Volcanoes past and present

The lake district is in the northwestern part of Patagonia, where the landscape has changed somewhat. In Argentina, the lakes are still on the dry side of the Andes, but the country border here jogs a little westward to capture more of the cordillera with its mountains and green forests. The nothofagus is still here—southern beech tree that evolved when the continents were together in Gondwana—but there are also abundant conifers. The towns of Bariloche and San Martín de Los Andes are the two main jumping-off points to explore this region.

The geology has changed too. If you look at the map in the 12 February posting—tectonic plates at the end of the world—you will see that the oceanic plates on the west side of South America change along the length of Patagonia. In the south (Austral Andes) the Antarctica plate is subducting at a rate of only 1–2 cm/year and there are a few scattered volcanoes that are not prominent features of the landscape. Farther north (around 46–49 degrees latitude) there is a volcanic gap where the Chile Rise (mid-ocean spreading ridge) is being subducted beneath South America. But here in the lake district (north of 49 degrees) we are now in a classic Andean volcanic area, where the Nazca plate is being subducted beneath South America at a rate of about 7 cm/yr and producing a chain of stratovolcanoes that evoke the conical shapes of Mount Fuji or Mount Shasta.

The currently active volcanoes are on the west side of the cordillera, in Chile, where volcanoes like Villarica are among the most active in all of the Andes. But, being in the zone of the westerly winds, Argentina receives much of their ash. Most recently, on 4 June 2011, Puyehue volcano erupted suddenly and spewed ash that covered Bariloche, San Martín, and the surrounding area with up to 0.5 meter (1–2 feet) of whitish, silica-rich ash that disrupted daily activities and closed airports throughout the northern part of Patagonia.

Much of the landscape between Bariloche and San Martín appears to be dusted with snow. All of the slopes in this photo are white because of their coating of ash.

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Yesterday we traveled on a road that runs east–west directly west of Puyehue volcano. Even 9 months later, the effects of the ash were quite evident. A sign at the start of the road warned us of possible low visibility due to the ash (ceniza).

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Along the river were large quantities of ash that had been formed into rippled bedforms, and the water was a whitish beige color from the ash it was carrying away from the surrounding slopes. In the background, the exposed bedrock is volcanic rock from a much older episode of active volcanism in the region. If you like volcanoes, this is a very good place to visit!

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One thing that hasn’t changed from the south is a landscape that has been recently scoured by glaciers. The lakes are long, narrow “finger lakes” that were carved by ice and that are bounded by glacial deposits such as moraines.

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Here, though, we are north of the Patagonian ice field and the ice forms only isolated glaciers. Even near the peaks, many of the glaciers have been completely melted, leaving behind the classic landscape of knife-edge ridges and elevated cirques.

The region is rich in national parks, the most popular of which is Parque Nacional Nahuel Huapi. Bariloche is at its edge and unfortunately has suffered from overdevelopment as a result. A redeeming feature, however, is the ability to take local buses to the park, where day hikes or multi-day backpacking trips can be made. The local alpine club (Club Andino) operates a series of refugios (mountain huts) that offer basic lodging and food. We did a day hike to Refugio Frey, at the base of Cerro Catedral. Like our Cathedral Peak, in the Sierra Nevada, this peak is made of Cretaceous granite that cooled deep in the earth, in this case when the magmatic arc (chain of active volcanoes) was located east of its current position.

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A glacial erratic (large boulder dropped from ice) along the path has provided the roof for another, much smaller, refugio!

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Another redeeming aspect of Bariloche was its celebration, on 28 February 2012, of the 200th anniversary of the national flag. In the main plaza, a military band played while a group of men and women danced. In the background is an example of the buildings in the Centro Civico (civic center). They are made of a distinctive green volcanic rock and local wood. Unfortunately, much of this charming architectural style has been replaced by less attractive modern structures.

