Friday, January 29, 2010

1K

This is the 1000th post on NOVA Geoblog.

I passed up the opportunity to engage in anniversarial navel-gazing this past December with the blog's second birthday, opting instead to dish out some recognition to other corners of the geoblogosphere. A thousand posts, being an arbitrary but satisfyingly round number, encourages me to think about what I'm doing with this blog, and where it's going. Today, if you'll indulge me; I offer a few reflections (#1-4) and a request for feedback from you (#2, #5).

1) I've been gratified with all the positive feedback I've gotten (via comments, via e-mail, and in person), mystified at the persistence of some readers in posting argumentative comments, disappointed overall at the lack of commenting, and annoyed at the increasing number of spam comments, which I delete as soon as they come in (a chore). Thanks to everyone who considers this site worth taking the time to read.

2) I'm curious who's reading. I get data that suggests a lot of people are stopping in, but not a lot of people leave comments. If you're a regular, but you don't leave comments, let me extend an invitation to you to say "hi." You can do this via the comments section below, or shoot me an e-mail if you don't want to be all public about it.

3) I enjoy blogging, but I'm also a bit compulsive about it. This blog has existed for 770 days, and the 1000 entries I've posted over that time works out to an average of ~1.3 per day. I'd like to tone that down a bit. In the future, I'm going to give myself permission not to post something every single day. Brace yourselves: I'm going to start applying the brakes.

4) This summer I hope to launch a new geology vodcast series. This has been in the works for some time, and I'm excited that it is finally moving forward. I'm looking for suggestions for a clever title for the series (feel free to leave a comment below if you have a good idea what to call it). It will be available via iTunes and a dedicated YouTube channel. I will also embed the YouTube videos in blog posts here.

5) Lastly, to better determine the future of this blog, I have put together a 5-question survey that I would like to ask you to complete. It is totally anonymous, and will take only 3 minutes of your time. I will leave this survey open for the next 2 weeks, but I ask you to please take the time now to click the link above and complete it. This is for everyone who is reading these words: it's not just for hard-core geologists or for other bloggers. It's for all readers. Thank you!

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Wednesday, January 27, 2010

Patagonia reference post

Tuesday, January 26, 2010

Masoleums and Monkeypuzzles

This is the final post about my trip to Patagonia. Our final stop was in Buenos Aires, the capital of Argentina. There wasn't much of geological interest that I saw there, but you might like to check out these images of the Recoleta Cemetery, a famous cemetery there. It's full of charming masoleums which are unique in design, and in various states of repair. (Eva Peron is buried here, which is what draws in most visitors.) Here's a view down one of the labyrinthine alleyways:
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This masoleum looks like a miniature cathedral:
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Several had art noveau details:
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This one had an awesome stained glass onion dome bulging out the top:
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Two-faced angel statue:
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This caught my eye:
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The grave belongs to an Argentinian surgeon, Francisco Muniz, who was also into paleontology:
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Muniz apparently discovered the first glyptodont (though was not the first to publish it), and corresponded with Charles Darwin. There's a neat little review of his life here, at a website documenting the people interred at Recoleta Cemetery (a great resource if you ever visit it yourself).

Rising from a prominent intersection of pathways in the cemetary was this prominent Araucaria, which I think is a monkeypuzzle tree:
Graves_03

Monkeypuzzles are native to Patagonia, though other members of the genus may be found in New Caledonia, New Guinea, Norfolk Island, and Australia. I love monkeypuzzles: mainly for their awesome name, but also because they look like my idea of what prehistoric plants should look like. Here's one in El Calafate that someone decorated for Christmas:
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Closer in, to see some details of its scaly leaves:
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Perhaps this is a good image to close out the Patagonia series with, considering it blends the exotic monkeypuzzle with lovely old traditional holiday spirit (at least in my culture). What do I take from this?...

...Amid the prickly hazards of travel, you can find some exceptional gifts.

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Monday, January 25, 2010

Perito Moreno Glacier

Yesterday we looked at some other aspects of Argentina's Parque Nacional Los Glaciares (and the nearby town of El Calafate). Today, some pictures of ice.

Let's orient ourselves first, courtesy of some satellite imagery via Google Maps:

You can see the bright blue of Lago Argentino, including its southern arm, the Brazo Rico. Separating the Brazo Rico from the main part of the lake is the Magallanes Peninsula. And poking out from the white mass at left (the South Patagonian Ice Field) is a nice big valley glacier, the Perito Moreno Glacier. Notice how it pokes right into the Magallanes Peninsula, like a pin approaching a balloon. Occasionally, it surges forward and smooches the opposite shore, cutting the Brazo Rico off from the rest of the lake. When this happens, some spectacular collapses can occur.

The Perito Moreno Glacier is remarkably stable, due in part to its large catchment area and relatively narrow zone of ablation. This means that a bunch of park infrastructure has developed on the Magallanes Peninsula: viewing platforms and docks. The glacier moves forward at the same rate it loses ice through calving/melting: very consistent. We started off with the boat trip up to the glacier's terminus. Here's a view of the boat from above:
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...And a view of the glacier's face from the boat:
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Ice meets bedrock (plants watch warily):
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Looking north from the viewing platform:
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A little panorama (two shots spliced together):
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So, at this point, I hope I have established that Perito Moreno Glacier is very accessible and very photogenic. It is also a lovely shade of blue. Thank you very much.

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Sunday, January 24, 2010

A few photos from Argentina

When you cross the border from Chile into Argentina, you see this sign:
Perito_01
If you aren't familiar with "Las Islas Malvinas," that's because they go by another name in English. Perhaps the detailed map will help clarify the location? The sign refers to the Falkland Islands, currently held by the United Kingdom. So the sign translates to, "The Falklands are Argentinian." The British and the Argentinians faught a war over the Falklands in 1982. The UK won, but Argentina maintains their claims of sovereignty. And as soon as you enter Argentina, they remind you of it. I think they hope you will take pictures of the sign and post them on your geology blog so the world is reminded of what they consider to be an imperial injustice.

The bus ride from Puerto Natales to El Calafate was long -- something like five hours. It went through some very empty country:
Perito_02
As we headed north, with the mountains to our west and wide-open plains to our east, I was reminded of Montana, specifically the Front Range southeast of Glacier National Park. It was very familiar feeling.

The landscape was semi-desert, as the eastward-moving air is drained of its moisture as it crosses the Andes. The rainshadow effect leaves this an area of steppe. The golden grasses draped on the dry hills bring to mind similar landscapes in Mongolia or Africa.
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And there are even some birds that you might mistake for African species:
Perito_04
That's our best of many lousy pictures of the Lesser Rhea, also known as "Darwin's Rhea." It's a ratite bird, related to ostriches, emus, cassowaries, kiwi, and elephant birds (the last of which are extinct). The coolest rhea sighting we had was a family of little ones following their mom. The little ones look just like scaled-down miniature adults: Comical!

We stopped at an estancia (ranch) before entering Parque Nacional Los Glaciares, and Lily made friends with a horse there:
Perito_05
She used to have a horse on Hawaii, so this was sweet to see. When we walked off towards the rhea, he followed along, looking for more lovin' from his new American girlfriend.

We were in Argentina to see the massive Perito Moreno Glacier. It is the #1 tourist attraction in Argentina, and is located in Parque Nacional Los Glaciares ("The Glaciers National Park"). Here's our first view of it:
Perito_06

Now here's a test to see how true-blue your geological inclinations run. When you looked at that last picture, did you think to yourself, "What's up with those strata in the lower right? Are those turbidites?"

Yes, indeed. They are:
Perito_07
Alternating sand (blocky) and mud (weathered into low relief) remind us of the Magallanes Basin, which (like most geology) does not stop at the border...
...LA CUENCA MAGALLANES ES ARGENTINA Y CHILENA.

Um, there's two clear joint sets there too.

Around the corner we saw some bivalve fossils and a few clastic dikes ("injectites"). Here's a small clastic dike:
Perito_08

When I brought up clastic dikes the other day when discussing Torres del Paine, Brian responded with some injectite photos of his own. You should check those out. Here's a bigger one from P.N. Los Glaciares:
Perito_09

I've got a ton of photos of Perito Moreno Glacier to show you, but it's really worth saving them for a second post. For now, let's just say: "We went and looked at the glacier for several hours and were very impressed." ...More on that tomorrow.

