I’m really looking forward to sinking my teeth into. Volcanologists (and geologists) often draw on oral tradition to help draw connections between geologic events and historical records (or the lack thereof), and this book is a wonderful collection of stories with connections to geology. The author calls them “geomythology”, and she covers myth and folklore describing everything from landforms to earthquakes to volcanic eruptions to floods. Hawaiian legend is especially featured, as well as the eruption of Santorini and its connection to the Minoans and the “lost” city of Atlantis. There is also mention of Icelandic and Maori legend, as well as Mediterranean tales from Italy and Greece and Native American folklore from the American West.

Chains of Fire: The Story of Volcanoes. Kent H. Wilcoxson, 1966.

This book seems to be a tour of volcanoes around the world, and it has the best chapter titles I’ve come across yet. I mean, who wouldn’t want to read about “Mexican Volcano Babies” or “Vesuvius: Monarch of the Mediterranean” or “Volcanoes Made In Japan”? I’m particularly partial to the fact that the chapter about Central America mentions Santa Maria prominently, although I’m less partial to the author’s choice to try and link the 1902 eruption there to the eruption of Mount Pelee in the Caribbean (and other activity in Central America and the Antilles arc). Still, the author seems to have drawn heavily from first-hand accounts of activity as well as scientific papers, so the basic information should be accurate even if there’s a bit of speculation involved.

So, there  you have it – my reading list for the next few weeks, providing I don’t just get swamped with papers on fluid dynamics and mineral stability fields.

Looking southwest along the lakeshore cliffs

The scenery is lovely here – to get to the fossil site, you take a short hike through woods that border the creek and the marshy areas at the lake outlet. But the best part is at the end of the walk: Trilobites!

Well, trilobite bits.

Eighteen Mile Creek is one of the best places in Western NY to find trilobites (and other fossils as well). It exposes the Wanakah Shale, another Devonian unit. Here’s what UB’s Geology Department website has to say about it:

“At its type locality north of Eighteen Mile Creek along Lake Erie shore, the Wanakah Shale consists of about 19.8 m of medium gray, soft, fossiliferous shale and shaly mudstone with several calcareous bands and zones of larger concretions. The highest beds of the Wanakah Shale exposed just below the Tichenor Limestone contain a high diversity fossil assemblage termed the Demissa and Stictopora beds of Grabau (1898, 1899). These units yield over 80 species of macrofossils and are particularly rich in brachiopods and bryozoans.

“At Eighteen Mile Creek, the Tichenor Limestone is a resistant, 30-40 cm thick ledge-forming crinoidal biospharite and biomicrite. It contains numerous large rugose corals (Heliophyllum, Eridophyllum) and heads of the tabulate coral Favosites hamiltoniae, large crinoid columns, fenestellid bryozoans and brachiopods. The large bivalves Plethomytilus, Actinopteria, and Goniopora, are locally abundant in the upper surface of the Tichenor Limestone.”

To give you a better idea of the stratigraphy, here’s a diagram of local Devonian units:

Courtesy of Dr. Jorg's sed/strat website (http://www.geology.buffalo.edu/contrib/people/faculty/gly216trip.htm)

Walking along the beach is one easy way to find fossils, but you can also bring along a rock hammer and split chunks of the shale apart (this tends to be where the trilobites show up). We did both, and here are some of our finds:

Brachiopods are really easy to find on the beach, since they seem to stand up to wave action pretty well. I think this is Athyris spiriferoides

Rugose (or horn) corals are also really common, in both the shale units and the limestone.

Occasionally, the rugose coral gets REALLY BIG.

A slice of a rugose coral - it looks a little bit like a really big crinoid stem from this angle, but the crinoids here don't get that large.

There are a lot of concretions in the shale, and they're usually a little crystalline at the center. The color bands are also really common.

Despite the fact that it's shale here (and presumably a low-energy environment), it's hard to find trilobites that aren't broken up. So you see a lot of trilobite butts (pygidiums? pygidii?)