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Still, one can’t feel too badly about a place that is just a short bus ride from a national park with beautiful sedimentary rocks filled with angular metamorphic clastic (prominently displayed in photo below), abundant evidence of ancient and active volcanoes, and, of course, glacially-scoured landscapes!

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La Ruta 40—now and 9,000 years ago

You may be familiar with Highway 50 in Nevada—it is the slow road going east–west. A book about this road is titled “The Loneliest Road in America”. It gives a mile by mile description of features along the way (ghost towns, sand dunes, gold mines, etc.). For La Ruta 40 in Argentina, this would be a boring book indeed!

Travel along the eastern edge of the Andes is difficult—just ask any of the students who traveled with me in a circum-Andes trip in 2008. The >1000 kilometers (>600 miles) between El Chaltén (50 degrees latitude) and Bariloche (41 degrees latitude) is noteworthy because it separates two popular tourist destinations. Hence, the infamous Ruta 40. No regular buses ply this route because much of it is still gravel. But one company has found a niche by providing service every other day—it takes two very long days of continuous travel to make the trip and is the stuff of legends for those who have done it. Services are basic. The photo below is a bathroom stop. It reminded me of field trips—men on one side of the road, women on the other—but clearly most people aren’t used to doing their business in public this way!

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The drivers are very informal. Of great importance is the continuous drinking of mate, so as soon as the bus stops, one of the drivers is immediately heating more hot water for their thermos! On the second day, a “coordinator” provided comic relief and went around to all of the seats asking passengers about their plans and providing them with suggestions.

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Here is the view from the bus, through the front window. It is very flat in all directions on most parts of the Patagonian steppe.

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So we were reminded a lot of Nevada. Not only because of the lonely road, but also because of the dry climate in the rain shadow of a large mountain range and because of volcanic rock formed from extension east of the main cordillera. Fortunately, we found a small local tourist company that took us on a 2-day tour of the area, mid way, to explore the amazing geology of the region and to break up the grind of La Ruta 40.

We saw a lot of really cool rocks!! I’ll save those details for the guide book and focus on the rocks that would appeal to almost anyone—the rocks with 9,000-year-old art on them. The only thing that is known about this ancient aboriginal people is their art, which has managed to be well preserved through the years in this arid climate. The location, near the town of Perito Moreno about halfway between El Chaltén and Bariloche, is called Cueva de las Manos (cave of the hands).

They aren’t caves in a strict sense. Rather, they are overhangs of rocks formed because a less-resistant layer of volcanic rock eroded away beneath a very thick, more resistant layer above. The art is on the vertical walls beneath the overhand shown in this photo.

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When the aboriginal people lived in this area, they followed the route of the guanacos, the camelid species related to the llama that is so common in this region, and that was essential to the life of the native people who used every part of the animal. In the art work below, there are many guanacos and also the native hunters who are surrounding the animals.

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But what has really captured the world’s attention (it was declared a Patrimonial Cultural de la Humanidad UNESCO site in the 1990s) is the hand prints that are unique to this location. They are done as negatives—that is, they “sprayed” paint around their hands to make the print. It is thought that their method of spray was to blow rock powder of different colors using a bone or just their mouths. The black color is manganese oxide and ground charcoal that provided enough material for radiocarbon dating (to know that the site is 9,000 years old).

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Archeologists have puzzled over the meaning of the hands, but the interpretations will always be speculative. One thing that is not mysterious is why the people chose to hang out and do their art work here. It is a beautiful canyon carved into volcanic rock that is an oasis in the surrounding desert (the rock is ignimbrite or ash-flow tuff for those who care about these things). Jay says it looks a lot like the area of SE Oregon / SW Idaho / NW Nevada where he did field work for the U.S. Geological Survey in the 1980s.

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Speaking of critters (human or otherwise) we finally saw several armadillos roaming above their burrows. These are small ones that are here called “piches”—they are much different than those huge Texas varieties).