Then we were bussed back to El Calafate, the town which serves as the main access point for the park, and walked from our hostel towards downtown for some dinner. Along the way, we saw this cool outcrop:
Perito_20
That's very-poorly-lithified silt, peppered here and there with a few cobbles and boulders. The clasts bear scratches, suggesting they are glacially-delivered. The town of El Calafate is on the shore of a big lake called Lago Argentino, and I interpret this outcrop to mean that the lake was much larger and deeper in the past (perhaps dammed by a moraine which has since been partially breached?). In this deeper, earlier version of the lake, icebergs calved off of Perito Moreno Glacier and floated out to melt and drop their sedimentary loads in the offshore sediments. The big boulders and cobbles are therefore dropstones, though I wasn't able to confirm this diagnosis by looking for squished or truncated sedimentary laminations beneath them. (Given that this is earthquake country, I didn't want to be standing underneath those boulders for longer than it took to snap a photo!)

That evening, we had a really world-class meal. Salads and breads and fine Argentinan wine (we skipped the Mendoza stuff and got the Patagonian label, "Saurus." (Yes, as in lizards -- as in "giant, fossilized, terrible lizards"). And for the main course? Well... let's just say that if you're a vegetarian, you should probably stop reading at this point.

The Patagonians herd a lot of sheep, and so they eat of lot of lamb. They have one particular method of cooking this lamb which I was very keen to try because it seems so utterly brutal. Meat is murder, as they say: delicious murder. I am quite aware of the loss of life that comes with the consumption of meat. I have hunted, and I have killed animals in order to eat them. Many people opt not to think about this, and to access their meat in a box or a bag. But to the Patagonians, the death of their animals is both obvious and inoffensive. They slaughter their lamb, gut it and skin it, and then (this is the part that's brutal) they string it up to an iron cross, which is then tilted over a campfire so the lamb can roast slowly. They call it "crucified lamb."
Perito_21
It was delicious -- though the photo may appear shocking to some readers. But, hey: Catholics claim to eat crucified flesh every time they take communion, right? (Apologies in advance to all the transubstantiationists that I just offended.) ...Back to the lamb: I have a special place in my heart for the taste of mutton (I served in Peace Corps Mongolia in 1998-1999), and that familiar gamey tang was present here as well. But it was so much more tender, and served with a garlicky oregano olive oil-based sauce. Oh man, it was good. (Mongolians could learn a lot from Argentinians about how to spice their lamb.) I devoured it, and Lily had to roll me down the street, back to the hostel. Mmmmm....

Okay -- tomorrow you'll get some glacier photos.

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Saturday, January 23, 2010

Steve Mirsky on Inhofe and Comfort

In the new issue of Scientific American, vodcast host and prodigious author Steve Mirsky takes on James Inhofe and Ray Comfort. No news here if you're the sort of person who follows climate politics and creationism shenanigans, but his short essay is pretty funny.

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Torres del Paine, el ultimo dia

Well... after a week in Parque Nacional Torres del Paine, it was time to head out of the wilderness and back to the relative civilization of Puerto Natales. We woke on the seventh day, and were pleased to see that the sun was hitting the Cuernos del Paine in a pleasing fashion:
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Our tent in the foreground of the Cuernos del Paine:
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We made our last batch of camp coffee and our last batch of oatmeal, and then started hiking out. As we walked along, we saw some interesting geology.

Here's a decent little weathering rind. Notice how the initially rectangular profile of this clast is being weathered towards a progressively more bread-loafy shape:
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A small dextral fault offsetting turbidite layers:
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Looking up into one of the valleys we passed on our way east, we saw an intact glacial end moraine sealing the valley shut.
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I'm used to seeing these depositional features bisected by streams, but this one looked just like a wall built perpendicular to the valley trend. Erosion hasn't yet undermined it.

We arrived at the Torres area and fortified ourselves with Snickers bars dipped in peanut butter, then strolled on. There were a great many people there: somewhat shocking to the dirty backpackers...

As we hiked out from the Torres campground/village/tourist extravaganza to the entrance station at Laguna Amarga, we turned around and saw the Torres themselves, namesakes of the park, faintly through the misty distance:
TdP_day7_07

Several kilometers on, we approached the Laguna Amarga Ranger Station, which is situated next to a lovely syncline in the Cerro Toro conglomerate:
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Another view, from lower elevation, and closer to the axis of the fold:
TdP_day7_08

Our time in Torres del Paine was unforgettable. Backpacking the Grand Circuit was a travel experience I would recommend to anyone with the ability and temperment to camp and hike in such gorgeous surroundings. It had been the primary goal of our trip, but we weren't done travelling yet. We headed back to Puerto Natales on the bus, and gorged ourselves on pizza that evening. We did laundry, got showered up, and slept like hibernating bears. In the morning, we boarded another bus, one that would take us across the border into Argentina...

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Friday, January 22, 2010

TV weathermen skeptical of climate change

Food for thought: check out this excellent article in the Columbia Review of Journalism ("Hot Air," Jan/Feb issue). Subtitle: "Why don't TV weathermen believe in climate change?"

Hat tip: Anthony Leiserowitz at the Yale Project on Climate Change, who is quoted in the story.

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Torres del Paine, day 6, part II

You'll recall that our sixth day in Torres del Paine National Park had us hiking east from the Paine Grande Lodge. We hiked up over a ridge dividing Lago Pehoe from another turquoise-colored lake, Lago Nordenskjold:
cuernos_26

At the so-called Italian Camp, we dropped our packs, and went for a small side hike. We turned to the north, and hiked up the French Valley:
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The object of this day-hike was to see some glacier calving. The French Valley is famous for this: you sit back and watch, and big chunks of ice spall off the glaciers, crashing hundreds of feet below onto the rocks. A few seconds later, a sound like thunder reaches you: it was this that we came to experience.

Anybody seen a glacier around here? Rumor is that it was JUST here!
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[The line demarcating vegetation above from bare rock below shows former height (and presence) of the glacier.]

Here's a look at the amphitheatre where our glacial show would be performed:
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As the clouds cleared a bit, we could see an astonishingly thick cornice of snow/ice atop the mountain peaks. All the valleys up top had been filled in and smoothed off, and there was this white rim atop the black rock. The cornice is probably 40-100 feet thick in this photo:
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An annotated photo of the area where we were observing the action:
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What happened here was that a much larger glacier (see the vegetation line back a few photos) ablated away, splitting into two upper disconnected feeder glaciers, and a lower glacier which is now semi-buried in rocky debris (talus) and ice spalled off the upper glaciers.

A closer look at the annual growth layers revealed in the lower part of the glacier:
cuernos_25

We soon saw some calving events. They were quite cool. Big booming noises, ice explosions seen through binoculars, eating chocolate and almonds. We were happy. Then we heard a roaring noise, like an airplane going overhead. We looked at the glaciers: nothing. What was making that noise? Then, from above, we saw it: coming down out of the clouds was a huge billowing white mass. Apparently, it was coming down from the cornice of snow atop the mountain. An avalanche! An honest-to-goodness avalanche! I have never seen one before; I was giddy at the spectacle. It looks just like a turbidity current, people, but it is white!

It was a magical thing to witness: watching it spread out and poof outward in hundreds of little round turbulent vortices. Everyone in the valley cheered: "YEAHHHH!!!!!"