But just occasionally, you find a really awesome trilobite in one piece - like this one! A Phacops rana rana, if this website is correct: http://www.fossilguy.com/sites/18mile/

I didn't even have to break any rocks to find this guy - he was just laying there on the beach.

I think he's a little pyritized, which would explain why he stuck together when all his buddies were going to pieces.

Oxide minerals (maybe pyrite?) tend to show up in this botryoidal form here. These are all over the beach as well, and I think they can be just as interesting as the fossils!

Because Buffalo is an industrial town, there are also some interesting remnants of that industry on the Lake Erie shoreline, like these glassy bits of slag.

But everyone comes for the fossils. And it was a beautiful day for it!

For more information on Western NY Geology (and fossiling at Eighteen Mile Creek and other locales), check out these links:

• Geology of Western NY Guidebook (a bit old, but worth a read!)
• Devonian Stratigraphy and Fossil Assemblages of Western NY
• Fossilguy.com’s page on Eighteen Mile Creek collecting

It’s pretty easy to nitpick a movie or TV show for science mistakes, but it’s an interesting challenge to turn the nitpicking into an opportunity to learn instead. Instead of saying, “That’s wrong!”, it’s ultimately much more satisfying to say, “How could it work in the real world – and if not, why?” One example that stands out in my mind was a paleontology lab I did in undergrad after we watched Jurassic Park. The scene where our heroes are chased (in their Jeep) by a cranky Tyrannosaurus brought up a few questions while we were watching it – namely, “Are you really telling me they couldn’t outrun that thing?” So our professor had us do a lab to calculate, based on what we knew about T-Rex physiology, what the dinosaur’s top speed actually was. (If I’m remembering right, it was around 25 mph, so it might have been a much shorter chase scene. I can just imagine the T-Rex standing there going “screw this, I’m going to go eat something slower.”)

So here are a few of my favorite geology movies, and potential “learning moments” that we could draw from them.

The Core

There are a lot of things about this movie that make me cringe (other people have covered them extensively), but I think my favorite moment is early on when Dr. Keyes is describing the function of Earth’s geomagnetic field using a peach and a homemade flamethrower. I wish I could find a way to do a demo like this someday, because demos can be an effective way of communicating a concept (especially if they’re flashy or explosive). Without our magnetic field, we might not necessarily burst into flame, but we would be exposed to cosmic rays and ultraviolet radiation that would certainly cause some problems. Solar weather (like the big storm that’s going on right now) would probably do more damage than it does now. And using a peach to represent the Earth is actually not a bad example: a peach has a very thin skin compared to its innards, just like the Earth’s crust and mantle, and the peach pit comes close to being the size of the core, if you have a smallish peach. (The analogy stops there, however, since the outer core isn’t solid.)

Dante’s Peak

For the most part, this isn’t a bad depiction of an explosive volcanic eruption, albeit one that occurs on an accelerated timescale. (There are even lahars!) But one big sticking point is the arrival of Hawaiian lava flows on a Cascades volcano. Now, this is something you’re not likely to see happening over the course of one eruption. But there are conditions under which you can get explosive eruptions and lava flows at the same volcano over the course of many eruptions.

"Gareloi Volcano, elevation 1573 m, in the western Aleutian Islands, Alaska. Levied lava flows from a 1980s eruption drape the south flank of the southern summit crater. The white zone on the crater headwall is an extensive fumarole field." From the Alaska Volcano Observatory website, http://www.avo.alaska.edu/images/image.php?id=1992. The summit craters produced explosive eruptions in 1929, and the lava flows were erupted between 1949 and 1980.