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Here also is a photo of our favorite fossil so far—a complete crab from the Mesozoic. This is certainly a successful design as the form they take has changed little over so many millions of years. We did not see it “in situ” but it was collected by the owner of a hospedaje (small family place for lodging) where we stayed. We are sworn to secrecy about the location!

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Finally, another photo of the rock art. This one is what the archeologists call the “third period”, when the art became more abstract (circles and zig zags). I think the hands were like their signature—a mark that said “we were here”. What do you think?

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Postscript—Internet connections along La Ruta 40 were poor. Hence, the paucity of postings.

Whispers of rock

If climbers are straining to conquer the scream of raw stone, geologists are straining to hear the whispers of rock that often yields its secrets reluctantly. Learning to “read the rocks”—to decipher Earth’s history—is like reading a story where most of the pages are missing, and the pages that remain are shuffled into a random order. So learning to interpret Earth’s history involves trying to put the pages into their proper order and using a lot of imagination to fill in the pages that are missing entirely.

Two PhD students who are working with Steve Graham, the same professor who was my graduate research advisor at Stanford University in the 1980s, are doing field research in the area around El Calafate and El Chaltén to decipher the history of the sedimentary rocks in this area. As luck would have it, our time in El Chaltén has overlapped with one of the student’s period of field investigation here. So we have spent parts of several days in the field with Matthew and his field assistant Corey. Here we are (photo from Jay), with Matt explaining the large size of the boulders in one of the sedimentary deposits.

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Steve’s students have been working in the area south of here, around Torres del Paine national park in Chile, for a decade or more. They have read the clues to establish a complete chronology (sequence of events through time) that continues to be refined. Matt’s job is to extend that work to the north—to the El Chaltén area—where the details remain obscure. Here I am with Matt and Corey and the geologic map of the region, which at this point is not very detailed (photo from Jay).

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Here is the basic story—as Matt can tell you, the devil is in the details! In the Jurassic Period (Mesozoic Era) the continents that were united as Gondwana begin to separate and the Atlantic Ocean began to open. In Patagonia, rifting created a large ocean basin that continued to subside and fill with sediments that were mostly mud. Here is the field team looking for clues in the mudstone, with Cerro FitzRoy as backdrop (photo from Jay).

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Fossils are, of course, one important clue. This locality is famous for ammonites, a marine organism that evolved rapidly throughout the Mesozoic and that went extinct when the dinosaurs did, at the end of the Mesozoic. So these fossils are important for putting the layers of sedimentary rock into their proper order. Here is a photo (from Jay) of an ammonite from the site shown in the photo above. There can be no collecting, however. Much of the geologic mapping here has been done in the context of paleontology, and in Argentina fossils are a serious matter. You would not want to be caught leaving the country with samples in your luggage.

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During the Cretaceous Period (latter part of the Mesozoic) this entire region was compressed and, although the marine basin continued to exist, more sand began to be supplied from areas uplifted above the water. Here is an example of a sand bed that is graded—that is, there are larger sand grains at the base and smaller grains toward the top. We interpret these beds as deposits of turbidity currents that are basically underwater debris flows. As the flow moves seaward from the land, the slope becomes more gentle and the sand falls out of the water to make a graded bed.

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Other evidence of the compression is the abundant folds that are visible throughout the area. Imagine that you take a flat piece of paper (the original layer of sediment) and squeeze it until it’s crumpled. That would make a fold. Here are some beautifully exposed folds on the hill slope along the road between El Calafate and El Chaltén.

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Many complex structures were formed during this period of contraction. Our hike to the top of Loma del Pliegue (slope of the fold) left us puzzled when we didn’t see the fold. But on the following day, on a hike in the valley below, the fold was clearly revealed on the side of the slope. These layers were folded so much that the top layer is completely upside down (take that piece of paper and squeeze it so the one side of the paper faces downward). It’s hard to get the scale of this fold, but a person would be only a tiny speck on the top of the peak.