Tough act to follow... but: Just east of us were the rugged Cuernos del Paine, a series of glacial horns made more photogenic by the pink stripe running through their middles, like a WWF Championship Belt:
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This pink stripe is a granitic intrusion, approximately 12 Ma (Miocene*). Here is another photograph of the Cuernos, where the granite is very obvious:
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We walked along the north shore of Lago Nordenskold towards the Cuernos campground...
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Across the lake, some nice folds were visible:
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The Cuernos campground is in this little nook. A lovely place to spend an afternoon and our final night in the park:
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And it has very nice views of the Cuernos del Paine:
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Seeing the Cuernos was the fulfillment of a decades-old dream for me. I think I saw them in an REI catalog (or perhaps a Patagonia catalog, hmm?) back when I was in college, and thought, "Wow. There's a place on Earth that really looks like that? I gotta go... someday." What I didn't expect then, and was pleased to see now that I was there, was the excellent evidence of stoping, one of the processes by which magma chambers enlarge their size and intrude into other rocks. Stoping is where chunks of the wall rock ("host rock" or "country rock") are broken off by inquisitive fingers of magma, and the liberated blocks (now xenoliths) drop into the magma chamber. Here, you can see (white arrows) some of these splurtles of granite working their way into cracks at the top of the magma chamber:
cuerno_02

If these fingers of granite connect up, they separate the block of rock beneath them from the country rock (a form of physical weathering, like root wedging!). More dense than the surrounding magma, the resulting xenoliths sink. If the magma is still rather fluid, the xenoliths may now pile up on the floor of the intrusion. If it's getting to be mushy and semi-crystalline, their downward flow may be retarded, like a slice of banana trying to sink through thick oatmeal. As the granite crystallizes into rock, those xenoliths will be trapped somewhere between the ceiling (source area) and the bottom. Check out the diversity of xenolith positions (white arrows) displayed on this Cuerno:
cuerno_03

Great looks at stoping here: some have fallen, some are still beginning to fall. I could easily have spent another two days just hiking along this contact, looking at this intrusive relations.

We spent our final night in the park enjoying the sounds of a nearby waterfall, nature's white noise machine. Only one more day in Torres del Paine...

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Meteorite falls in Lorton!


On Monday, a meteorite crashed into a doctor's office in Lorton, Virginia! Smithsonian scientists confirm its identity as space rock. 220 mph at the moment of impact. Super cool.

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Thursday, January 21, 2010

NatGeo on Patagonia

Good timing! National Geographic's new issue (which we got yesterday) discusses many of the same regions of Patagonia that I've been describing here over the past two weeks. You won't find any graded beds in their pages, but they do have some spectactular imagery of the Grey Glacier (via NASA) and the Chilean coast. The NatGeo website has a nice slideshow of photos by Maria Stenzel. The story's lead image is... Torres del Paine.

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Torres del Paine, day 6, part I

You will recall that the first photo I showed you from Patagonia was this one:
sunrise_Dec_27

That's from just outside the Paine Grande Lodge, where we stayed for our fifth night in the park. I rose at dawn and was fortunate to have the camera handy for a few minutes of good low-angle pink/orange light. By the time the coffee was finished, the sun had risen higher, and the "golden hour" had finished. The mountain now looked like this:
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We began the day's hike, headed east along the southern face of the Paine Massif, aiming for the legendary Cuernos ("Horns") del Paine:
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A last look back at aquamarine Lago Pehoe, with a Nothofagus tree in the foreground:
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I saw a nice example of plumose structure in this boulder (fingertip for scale, far lower left):
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After not seeing any conglomerate since the first day of hiking, we started encountering it again, meaning that we had hiked back sufficiently to the east to re-enter the Cerro Toro formation. The conglomerate was varied, and so in one ravine, I took the opportunity to photograph its many guises...
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Nice mudstone rip-up clasts in this one:
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One final sedimentary shot for this post: another graded bed, as viewed in cross-section:
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I love graded beds. They're a key part of the geologic saga at my favorite DC-area locale (the Billy Goat Trail), and the ones in Torres del Paine were just classic: light-colored sand transitioning gradually into darker-colored mud, with a crisp boundary between each graded bed and its neighbors above and below. As noted before, these primary sedimentary structures are formed when a cascading turbidity current slows down and starts dumping its particles. The heaviest drop out first, the lightest in weight drop out last. Each graded bed = 1 turbidity current.

I've got a lot of other shots from Day 6, but I think I'll save them for a second post.

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Wednesday, January 20, 2010

Torres del Paine, day 5

On Boxing Day morn (Dec. 26), we woke at Refugio Grey, and took our camp stove outside. Just for a lark, we walked over to the shore where an iceberg had beached itself, and popped off a chunk to melt and make coffee:
cuernos_01
You haven't really had coffee until you've had coffee made with water that's been locked out of the hydrologic cycle for 14,000 years!

With warm coffee and a granola bar apiece, we walked over the small peninsula where Regugio Grey is located to the bay on the other side. There, a flotilla of icebergs had rafted up against the peninsula. We decided to spend a little bit checking them out, before heading out on the day's (short) hike to the next refugio. We had it all to ourselves:
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The icebergs varied tremendously in size, shape, color, and texture.
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So, presented with a wealth of icebergs like this, what would you do? If you answered "put one on my head!" then apparently you think the same way that we do:
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Silliness expended and coffee consumed, we grabbed our packs and hit the trail again. Today's destination was the Paine Grande Lodge. It wasn't an especially long hike, and it was essentially parallel to Lago Grey for most of the distance. Here's some more icebergs, further down the lake:
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One geological site that really caught my attention was this sweet outcrop showing gorgeously folded turbidite layers. To give a sense of scale, each of those green bushes is about 1 meter in diameter:
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Here's (white arrow) the Paine Grande Lodge, on the shore of a new lake (you can tell by the color), Lago Pehoe.
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Closer in shows the detail of this nice, modern facility:
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It was our second night indoors, and while it was a bummer that we had to share our room (6 bunks) with 4 other people, one 'up' side was that the Paine Grande took credit cards, which mean that the pisco sours were on Callan and Lily!
cuernos_07
This is the lounge, with a nice woodstove and great views of the landscape for birdwatching or just sitting back and feeling satisfied. We spend a while hanging out here, particularly as a few rain squalls moved through.

The usual routine followed: dinner, bed, dawn, coffee, hiking... on to Day 6!

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Tuesday, January 19, 2010

Torres del Paine, day 4

Christmas day in Torres del Paine National Park: We packed up our gear at Paso Campground, and hit the trail in the rain. It rained on us for about an hour as we walked south, parallel to the downstream flow of the Grey Glacier, a huge gleaming presence to our right. Occasionally, the trail exited the forest as we had to cross deep ravines, like this one:
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Snowmelt coming off the Paine Massif carved these ravines, and the park service had placed ladders in a few key locations, like this one:
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Some people didn't like the ladders very much:
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Once we got far enough along, we could see the terminus of the Grey Glacier:
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Umm, wow.

Slightly different photo composition, with a tree in the foreground:
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Nothing but terminus:
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Looking south-ish, down the axis of Lago Grey:
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Our destination for the evening was Refugio Grey, located on the far side of that first little hook-shaped peninsula.

Iceberg in Lago Grey:
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Refugio Grey:
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This was our first night spent under a roof on this trip. After three nights in a tent (me with a flat Therm-a-rest), it was quite luxurious to indulge in hot showers and a mattress! We also had a superb Christmas dinner behind those plate-glass windows, eating pork loin and drinking Gato and watching icebergs float by. It was pretty freaking cool.

That afternoon, we went for a walk down the beach, checking out the rocks. There were nice sedimentary structures and nice tectonic structures. Here's some trace fossils seen on one of the bedding planes of the turbidite strata:
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I saw a fair amount of bioturbation in the turbidites, but this was without question the best exposure I saw.

Here's a tight little anticline:
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Callan takes a nap in a little synclinal bed:
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Flame structures with palimpsest glacial striations:
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And another set, a few feet over to the right (same bed):
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There appear to be some burrows here, too (the little circles of sandstone in the mudstone below the main sandstone contact).

We slept well that night. I was especially pleased by the fact that it rained for half the night (since I was sleeping indoors).

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Monday, January 18, 2010

A very brief history of the planet Earth

Awesome! History of the Earth in 60 Seconds, a video from SEED. Perfect for Historical Geology class!

Via Geology in the West Country.

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Torres del Paine, day 3, part III

The final segment of day 3 in Torres del Paine National Park was crossing through John Gardner Pass and heading down the other side, being treated to our first view of the Grey Glacier.