How, you ask? Well, there are a number of factors, but most of them center on the magma fueling the eruption, and its viscosity. Viscous magmas tend to contain lots of volatiles (gases like water vapor and carbon dioxide); more phenocrysts or a higher silica content also make the magma “stickier”. Temperature can play a part as well, and magma with a higher silica content also tends to be cooler and has a harder time flowing. So if a volcano erupts different batches of magma with variations in these factors, the eruption will behave differently. The differences could be due to magma having more time to cool and crystallize in a magma chamber, or it could be that a new, hot magma of a different composition was introduced to the reservoir. It’s possible for magma to evolve during the course of an eruption, but usually not on the scale of hours – so you’re not going to get simultaneous explosive and effusive activity like Dante’s Peak portrays.

Volcano

Image from http://imcdb.org/vehicle_161312-Ford-Aspire-1994.html

There are a couple of lessons to learn from this one. The first concerns the (lack of) connection between volcanic eruptions and tar pits. The La Brea Tar Pits featured in the movie are formed from petroleum released from the oil-bearing mudstones of the Miocene Monterey formation, at the bottom of a series of marine and fluvial deposits – not exactly volcanic material. In fact, the closest volcanoes to Los Angeles are in the Coso volcanic field, over 100 miles away (and they haven’t been active in the last 10,000 years). There are certainly a lot of faults in the Los Angeles area – and we know that faults can provide pathways for magma in volcanic eruptions – but that does require actual magma. If there were magma under Los Angeles…well, that would be another story! (And another excellent geologic reason not to live there.)

The interaction between Anne Heche as our heroic geologist and Tommy Lee Jones as our even-more-heroic Office of Emergency Management official is the second thing that I find merits discussion. The role of volcanologists in dealing with eruption monitoring and hazard mitigation is a tricky one. Things can get messy in an organizational and legal sense when scientists double as decision-makers in hazard mitigation situations, so what happens is that scientists take the responsibility of informing civil authorities about the hazards, but leave the decision-making to the crisis managers. It’s our responsibility to make sure the crisis managers are adequately educated about the dangers and possible repercussions of a particular situation, but we tend to stay in the background when it comes to calling the shots. The USGS’s Volcano Disaster Assistance Program is a prime example of this – their volcanologists will help set up monitoring equipment and develop hazard assessments, but they don’t call the shots.

Journey to the Center of the Earth (new)

This movie does require some major suspension of belief. But when I was working at AGI before going to grad school, we were actually asked to help create an educator’s booklet to be used along with the movie, and that required me to look for topics that we could turn into lessons.

A few that made it into the booklet are:

• Plate tectonics – Brendan Fraser’s character is a seismologist who runs a “Center for Plate Tectonics” at his university. The visual highlight of the Center is, of course, the nifty computer displays that show seismic activity around the world.
• Rock types – Our heroes start off their journey in Iceland, where we get to see lots and lots of lovely volcanic rocks. But when they enter an abandoned mine and begin descending into the Earth, they start seeing other rock types (including a few notable minerals like feldspar and muscovite). So we added a section about different rock types and where they form (although because the booklet was drawn in comic-book style, the sedimentary rock kind of looks like a potato, but it is pretty hard to draw a cartoon of a rock).
• Earth structure – “What’s really in the center of the Earth?” is the question posed here, because I think everyone who watches this movie has some idea that it’s probably not hollow and full of dinosaurs. So there’s a basic cutaway diagram accompanied by a little description of how we know what the structure is (seismology, geochemistry, etc etc.)

I really liked that the people making the movie wanted to help teach as well as entertain, and I think the booklet was a great compromise between the movie’s fantasy world and our real one. (You can still download a PDF from AGI here.)

It’s a balance that’s tricky to strike. As I mentioned before, it’s really easy to spend all your time complaining about what’s wrong in movies and TV, but it takes much more time and effort to use those mistakes as an opportunity to learn about what’s actually right. (It took me several days just to come up with the discussion in this post, and I’m familiar with the movies and the science!) I’d really like to see more entertainers taking the route that Walden Media did with Journey, and invite the experts to help make the science better. We’d love to help!