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Finally, a note about the culture of geology. Geologists like to drink beer, so it’s certainly a bonus when the local town has a microbrewery! This is a popular spot for everyone in El Chaltén, not just for geologists.

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Geologists, also like many others, are attracted to mountainous landscapes in exotic locations. Here is the field team with Cerro Torre as backdrop. Field sites don’t get much better than this! (Person on the left is a German traveler who accompanied us for awhile to learn more about what geologists do.) Matt and Corey are now on a several-day excursion to a more remote location east of here. We wish them success in their continuing investigations.

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Scream of stone

“Scream of Stone”—an aptly named, feature-length film by Werner Herzog documents the personalities, egos, and drama involved with a climbing expedition to Cerro Torre. It’s shot on location and includes stunning footage of the mountains here. Although lower in elevation than Cerro FitzRoy (3100 meters compared to 3400 meters) Cerro Torre makes up for its diminutive stature with steeper slopes, harsher weather, and a cap of rime ice that can frustrate climbers trying to reach the very top. Rime ice forms when super-cold water (<32 degrees F) freezes upon contact with solid objects like trees or, in this case, rock. In the photo below (view from the east), rime ice is visible at the top of Cerro Torre and adjacent smaller peaks where water droplets froze onto the rock as they blew from the west, off the Patagonian ice field.

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Lots of folks have written about the drama of climbing these granite spires. I recently read “Enduring Patagonia” by Gregory Crouch, who also writes articles about climbing for outdoor magazines. It’s a good book for taking you inside climbing culture—the shear boredom of waiting for weeks in base camp for the weather to improve; the stress of trying to make progress up or down a rock cliff while the weather is deteriorating. The first time he could only make it to the base of the infamous “mushroom”, the uppermost piece of rime ice that often has a nasty overhang. On another attempt he was able to make it to the top of the “mushroom” and look out upon the ice field. That top part of the peak looks incredibly nasty to me!

To demonstrate the fickle nature of the weather here—on Wednesday the forecast for the next two days was clouds and drizzle. But it rained during the night and we awoke to crystalline skies and perfect mountain views (Darwin is still smiling upon us!). On Thursday we hiked to a peak that was intriguing for a variety of reasons. It’s called Loma del Pliegue (slope of the fold) for the geologic structure that makes it up (see next posting!); the mudstone is filled with ammonite fossils; and best of all, there is a spectacular view of the entire range. In the photo below, Cerro Torre is on the left, Cerro FitzRoy is on the right, and Glacier Grande flows into Laguna Torre that has formed behind the most recent terminal moraine that is the curved hill of rocks in front of the lake.

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How did the peaks get so jagged? You guessed it—the action of glacial ice! Globs of magma cooled deep within the earth to form the granite about 20 million years ago. Since then, they were uplifted to Earth’s surface, where they could be sculpted by glaciers. Granite is very durable and is one of the best rocks for ice to carve. The granite intruded into much older Mesozoic (>100 million years old) sedimentary rock that is mostly mudstone that crumbles when subjected to the action of ice. The next photo shows Cerro FitzRoy and the black mudstone the granite pushed its way into 20 million years ago. The mudstone has been much more eroded, and the more durable granite spires remain at higher elevations.

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After the panoramic view, we yesterday hiked to Laguna Torre, which we had seen from the “fold hill” above. The photo below is taken from the terminal moraine, looking east toward Cerro Torre, Glacier Grande, and Laguna Torre. Note the size of boulders (people for scale) that were dumped by the glacier before it receded. A climbers’ base camp is located just behind the moraine, at about 600 meters elevation.

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Here’s a profile (cross sectional) view of another recessional moraine, located farther east in the valley, and Rio FitzRoy, which has its work cut out for it—carrying all of those large boulders away from the glacier to the flat lands below.

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Finally, an example of the eclectic town of El Chaltén. At the start of the Laguna Torre trail is a cute little trailer where a family sells drinks and snacks to trekkers! Note the “toque timbre” (ring the bell) sign! And below that, yet another view of this stellar mountain range. Although it was a sunny day, the winds were still fierce on the ridge top.