Here's me huffing and puffing up the final snowfield below the pass:
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...And then we were there! This is the highest point on the Grand Circuit. An "iron woman" trail runner took our photo atop the Pass:
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The surrounding scenery spoke very clearly of recent glaciation, like these horns:
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And it was here that we first got a look at the immense Grey Glacier...
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Annotated panorama shot of the Grey Glacier:
greyday_panorama It is an impressive thing, this massive tongue of ice. Sourced in the South Patagonian Ice Field, the Grey Glacier is the largest in Torres del Paine, and effectively divides the Paine Massif from the main chain of the Andes (visible on the other side). I've noted a promontory of bedrock poking up through the ice (a "nunatak") at left, and the position of a tributary glacier at right. I was quite struck by the 'deflation' of the Grey Glacier, as marked by the disparity between the current top of the glacial ice and the line where vegetation begins.

A closer look at the tributary glacier:
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Crevasses galore, and a 'blue hole' where a stream is feeding into the base of the glacier:
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A few more shots. It's very photogenic. I don't have anything to say about these. Just enjoy:
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Peaks of the Paine massif enconced in ice and snow:
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We camped that night at Paso Campground. It was Christmas Eve, and we drank some Gato vino tinto and made a delicious fish stew for dinner. We went to bed at dark, but our campground neighbors did the European / South American thing by staying up late celebrating with one another. At midnight they sang their final song and drank their last swig of whiskey, and then there was peace and quiet... so at least half the night was silent!

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Short summary of geoblog survey results

Lutz has posted a short summary of last fall's geoblog survey results on his blog. It's in English: I'll be chewing on some of this same data in my presentation in two months at the NE/SE GSA meeting in Baltimore.

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Sunday, January 17, 2010

Fresh fodder for your mockery

I knew the Expanding-Earthers were loonies, and I'm astonished that there are still Flat-Earthers out there, but not only flat but also a square? Surely no one could hold to such an outlandish belief, right? Wrong... The Square Earthers are apparently alive and well. Astonishing.

Via Strange Maps.

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Mary Anning on Diane Rehm (or vice versa?)

Tracy Chevalier, the author of Girl With A Pearl Earring, has a new book out about the groundbreaking fossil hunter Mary Anning. She was interviewed this week on the Diane Rehm Show, an NPR-syndicated program produced a few miles from here at American University. The new book is called Remarkable Creatures.

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Saturday, January 16, 2010

Torres del Paine, day 3, part II

After our explorations of the Los Perros Glacier, its moraine, and the bedrock it has scraped so deliciously clean, we headed on up the trail, towards the highest point on Torres del Paine's Grand Circuit: Paso John Gardner. Here's a look back at the valley we've been hiking up from Refugio Dickson... Note the Los Perros moraine and the edge of the lake:
TdP3_22

First graded bed of the day. I photographed this one for the lovely scours into the underlying muddy (dark) layer:
TdP3_26

Another turbidite clast. Is that a clastic dike on the left?
TdP3_24

I thought this was really cool, too. It's a vein: a fracture filled in with a mineral deposit. I really like here how you can see little shreddy flakes of the mudrock (dark) peeling back and flexing in the fracture's void space (prior to being locked in place by mineral deposits):
TdP3_23
I interpret this to indicate that the fracture opened in a transtensional fashion, with the top to the right.

A ravine revealed this blind thrust:
mod_1

Can't see it? Here's an annotated version. The thrust fault below morphs into a fold further up:
mod_2

A sand-dominated series of graded beds:
TdP3_28

Annotated below. Some of the turbidites I saw were a meter thick!
mod_3
...and what's up with those rotty-appearing rusty spheres? (like the one left of my boot) I saw them several places... hematite concretions? (???)

Brace yourself. Here is possibly the most spectacular boulder I've ever seen:
TdP3_25

Annotated version below. This boulder shows a series of graded beds (sand = light colored; mud = dark colored). The direction of gradation shows us that the boulder is upside-down relative to original depositional orientation. A couple of small flame structures reinforce this interpretation. It has been gently folded into a broad anticline (remember, it's upside-down!) and there appear to be some small "parasitic folds" superimposed on the broader fold (at boulder-bottom; depositional-top). Additionally, the turbidites are cross-cut by a small fault which has offset the layers. If I could choose just one boulder to be airlifted from Patagonia to the front of the Science Building at NOVA, this would be the one I would choose.
mod_4

We keep hiking. We cross several snowfields and other bouldery alluvial aprons, interspersed with fingers of forest reaching up towards the hills. Looking up at the peaks, we can see turbidite layers intensely folded. Check out the straight-limbed anticline (left) and syncline (center) on this mountainside:
TdP3_21

Looking up ahead -- there at the left center (between the two peaks) is John Gardner Pass:
TdP3_17

We cross through a few more stretches of forest. This one really struck me: "Creep much?"
TdP3_20
Besides the freeze-thaw soil-shoving action of creep, I think another factor for the J-shaped (or even L-shaped) tree trunks in this forest is the thick blanket of snow they get each winter: this tamps down the whole forest in a downhill direction.

Look! On the left! Another glacier!
TdP3_19

...Shift the perspective a bit, and something else pops out. Once the hammy glacier is off-screen, you can see the wallflower in the background: A mountain composed of pink granite rather than black turbidites.
TdP3_18

We keep climbing. Higher up, another opportunity for gazing down the valley we have climbed. The Los Perros Glacier moraine and lake are readily distinguishable even from this distance:
TdP3_27

Up in the snow, we trudge higher and higher, and eventually reach the Pass. But for that, and for what we saw on the other side... I'm going to make you wait for Part III.

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Friday, January 15, 2010

Torres del Paine, day 3, part I

Day 3 of our backpacking tour in Torres del Paine National Park (Chile) was an especially rich one. There's so much material to share that I'm going to divide the day up into three chunks: (I) the area around Los Perros Glacier, (II) the area on the east side of John Gardner Pass, and (III) the area west of John Gardner Pass, including the Grey Glacier.

We begin in Los Perros. As you will recall from our last installment, Lily and I had put in a long day of hiking, essentially pulling double duty by hiking all the way from Seron to Los Perros, and skipping Dickson in between. Because the park only allows camping in certain designated areas, trekkers are often put in the position of either hiking less than they want on a certain day, or more than they want. Day 2 was more than we wanted. We slept heavily, and woke to a drier world. We made coffee (we tried out those new Starbucks "Via" instant coffee packets on this trip and found them reasonably acceptable) and decided that before the day's slog, we should backtrack a bit to the Los Perros Glacier and check it out in more detail. As we were hiking in to camp the previous evening, we only had a 5 minute window of decent weather to view the glacier and its surroundings, so we wanted to see what we had missed.

It was a good call. I really enjoyed poking around there. To start with, check out this perspective view down the valley we had hiked up the previous day, the horseshoe-shaped glacial moraine, and the gray-colored glacial lake backed up behind the moraine:
TdP3_03

A closer look at the till making up the moraine:
TdP3_01

...And in another direction, too:
TdP3_02

Composite stitched together of the moraine-dammed lake, using both of the previous two photos plus three others:
los_perros_panorama

Looking down the axis of the lateral part of the moraine (perspective is towards the glacier, though the ice itself is hidden by the bedrock ridge):
TdP3_04

"Lil on till":
TdP3_16

We walked towards the glacier, checking out the accumulation of icebergs up against the moraine:
TdP3_06

A closer look at the terminus of the glacier:
TdP3_10

It was a cool place to look at rocks, too. Everything was so fresh, since the glacier had so recently scraped them clean. In this photo, looking across the lake, you can see the line where the vegetation abruptly stops, showing where the glacier was until relatively recently, when it receded to its present position.
TdP3_12
A little lateral moraine clings to the walls of the valley. Where it has been eroded away, you can see details of the bedrock, like the granite dike visible on the left.

If you look carefully in this photo, you will see a large vertical granite dike. Follow along in the direction I am pointing. Hopefully you will be able to find it:
TdP3_09

This dike continued out into the space where the glacier eventually carved the valley where the lake now sits. But in the middle of the lake is an island, and right along strike from the big granite dike, you can see a granite dike cutting across the rock of the island:
TdP3_15
I'll bet it's the same one.