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A mecca for climbers—and anyone who loves mountains

We are back in Parque Nacional Los Glaciares (Glacier National Park), this time in the sturdy little town of El Chaltén, located right at the edge of the park. It consists of lodging, restaurants, excursion companies—everything geared to the people who come here from all over the world to climb and hike during the summer season. Here is a photo of the town, which is nestled into a valley on the edge of the national park.

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The amazing thing about this place is that you access most hiking trails by walking directly from town. Climbing the granite spires of Cerros FitzRoy and Torre, and hiking to see these peaks and the glaciers that have carved them, are THE attractions. We were stunned to see Cerro FitzRoy appear just after we arrived in town yesterday afternoon. The photo below was taken from in front of the place where we’re staying in town.

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Cerro FitzRoy was named by Perito Moreno (intrepid explorer and naturalist) for the captain of the Beagle. But the aboriginal people had already named it El Chaltén or “god of smoke” because of its almost permanent veil of clouds. Well, at least the town still retains the original name.

Today we hiked to Laguna de Los Tres, a cirque lake at the bottom of the three FitzRoy towers, and an access route for rock climbers. The difficulty here is not the elevation—the mountain is only about 3400 meters (about 11,000 feet) above sea level. The difficulty is the extreme and rapidly changing weather conditions. In El Chaltén town, even in the summer the highs are in the upper 50s and the wind is fierce. In the mountains it is much more extreme and snow falls anytime of year.

The photo below is of the three towers from Laguna de Los Tres, at an elevation of just over 1200 meters. It was not possible to see the top of FitzRoy (rightmost of the three towers), but even the bottom of the tower makes a breath-taking view. Try to imagine, if you will, climbing up this tower to the very top (it’s 36 hours of continuous climbing for those with enough skill to attempt it).

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Like in Yosemite Valley, the towers are made of granite, the favorite rock of most climbers. Unlike in Yosemite, this granite is not part of the long continuous range. Rather, it is a small igneous intrusion, and most rock in the area is older sedimentary and volcanic rocks (more on that later).

The Laguna is a beautiful cirque lake that formed when the melting glacial water filled the bowl that was formed by ice erosion. Here is a photo of the lake and the receding glacier.

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Looking the other direction shows the terrane traversed to get to the Laguna. The town of El Chaltén is not visible in the narrow valley separating the forested area in green from the hills in the distance.

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A note on travel options: It is possible to travel by bus between Patagonia and Tierra del Fuego, but it is a long distance. Rather, we choose to take a short (one hour) flight between El Calafate and Ushuaia. From El Calafate, we got a bus (3.5 hours) to El Chaltén, which most people visit for just a few days (it doesn’t even have a bank or an ATM!) We will stay for 6 days though—we loaded up on cash before making the journey here!

On the way to El Chaltén, Jay took a photo of the Argentina flag, with its sun and blue stripes against the sky seeming an appropriate symbol of this place.

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Tectonic plates at the end of the world

As we have headed south, we have gotten closer to active plate boundaries – closer to the convergent plate boundary (subduction zone) along the western coast of Chile and closer to Argentina’s only plate boundary – the transform boundary between the South American plate and the Scotia plate. Below is a map of the plates in this region.

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You may notice that the Scotia plate is sliding to the east, relative to the South American plate. That makes the transform plate boundary (Magellan fault on the map) a left-lateral strike-slip fault – the opposite sense of our own San Andreas fault, which has a right-lateral sense of motion between the Pacific and North American plates.

Yesterday we rented a car to travel across the plate boundary, which in most places is covered by water of Lake Fagnano. Like all of the lakes and fjords in this part of the world, this lake was recently occupied by a glacier and there are abundant fluvio-glacial deposits along the edges of the lake, where streams carried sediments away from the melting glaciers. The photo below is looking west along the length of Lago Fagnano and the plate boundary. The red-roofed buildings are a hosteria that would be an amazing place to stay, with views of the lake and the cordillera (the Andes) to the west and south.