These dikes had some cool details revealed in the area around Los Perros Glacier. Here's an explosion of dark xenoliths in one intrusion. This is clearly intrusive, because it cuts across several turbidite layers, but I was confused about the texture. I expected granite, but it really looked kind of like... sandstone.
TdP3_07
I know there are some clastic dikes in the area, and this may be one of them. I've never seen clastic dikes before, but I guess this is what I would imagine they would look like.

...and how about this???
TdP3_08
I think that's two clastic dikes cross-cutting a turbidite bed. A nice relative dating exercise, eh?

Some Z-folds reconfigure quartz-filled tension gashes:
TdP3_11

I also found a cool little chunk which showed a nice set of concentric ribs:
TdP3_05

Classic slickenlines, lacking those gaudy crystal fiber lineations you usually see on fault surfaces. This is gouging, pure and unadulterated and simple:
TdP3_13

Such geological goodies! It's better than instant coffee for perking a fellow up in the morning hours. Energized and invigorated, we headed back to Los Perros Camp for our packs, and hit the trail, heading further up the valley. More on that in part II!

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Thursday, January 14, 2010

Call for Judges

Call for Judges for the Undergraduate and Graduate Student Poster Competitions at the 2010 Joint Northeastern/Southeastern Sections Meeting of the Geological Society of America.

Are you interested in helping support the careers of young geoscientists? Then consider volunteering as a judge for the undergraduate and graduate student posters at the 2010 Joint Northeastern-Southeastern Section Meeting of the Geological Society of America.

All student poster presenters from both the Northeastern and Southeastern Sections will be considered in the competitions. The response to the call for abstracts for the meeting has been extremely positive, and we anticipate judging a large number of presentations. Your help is needed to make this a success! Judges will be assigned no more than eight posters to evaluate, and they will be provided with an evaluation form to streamline the evaluation process.

If you are interested in being a judge, please respond to one of the members of the Poster Judging Committee listed below. You can contact us anytime between now and the meeting, but the sooner you contact us the better as this will make organizing the judging more efficient.

We will contact volunteers in early 2010 after the technical program is finalized to find out which day(s) volunteers are available to judge and which discipline(s) volunteers are interested in judging.

Thanks very much for considering this request. We look forward to hearing from you.

Jean Crespi
University of Connecticut
jean.crespi@uconn.edu

Helen Mango
Castleton State College
helen.mango@castleton.edu

Callan Bentley
Northern Virginia Community College
cbentley@nvcc.edu

Jean Self-Trail
US Geological Survey
jstrail@usgs.gov

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"Green Guilt" essay: carbon anxiety follow-up

"Green Guilt," an article in the Chronicle Review by Stephen T. Asma, offers a nice follow-up to my earlier examinations of my own travel-induced carbon anxiety.

Via Idea of the Day.

...Also, on that same topic, it occurred to me that I should share this quote by my favorite author, Edward Abbey (emphasis is mine):
"One final paragraph of advice: Do not burn yourself out. Be as I am-a
reluctant enthusiast... a part time crusader, a half-hearted
fanatic
. Save the other half of yourselves and your lives for pleasure
and adventure. It is not enough to fight for the land; it is even more
important to enjoy it.
While you can. While it is still there. So get
out there and mess around with your friends, ramble out yonder and explore the
forests, encounter the grizz, climb the mountains. Run the rivers, breathe deep
of that yet sweet and lucid air, sit quietly for a while and contemplate the
precious stillness, that lovely, mysterious and awesome space. Enjoy yourselves,
keep your brain in your head and your head firmly attached to your body, the
body active and alive, and I promise you this much: I promise you this one sweet
victory over our enemies, over those deskbound people with their hearts in a
safe deposit box and their eyes hypnotized by desk calculators. I promise you
this: you will outlive the bastards."

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Torres del Paine, day 2

Rested up from Day 1 in Torres del Paine, we were pleased to see that day 2 dawned bright and sunny.

Lily takes a morning break to shed layers:
TdP11
The weather in Patagonia was really variable, as was the trail. This meant that all day long, we were stopping to put on layers or take off layers as we got cold or hot. It was kind of a pain. Whine whine whine.

All day, clouds scudded along, but we didn't get any rain until late in the day. The main part of the Paine massif was coming into view. Here's a shot from noon-ish:
TdP13

Here's a shocker: ...We saw more rocks!

Here's another graded bed:
TdP19

And a little plumose structure, showing a nice twisty hackle fringe:
Plumose 1

When I first saw this outcrop, my brain's pattern-recognition center peeped: "CRINOID STEMS!"
TdP05
...But upon closer examination, they lacked pentameral symmetry, and were some were kind of lumpy. And considering the main rock here is Cretaceous-aged, crinoids could be present, but they aren't as likely a candidate for fossilization as they would have been if these rocks were Paleozoic. So I think these were concretions of some kind. Chert? I shared this image with Patagonia geology expert Brian Romans, and he pointed out something I hadn't noticed in this image: the flame structure in the lower left. That indicates this boulder is upside-down, relative to its original depositional position.

Here's another concentrically-zoned jobbie, which I interpret as a concretion. Overall, this thing was like a pig-in-a-blanket, but on steroids:
TdP16
I think it's a flint nodule. Brian hasn't seen any crinoids or any concretions in these rocks, so I'm at a loss to offer further explanation.

I was flummoxed by this one, too:
TdP14
This time, the pattern-recognition center wanted it to be a trilobite, but that's impossible (or, strictly speaking, not impossible but history-re-writing-able) in these aged rocks. Brian tells me it's almost certainly an inoceramid bivalve. That works for me.
(...Or could it be... pseudosegments???)

We walked on, through fields of little white flowers:
TdP15

Angling towards the main massif, more gnarly peaks came into view...
TdP18

One thing you can see well in this shot is the contrast between the color of the darker Cretaceous-aged sedimentary host rocks (turbidites) and the light-pink-colored granite which intruded them around 12 million years ago (Miocene).
TdP17

A bit further on, we could get a decent look at the intrusive relations (through binoculars):
TdP22
(In this annotated photo, "T" is for "turbidite," "Gr" is for "granite.")

We dropped down off a moraine towards Refugio Dickson, where we made tea, rested a bit, and pushed on again...
TdP20

At the head of Lago Dickson was an impressive looking glacier, dropped down out of the South Patagonian Ice Field and into the lake:
TdP21

It was around 1pm when we got to Dickson. We were tired, but the day was only half over. We decided to push on, and essentially do two days' hiking in one. Next stop: Refugio Los Perros!

We hiked on through PRIME Magellanic woodpecker habitat, and it just KILLS me that I didn't see one there, though I did see a few other new birds. Then the rain started, and we started to get tired. But we were committed at this point... We pushed on, and on, and on, and on, climbing up through a forested valley, until finally we popped out on fresh glacial moraine, and saw this:
Perros01
That's the Los Perros Glacier! A short distance further up the valley was the campground. At this point, the rain had morphed into snow, blasting us in the face as we slogged along, really looking forward to dinner and sleep. Maybe not in that precise order. Eventually, we got there.

Fortunately, the clouds parted for literally 5 minutes, and we were able to have our portrait taken by a doctor from Santiago, who was hiking there for Christmas with his family. They were literally the only Chileans we met who were in the park as tourists (i.e., not park employees or concessionaires) our entire trip. I think we look happy to be in such a special place, don't you?
Perros02

Next up: Day 3, when we cross John Gardner Pass and see the Grey Glacier for the first time!

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Wednesday, January 13, 2010

NE/SE GSA program released

Turns out I'm going to be co-chairing the session in which I'm presenting.

Here's my abstract:
Web-logs (or "blogs") specializing in the geosciences have been increasing
in number and diversity over the past three years. These geoblogs have blossomed
into an important online resource for the interested public, as well as a
positive online community that spans every continent and most subdisciplines of
geology. This novel medium for communicating geoscience has both promise and
potential for problems. In late 2009, geobloggers were surveyed in an attempt to
provide a snapshot of the state of the geoblogosphere. Data from this survey
will be presented here, introducing a representative sample of geoblogs, growth
patterns, geobloggers' motivations, as assessment of how this new medium is
doing, and correlations with usage of other "Web 2.0" applications.

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15 GSW Presidents in one room

GSW_Pres
Presidents past (and one future) gathered for dinner in the Cosmos Club before the Presidential address of Bill Burton, hours before he joined their ranks. From left: incoming president Jay Kaufman, John Slack, Dave Stewart, Peter Lyttle, Jane Hammarstrom, Rich Walker, Roz Helz, George Helz, about-to-be-past president Burton, Dave Applegate, Doug Rankin, Nick Woodward, Doug Rumble, Dick Fiske, and Brooks Hanson. Photo by Mary Horan. Make bigger by clicking here.

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Contest answer: Glaciation analogy

Yesterday, I asked you to figure out what I was getting at here:
BLANK

The answer is that I was trying to depict the fundamental difference between the two different classes of glacial landforms by showing the two different actions glaciers can take on rock: either they can carve it up, or they can carry it off a ways and dump it.
block carving

Glacial landforms may be broadly grouped into erosional landforms (like cirques, aretes, horns, and hanging valleys) and depositional landforms (such as moraines, eskers, drumlins, and kettles). Erosional landforms dominate in areas of alpine glaciation (like, say, the Patagonian Andes). Depositional landforms dominate in areas of continental glaciation (like, say, Wisconsin).

If any educators want a full-size (i.e. PowerPoint-ready) version of this image, shoot me an e-mail. I'll send you one, and I won't do so at a glacial pace.

Nobody really guessed it. But there were some great guesses regardless, and perhaps the big lesson is that the Analogy Is In The Eye Of The Beholder. Thanks to all who contributed ideas to the discussion!

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Tuesday, January 12, 2010

Contest: Guess the analogy

Okay... on Monday I made up this image to illustrate an important concept in my Physical Geology class. Can you figure out what it is, specifically?
BLANK

Leave your guesses in the comments section. First one to get it right wins a GEOLOGY ROCKS bumper sticker or some choice NOVA swag! (Your choice)

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AMS Climate Change Adaptation briefing

Last Friday, I went to a briefing in the Cannon House Office Building on Capitol Hill about adaptation to climate change. I present here a transcription of my notes as a quick, unpolished rundown of what was discussed there. It may be of interest to you.

The speakers, their titles, and their topics were:
  • Michael MacCracken, Chief Scientist for Climate Change Programs, the Climate Institute: Projected impacts of Climate Change on the United States

  • Kristie L. Ebi, Executive Director, Intergovernmental Panel on Climate Change (IPCC) Working Group 2 Technical Support Unit - Impacts, Adaptation, and Vulnerability: Adaptation

  • Katharine L. Jacobs, Professor, University of Arizona Soil, Water and Environmental Science Department: Adaptation to water resource changes

  • Susanne Moser, Director and Principal Researcher, Susanne Moser Research & Consulting: California as a case-study in adaptation planning
MacCracken was first up, and gave [what I was surely biased to percieve as] the most compelling talk. I felt this way not because he was the only dude, but because he was talking science, while everyone else was talking adaptation -- how humans should/can/might respond to climate change -- a topic I find fundamentally less interesting than the science. However, I'm teaching environmental geology again this semester, and having some clue as to policy options is a part of my job. That's why I went. Citing the IPCC and a UNEP report (reproduced above because I think its cover design is pretty clever), MacCracken informed us that the overall projections for North America is that it will get wetter in the north and drier in the south. He noted that there is less confidence in precipitation projections than there is in temperature projections. Water is going to be one of the most important aspects of climate change, MacCracken asserted. Tangentially, he also suggested that the large amount of snow we're seeing in the U.S. this winter has to do with less ice cover on the Great Lakes (encouraging evaporation and precipitaiton as snow). He showed a cool graph of corn yields over time, showing the crop's susceptibility to extreme climate events (superimposed on an overall upward trend). I found this to be interesting, and coveted the graph. [Eventually, all the speakers' PowerPoints will be available at the AMS Climate Briefing site - but they are not there yet.] He showed some good graphs showing projections of sea level rise under high, medium, and low emissions scenarios. He also cited Isabella Velicogna (2009), displaying graphs which show estimates of ice mass loss from Greenland and Antarctica. (I need to get a copy of these images: very compelling! The Way Things Break discussed them in October, when they were first published.) Finally, he brought up ecosystem changes, showing us maps of the spruce bark beetle infestation on the Kenai Peninsula of Alaska (a forest catastrophe I have seen firsthand).

Ebi spoke quietly about adaptation in general. Adaptation is in contrast to mitigation, which is what most people spend their climate time talking about: Mitigation attempts to prevent future climate change (by limiting emissions of CO2 or by capturing CO2 and sequestering it), while adaptation says, "given a certain level of climate change, what do we do in order to maximize human welfare?") She noted that the impacts we face are entirely contingent upon which adaptation strategies we adopt: a given quantum of climate change will have different effects upon identical communities which adopt different levels of adaptation. Ergo, adaptation is important, and we really need to start talking about it. She made the claim that the federal Stimulus package was a major missed opportunity, as major infrastructural investment was made without consideration as to whether long-term infrastructure should be modified or moved. For instance, before rebuilding a bridge, perhaps we should be asking ourselves if it should be taller, or before repaving a coastal road, we should perhaps consider moving it to a higher elevation where it is likely to last longer. She gave a compelling example of Barbados (I think), where coastal mapping showed that with year 2100 projections for sea-level rise plus a category-3 hurricane, the portion of Barbados' coast to be flooded will include both the power plant and the coastal road! While Barbados has been proactive in addressing these issues, Ebi says the U.S. has not. Adaptation, she argued, is nothing more than iterative risk management. She gave a list of criteria necessary for action, and you can see that the U.S. is falling short of the minimum threshold for action on many of them:
  • an awareness of the problem
  • an understanding of the causes
  • a sense that the problem matters
  • a capability to influence outcomes
  • political will to deal with the problem
The third expert to speak was Kathy Jacobs. She pointed out that many of the projected impacts of climate change will be delivered, one way or another, via the water cycle. One example she gave that caught my attention was the declining amount of snowpack in the western U.S. Historically, this snowpack has been a fundamental reservoir of water during the summer months, and as it melts away, we are going to need to build artificial reservoirs to compensate. She noted that this sort of adaptation is uniquely human: ecosystems do not have the foresight or ability to build reservoirs and the like -- so if we want those ecosystems to continue to function, we will have to do their planning, too. She discussed the Colorado River, which is estimated to decline somewhere between 11% and 40% at the same time demand for its water is increasing. She said, "We may not know the magnitude or the rate of change [in Colorado River discharge], but we know the direction of change" (i.e., downward). The comment she made that impressed me the most was that the current uncertainty (in U.S. society) about whether climate change is real is blocking action. She was citing the frequently-made argument that because we don't understand everything about climate change, we shouldn't take any action. "Yet we make decisions with imperfect information all the time," she said. "Climate change shouldn't be any different. We need to get past that." She made two final points: (1) that there is no silver bullet solution to our burgeoning water resources crisis ["We will need a broad portfolio approach" including things like desalination], and (2) Many of the current water technologies are energy intensive, and these technologies will be less attractive in the future because of their carbon cost.

Susanne Moser was the last one at bat. She detailed California's response to the question of adaptation. It was an interesting case study, because under the leadership of Governor Schwarzenegger, an office was formed to examine what adaptation might mean for the Golden State. This office provides bi-annual updates to the government of California on the state of the science. They are the only state to do this, so far (though ~a dozen other states have taken less decisive measures). Unfortunately, "California is also adapting to bankruptcy," and so really this golden example of adaptation is hamstrung by economic constraints: It is really only a baby step.

I enjoyed the briefing. It was the sixth or seventh AMS-sponsored briefing I've attended on Capitol Hill, and it was informative as always. Typing up these notes reminds me how useful it was. I'd like to thank AMS for making these sessions open to the general public, and for providing lunch to all the participants.