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On the map above, you will notice that the Patagonian Andes are oriented north–south, like the rest of the Andes farther north. However, the cordillera bends eastward at the south end of South America, and the Fuegian Andes are here oriented east–west. Like the rest of the Andes, the core is located toward the Pacific coast, and the rocks are progressively younger and less deformed eastward (here northward) toward the Atlantic coast.

We continued northeast from the plate boundary to the Atlantic Coast at Cabo San Pablo – a headland from which there are stellar coastal vistas. As we saw along the Atlantic coast of Patagonia, there is uplift of the land that has created terraces along the coast; there are vast quantities of gravel on the beaches that were carried by rivers from the Andes; and there is a large tidal range that results from amplification of the tides by the broad continental shelf in this region. We were fortunate to arrive at low tide, when a very broad wave-cut platform was exposed. In the photo below you can see the platform and a ship on the platform that wrecked, probably because it ran aground, not realizing the water was so shallow so far from the land (it’s very rusty and has clearly been there for many years). In the foreground, you may also be able to see a small fault in the marine sedimentary rock that was eroded to make the wave-cut platform.

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On the next photo you can see an immense amount of gravel on a beach berm on the north side of the headland. Note the variety of rock types, including white rocks that are vein quartz – more on that later.

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It was totally awesome to stand on the coast, where there are the younger Cenozoic sedimentary deposits that are barely deformed, and to look southwest to see the cordillera (Fuegian Andes) that are older, highly deformed, and the source of gravel found on the beaches – at least the rock types that are durable enough to withstand the trip to the sea via rivers. On the photo of the coast (above the gravel berm photo), you may be able to see the cordillera just barely poking up above the horizon in the distance.

We did not see any interesting marine critters on this part of the coast but we did see lots of guanacos as we traveled back from the coast. Here is a group of guanacos with some babies, one of which is having its lunch (photo courtesy of Jay).

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Traveling back south to Ushuaia, we stopped at the Garibaldi pass, which is the highest point on the road before descending to the Beagle Channel. This is a good place to get a sense of the contrast from north to south. The first photo is looking north across the Lago Fagnano / plate boundary that I’m showing with my finger (the lake in the foreground is oriented perpendicular to the plate boundary). Photo is courtesy of Jay – I had to include it to show t-shirt advertising the student club in our Geosciences Department!

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The next photo is looking south at the pass, at a road cut into the rocks at the core of the cordillera. Even for geologists, these are ugly-looking rocks! They are highly metamorphosed and deformed and we decided we would really not like to have to decipher their history!

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On Friday, we saw more of the old deformed rocks in the national park – Parque Nacional Tierra del Fuego. These rocks were more attractive though, certainly aided by their scenic location along the Beagle Channel. There are green schists that erode to make unusual green-sand beaches; also note the abundant white vein quartz that is the source of the white pebbles we found on the Atlantic Coast beach.

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Here’s a close up for those who want to see the deformation in more detail! (Those are size 11 shoes for scale. Some of the quartz veins are green from the marine algae.)

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As in most national parks, this one is now a refuge for plants that can no longer be logged. So there are large trees of nothofagus, the southern beech tree that evolved >100 million years ago, when the continents were together as the super-continent Gondwana. As the continents moved apart, the trees remained and the same species is also found today in Australia and New Zealand – another piece of evidence that these locations were once adjacent to each other. Below is a photo of the lenga tree, the largest of three types of nothofagus in this region.