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Monday, January 11, 2010

Climate change exhibit at AAAS

Local yokels! Head on over to the American Association for the Advancement of Science at Metro Center for their new climate change photo exhibit.

Hat tip to Surprising Science.

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Visual evidence of hypocrisy

Remember how I was lamenting the carbon footprint of my globetrotting?

Here's a nice summary of that issue in an image:
IMG_2291
Smoke from the engines of the M.V. Evangelistas drifts across the terminus of the largest valley glacier in South America.

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Tree Lobsters: Skeptics and Charlatans

Torres del Paine, day 1

From Puerto Natales, we took a bus with other backpackery types north to Torres del Paine National Park, the main object of our trip. It was a bit rainy when we left the bus and walked off into the park, aiming to complete the Grand Circuit, a 7-day, 100-km hike around the Paine Massif. Heading down the trail:
TdP04

Google Map of the Paine Massif, the main focus of the national park:

It's a little offshoot of the main Andean cordillera, a relatively isolated block of mountains rising from the Patagonian steppe. The park is named for some towers ("torres" in Spanish) in the eastern part of the massif. The word "paine" ("pie-nay") apparently means "light blue" in the pre-Spanish native language. This is apparently because many of the lakes (so prominent in these maps) are light blue in color due to the large influx of suspended glacial "milk."

Here's the specific route we took (approximately) in blue:

We hiked in a counter-clockwise direction.

So we started off over in the eastern part of the park, headed north by northwest. We were hiking through steppe, with the snow-covered mountains rising to the west:
TdP02

...But wait, what's that on the horizon?
TdP03
Guanacos! These are camellids -- related to the better-known llamas of Peru.

Thumbs-up for guanacos!
TdP01

The rocks of Torres del Paine are mainly Cretaceous-aged turbidites (shale, graywacke, and conglomerate), intruded by granitic magma in the Eocene. All along the whole trip, I was drooling over the many beautiful graded beds I saw. Here's the first photogenic graded bed I found, with the paleo-top of the bed at the top of the photograph:
TdP06

These rocks of the Cerro Toro Formation were deposited in the Magallanes Basin, a Cretaceous to Paleogene retroarc foreland basin. Brian Romans of Clastic Detritus shared some information with me before I went down to Patagonia, and I am indebted to him for the insights I gleaned from that sharing. However, any errors in identification or interpretation are my own. According to the model of Romans, et al. (2009)*, a fold and thrust belt was operating to the west, and an elongate north-south oriented submarine trough flexed downward east of that during the Cretaceous. Mud and sand and gravel flowed into this sedimentary basin mainly from the north in three phases which can be contrasted readily with one another in terms of depositional style and confinement of depositional area. These three phases of deposition correlate to different facies, and are exposed well in the area north of Puerto Natales due to subsequent deformation and uplift (not to mention recent deglaciation).

I'm a structural geologist, and deformation is what I am all about, but I honestly didn't expect to see much structure when in Torres del Paine. (I was eagerly anticipating the graded bedding, though!) So it was somewhat shocking to see some very deformed turbidites on that first day of hiking. Here's me standing on the edge of the Paine River, surrounded by tilted turbidite strata:
TdP07

...And this stuff was really messed up:
TdP08

Zoomed-in, you can see some severe folding and faulting having shuffled up these rocks:
TdP09

We hiked about six or seven miles that first day, and camped at a place called Seron. The park has set up these dozen or so campgrounds where you are allowed legally to camp. Some are free, some cost a few bucks. Seron cost about $8 per person to camp there, but we got hot showers with that cost: Nice! The sun set on our first day, and we slept well.
TdP10

More soon, on our second day of hiking...
____________________________________________
* Romans, B.W., Fildani, A., and Hubbard, S.M., 2009. "Controls on Deep-Water Stratigraphic Architecture," in Stratigraphic Evolution of Deep-Water Architecture: Examples of controls and depositional styles from the Magallanes Basin, southern Chile, SEPM Field Guide No. 10, p. 7.

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Sunday, January 10, 2010

Pseudosegments

One of the things we try and impart to Historical Geology students at NOVA is that not everything that looks like a fossil is necessarily a fossil. For instance, we talk about concretions and dendrites as being inorganic forms that might look organic to the untrained eye.

I think I've got a new one, though.

Check this out:
pseudopsegments

That's a mineral deposit left at the bottom of my Pyrex brownie-baking tray after washing it in the (relatively "hard") water at my house. The drying water blob contracted in a series of dessicating pulses, leaving little rims which strongly resemble the segments in the body plans of many organisms including annelid worms, arthropods, Pikaia, and what-not. I hereby dub these "pseudosegments," though I am unaware of them actually being found anywhere in the geologic record. They are inorganic, but might catch one's eye as being similar to the segmentation seen in many living critters. Also, I am tempted to spell the name as "pseudopsegments."

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Netflix rental map (NY Times)

Check out this interesting interactive map in today's Times - showing rental patterns from Netlfix.

To get a glimpse of the sociology of the DC area, compare the DC maps for "Milk" and "Paul Blart: Mall Cop." Wow.

Hat tip to Lily.

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Saturday, January 9, 2010

Carbon sequestration in basalt

A video by the crew at NPR's Science Friday. Worth watching, even if you grit your teeth at the conflation of "calcite" and "limestone."

Hat tip to Bob L'Hommedieu

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Puerto Natales, Chile

Here's a few shots in and around Puerto Natales, Chile, the point of our disembarkation from the M.V. Evangelistas (Navimag ferry).

Arriving in port:
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On the waterfront, we see Black-necked swans (!!) with some Chiloe widgeon:
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While I was looking up the duck in my field guide, a mylodon (giant ground sloth) snuck up behind me:
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...Just kidding. It's a statue, not a real mylodon. They went extinct along with the rest of the Pleistocene megafauna. There's a cave near Puerto Natales where mylodon remains have been found. A scrap of hairy skin made its way to the home of Bruce Chatwin, inspriring him to eventually travel to Patagonia and write the classic book In Patagonia as a result. This book was a fundamental source of inspiration for me to travel to the region. I re-read it during my trip there this winter, and so I was pleased to see Mr. Mylodon.
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Puerto Natales has capitalized on the mylodon. All the street signs have a little silhouette of him rearing up. At the statue, Lily pulled on his tail:
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The foundation for the mylodon statue had a lot of interesting rocks incorporated into it. By the ground sloth's left foot, there was a nice collection of spherical concretions:
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Aside from birdwatching and mylodon-harassment, we spent the afternoon organizing our gear and buying food for our backpacking trip. From Puerto Natales, we took a bus up to Torres del Paine National Park...

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Friday, January 8, 2010

I'm on a boat

OK, time to start showing some photos from this winter's trip down to Patagonia. Today, I'll talk about our journey south from Puerto Montt, Chile, to Puerto Natales, Chile. We took a ferry, the M.V. Evangelistas, operated by Navigaciones Magallanes, better known as Navimag. We flew through Santiago, and had to spend a couple hours laying over in that airport. During that time, we checked out this tower of luggage that had been set up in an otherwise-unused space:

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Black-fronted ibis (see full bird list here) in Puerto Montt:
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The Evangelistas in port, prior to our departure:
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Steaming out of Puerto Montt, we got good looks at two volcanoes. The smooth white one on the left (north) is Volcan Osorno, and the craggier one on the right (south) is Calbuco:
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Heavy cloud cover prevented us from seeing Chaiten the next day, which was a bummer considering all the press it got for its eruption in 2008.

A few shots to show the scenery typical of the next three days as we sailed south towards Puerto Natales:
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A ship that ran aground in the 1960s:
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We passed a lot of the time in birdwatching. Peering over the deck with binoculars pressed to your eyesockets is a good way to attract other birders. So we made friends with Rory and Leann, a South African couple on a month-long tour of South America. That's Rory in the red jacket:
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Doing this, I saw my first penguin, dozens (hundreds?) of albatrosses, and the flightless steamer duck, which is, as Rory enthusiastically pointed out, "a f#%king flightless duck!"
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When I see a new species, I note the date and location in my bird guide:
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One day, we made a detour to go check out the "Pio XI" or Bruggen Glacier draining into the ocean from the South Patagonian Ice Field (fourth largest ice sheet in the world, after Antarctica, Greenland, and the Elias-Kluane ice field in Alaska and Canada). The Bruggen Glacier is the longest in the southern hemisphere, outside of Antarctica. It is the largest glacier in South America. And it is named for a Chilean geologist!
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Here's a satellite view of the area, courtesy of NASA's Earth Observatory:

On the way over to the glacier, we saw the first iceberg of the trip:
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Note all the sediment in that ice: it's dirty stuff!