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Finally, a note about the weather. Our guide at the penguin colony the other day said that Ushuaia has only about 10 days/year that are sunny all day. We had one of those Friday, when we enjoyed a cloudless, warm day hiking in the national park. Yesterday was about as good and we’ve really had amazingly weather for our five days here – even the wind has not been so fierce. We feel as if Charles Darwin is smiling down upon us, as we sate our curiosity about the natural environment as he did here nearly two hundred years ago. So that friends and family can see that we’re doing well, here we are (self-timer shot) with the Beagle Channel and Darwin Range in the background. We really do wish you were here.

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Ushuaia – el fin del mundo (the end of the world)

Ushuaia is the southernmost city in the world, at 50 degrees south latitude. True, there is the small town of Puerto Williams that is slightly more south, on the south shore of the Beagle Channel, and there is a small scientific settlement (McMurdo Station) in Antarctica, but Ushuaia is a bustling city of about 70,000 people that takes full advantage of its “fin del mundo” status. It is beautifully situated on the north shore of the Beagle Channel (named for Darwin’s vessel), where it is backed by rugged, ice-sculpted mountains. It seems somehow incongruous to see a busy port with cargo ships, cruise ships, and military vessels, adjacent to such stunning scenery (photo below).

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Ushuaia is located in the Argentina province of Tierra del Fuego (land of fire). As in Patagonia, the glaciers that covered the land 20,000 years ago are now very small. While glaciers along the eastern side of the Patagonian Andes carved valleys that are now lakes, on the western side of the Patagonian Andes (in Chile) and to the south (in the Fuegian Andes) glaciers advanced to the sea and, when they melted, the valleys they created filled with ocean water. At the southern end of South America, these deep channels, called fjords, create a vast network of marine pathways. How did explorers first find their way through this maze?!

Located only 7 kilometers from town is the Martial glacier that is visible from just about everywhere in town. This view is from the western side of town, at the CADIC (Centro de Investigaciones Cientificas – more about that below). In front of the glacier is the U-shaped valley that the glacier created when it flowed all of the way to sea level, about 1000 meters below.

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Yesterday we walked from town to the glacier, aided only by a short chair lift that was constructed for wintertime skiing. How amazing to look all of the way down the Beagle Channel (view to the southeast – Jay for scale!) and imagine the valley and channel completely filled with ice and only a few small peaks sticking out.

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Downslope from the glacier, the bedrock is smoothed and polished, a distinctive feature that says “glaciers were here”. In this photo, Jay is standing on rock that is shiny from the glacial polishing. Other climbers in the background are celebrating their success in reaching the ice!

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The bedrock in this area does not polish as well as our granite bedrock in the Sierra Nevadas. This rock is Mesozoic mudstone that breaks apart more easily and doesn’t “take a polish” so well. Still, we were entertained along the way by the deformational features in this metamorphosed mudstone. The sample below shows several sandstone layers that were once horizontal but that were since subjected to high temperatures and pressures deep in the earth.

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Speaking of the Mesozoic, we today visited CADIC, where many geologists, oceanographers, and biologists conduct scientific research (much like our U.S.Geologic Survey). Because it is summer here, most of the geologists are in the field or on vacation, but we were fortunate to meet with a paleontologist who was very helpful and who showed as an amazingly large and complete ammonite they had found in Antarctica. Her group also found the first dinosaur in Antarctica – this made international news in the 1980s. These two life forms both went extinct at the end of the Mesozoic Era.

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Yes, you penguin lovers, there are penguins here too! Today we visited a penguin colony on an island that seemed very well run – only 80 people/day are allowed on the island and human paths are quite restricted. Still, we were able to get close to these entertaining birds. The majority of the penguins are the Magellanic species, which the type we saw along the Atlantic coast. We were also fortunate to see the Papúa penguins, with their colorful orange feet and beaks (photo below and at the end). These penguins normally live in Antarctica but for some reason decided to relocate to the Beagle Channel.

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Even more amazing was one King penguin who is also from Antarctica. He apparently has gotten lost but has at least found another group of penguins to hang out with for awhile. Neither he or the adjacent Magellanic penguins seemed too bothered by the situation. His orange and black coloration is remarkably elegant.

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