Getting closer:
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Closer still, and a medial moraine becomes visible as a dirty stripe running through the middle of the glacier:
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Happy tourists:
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Continuing south, we encountered more and more islands, and in many places the channel through which the Evangelistas sailed was quite narrow.
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At one point, we squeezed through this NARROW gap:
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Finally, we approached Puerto Natales, a small town that serves as the main access point for Torres del Paine National Park:
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Looking in the opposite direction, I was pleased to see a broad syncline screaming out from the mountainside:
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More on Puerto Natales this weekend...

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Wednesday, January 6, 2010

PSW on bioturbation

PALEONTOLOGICAL SOCIETY OF WASHINGTON
presents

Bioturbation and Sedimentation in the Devonian World of Oklahoma
by Erik P. Kvale
Senior Geologist, Exploration-Central, Devon Energy Corporation

Wednesday, Jan. 20, 2010
7:00 p.m., in the Cooper Room, National Museum of Natural History
10th St. and Constitution Ave.
Non-Smithsonian visitors will be escorted
to the Cooper Room at 6:30 and 6:55 p.m. Meet in the Constitution Avenue lobby at 5:00 p.m. to join us for dinner at 'Elephant and Castle.' Latecomers can meet directly at the restaurant at the NW corner of 12th & Penn. Ave., NW

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Tuesday, January 5, 2010

Gravity wells, illustrated

Monday, January 4, 2010

Climate Adaptation Briefing on Capitol Hill

Bird list - Patagonia 2009-2010

I'm a birder. Birds were my first professional interest, before getting turned to the Dark Geology Side. I still carry my binoculars on most of my trips, and have a shelf full of bird field guides from dozens of regions of the world. Chile was a lot of fun for me, birding-wise. The ferry trip from Puerto Montt to Puerto Natales gave me access to dozens of pelagic bird species I've never seen before, including hundreds of albatrosses. As a birder, you have to love a country that has both flamingoes and penguins! Chile also isn't overwhelming in terms of huge numbers of bird species (unlike, say, biodiverse Ecuador). It was pretty easy to see a significant number of the native species in two weeks. However, I confirmed a couple of these with better looks subsequently, during my brief time (4 days) in Argentina. Here's my list of identified birds for the whole trip:

Silvery grebe
Royal (or maybe Wandering?) albatross
Northern giant-petrel
Black-browed albatross
Sooty shearwater
Magellanic penguin (my first wild penguin!)
Peruvian pelican
Red-legged cormorant
Neotropic cormorant
Rock cormorant
Imperial cormorant
Darwin's rhea (my first wild rhea!)
Great egret
Black-crowned night heron
Black-faced ibis
Chilean flamingo
Black-necked swan
Coscoroba swan
Kelp goose
Upland goose
Flightless steamer-duck (one of the world's five species of flightless duck)
Crested duck
Yellow pintail
Chiloe widgeon
Red shoveller
Andean (ruddy) duck
Turkey vulture
Black vulture
Andean condor
Black-chested buzzard-eagle
Cinereous harrier
Southern caracara
Chimango caracara
American kestrel
White-winged coot
Red-gartered coot
Red-fronted coot
Southern lapwing
Magellanic oystercatcher
South American snipe
Parasitic jaeger
Chilean skua
Kelp gull
Dolphin gull
Brown-hooded gull
South American tern
Rock dove
Eared dove
Austral parakeet (WTF? A parakeet next to a glacier? I love Chile!)
Chilean flicker (sadly, I did not manage to see the Magellanic woodpecker, and that makes me quote sad. I think I'll have to go back...)
White-throated treerunner
Thorn-tailed rayodito
Magellanic tapaculo
Dark-faced ground-tyrant
Spectacled tyrant
Austral negrito
Fire-eyed diucon
White-crested eleania
Tufted tit-tyrant (yes, really!)
Rufous-tailed plantcutter
Austral thrush
Austral blackbird
Yellow-winged blackbird
Long-tailed meadowlark
Patagonian sierra-finch
Mourning sierra-finch
Rufous-collared sparrow
Black-chinned siskin

...That's 69 species of birds, mostly brand new to me. Plus there were a bunch in Buenos Aires that I have no idea about... Oh well.

While I'm at this listing business, here's a list of wild mammals I saw:
Guanaco (a llama-like camelid)
Bottlenosed dolphin
Sea lions (sp?)

...Significantly shorter list, eh? That's why people go into birding so obsessively... and why you never hear about anyone going "mammaling."

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Sunday, January 3, 2010

First photo from Patagonia

Just got back to DC, and I'm pleased to report that I had a great trip. I hope you enjoyed the posts I set to publish automatically in my absence --- just like I was never gone! You'll be hearing much more about my time in Patagonia in the days to come... ...but for now, here's one image to whet your appetite:
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Friday, January 1, 2010

Words' worth III

Happy new years! The grammar police return! A while back (May!), I commented on a few words that had gotten my attention through their misuse. Since then, a few more peaked piqued my interest, and now I return with the third installment of "Words' worth."

Peak / Peek / Pique - "Peak" means summit or maximum value; "Peek" means look at quickly or furtively; "Pique" means provoke or stimulate. You can "take a peek," but you cannot "take a peak" (unless you're involved in Appalachian coal mining). You can have something "pique your interest," but you cannot "peak your interest" in anything.

(Similiarly): Eke / Eek - People can "eke out a living" but they should reserve "eek" for unexpected encounters with mice.

Cite vs. site - a "site" is a place, either in the real world or on the web. You use "cite" when you're attributing work to someone else (or issuing a ticket, if you're a traffic cop).

Extinction vs. extirpation: extinction of a species or variety means there are none left, anywhere. However, the local version of the phenomenon is properly known as extirpation. Thus, if say you killed every single wallaby in Australia, but the wallabies on New Guinea were still numerous, you would have extirpated them from Australia, but you would not have made them extinct. Even professionals use "extinction" where they ought to be saying "extirpation."

Similarly, a lot of people use the word decimate "incorrectly." To decimate a population (say, of Roman soldiers) was to kill one out of every ten. 10% die, in other words, and 90% are left alive. That may be the official definition, but the truth of the matter is that the vast majority of people use the term decimate in exactly the opposite sense: that 90% die, and only 10% survive (or thereabouts). At what point do we switch the definition of a word: when 90% understand the meaning to be one thing, and only 10% stick with the old definition?

Shear vs. Sheer - There are many definitions to both "shear" and "sheer," but the one I see fuddled up most frequently is when people use "shear" to describe cliffs, or use "sheer" to describe geological stresses.

Oh dear: did you hear about the omission of "emission" on a Kansas state test (wherein some test-writer swapped the word omission for emission). Don't worry: the kids caught the error!

Literally - "Literally" means "actual," not an exaggeration, analogy, simile, or hyperbole, but actual truth. Amazing how many people use this incorrectly. Sometimes it seems like literally the entire world!

Metamorphosize - The first time I put up a post like this (see link above), I harped on the word "orientate." I pointed out that the word "orient" (verb) means the same thing, without an extra, unneccesary syllable. In spite of my harangue, orientate remains in the dictionary. Even worse, I find a lot of people want to throw an extra syllable in at the end of "metamorphose" even though "metamorphosize" is not an actual word.

Standing on line versus standing in line. This one seems to be cultural. Some people claim that when you queue up for, say, a movie, you're standing "on line." This grates on my ears, and I would instead say that you're standing "in line." (I reserve "online" for internet presence.) But I don't know that I am justified in feeling this way -- I think it's more likely that I just grew up in an "in" household, versus an "on" household.

As before, I'd like to know which words bug you. Chime in.

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