Posts Tagged ‘glaciers’

Patagonia: Five Things

Monday, May 10th, 2010

The Perito Moreno Glacier. Photo: Allison Dale

The unseasonably hot and humid weather we’ve had in Washington, DC, lately had our staff discussing cooler climates. This got us thinking about snow, then ice, and then glaciers, which led us to Patagonia. Here’s five things you should know about Patagonia, where during a heat wave, temperatures might reach all of 78 degrees Fahrenheit.1) The explorer Magellan named the region, which includes the southernmost portions of Chile and Arentina, after the native people there. He used the word Patagón, or giant, to describe the group, who were an average height of about 6 feet tall, much taller than the Europeans of the time.

2) Rawson, the capital of the Chubut region of Patagonia, was settled by Welsh immigrants in 1865, as part of an effort by the Argentinian government to attract settlers to areas outside of Buenos Aires. The going was even tougher than they anticipated; the settlers had been told the arid plateau of Chubut was much like lush, green lowland Wales.

3) The Patagonian region of Santa Cruz, in Argentina, is home to a 52-square mile petrified forest. The forest grew 150 million years ago, during the Jurasssic period, and was later buried under volcanic eruptions at the beginning of the Cretaceous Period, when the Andes began formation.

Cave Paintings at the Cueva de las Manos in Santa Cruz, Argentina. Photo: Mariano Cecowski.

Cave Paintings at the Cueva de las Manos in Santa Cruz, Argentina. Photo: Mariano Cecowski.

4) Humans have inhabited Patagonia since 10,000 BCE, if not longer, and traces of past settlements can be found across the region. One of the best known is the Cueva de las Manos (cave of hands), located in Santa Cruz, Argentina. The cave painters used ink made from hematite, and some archaeologists speculate that the young men stenciled their hands on the cave as part of a tribal rite-of-passage ritual. The cave was designated as a UNESCO World Heritage Site in 1999.

5) Some of the most famous residents of Patagonia include the Magellanic penguins of Magdalena Island. Situated in the center of the Strait of Magellan, Magdelena Island hosts 60,000 breeding pairs of penguins. Penguins mate for life, going back to the same nest to meet and breed each year.

Need more reasons to travel to Patagonia? Check out Smithsonian’s new Patagonian Frontiers tour, where you’ll explore the glaciers, islands, and windswept landscapes of Tierra del Fuego, the Beagle Channel, and more.

Ushuaia, Argentina, the world’s southernmost urban center, is 6,500 miles away from Washington, DC. What’s the furthest you’ve ever been from home? Please share.

Q&A With Jim Zimbelman: Iceland

Tuesday, March 9th, 2010

Dr. Jim Zimbelman is a planetary geologist at the Smithsonian’s National Air and Space Museum. He’s also study leader for our Exploring Iceland tour. Here, we quiz him about what Iceland’s unique geology can teach us about other worlds, as well as our own.

Iceland’s Namaskard geothermal area

Smithsonian Journeys: Of all the terrestrial and extra-terrestrial imaging and mapping that you’ve done, how does Iceland’s landscape compare in beauty, drama, violence?

Jim Zimbelman: Iceland is unique in my experience, either for sites of other fieldwork here on Earth or areas that I have examined using spacecraft data. No other place on Earth provides such good access to a mid-ocean ridge; tens of thousands of miles of the global ridge system are beneath the surface of the ocean, but an active oceanic ridge is only above water in Iceland. The geology of Iceland is therefore very helpful for those of us trying to understand volcanic terrains on other planets. With regard to the dramatic, no volcanic location I have visited has the combination of lava flows, glaciers, rivers with large waterfalls, and polar desert vegetation that can be found everywhere in Iceland. Fortunately, Iceland is not violent; even major eruptions can be safely viewed from fairly close distances, much like eruptions in Hawaii.

SJ: The huge volume of water that surges over the Dettifoss and Iceland’s other waterfalls and powers down the glacial rivers – where does it come from? Is it “young” water from recent precipitation? Is it ancient water from glacial melt? What “pumps” it to the surface with such force? Is it the volcanoes under the glaciers and lakes?

JZ:The water in the rivers of Iceland is both young and old.  Every winter the country is blanketed in new snow that in the spring then feeds large runoffs. However, the glaciers are also melting, releasing water that fell as snow tens of thousands of years ago. Both water sources mix together to make the dramatic rivers of Iceland.  The ‘force’ comes from the sheer volume of snow and ice available to feed the rivers; the volcanic bedrock does not need to add additional force (although, when an eruption occurs directly beneath a glacier, the resulting enormous flood when the melt water finally bursts out from beneath the glacier has an Icelandic name – jokullaupe).

SJ:  When and how did scientists realize that Iceland straddles two tectonic plates?

JZ: For centuries scientists realized Iceland had a very strong volcanic component to its history. The realization of how Earth’s crust moves in different plates is a fairly recent development. Individual scientists speculated about it early in the twentieth century, but the globe-encircling concept of plate tectonics was only accepted by the worldwide geologic community beginning in the 1960s. Iceland played an important role in this realization, since it allowed scientists to visit (and measure) the separation of two active plates.

SJ: Given the turbulent geologic history of Iceland, how much has the island changed (size, shape, elevation, climate, etc.) since the earliest Norse/Celtic settlements (est. 7th century?)?

JZ: Iceland has not changed all that much since the time of the Vikings. The glaciers are smaller than they were a thousand years ago, but not all that much else has changed since the conditions as described in the Viking sagas.

SJ: Iceland’s fjords seem to be limited to the north and west coasts. Why?

JZ: The fjords are the result of erosion by past glaciers, and the north and west coasts had the steepest topography down which these ancient glaciers could move. Precipitation is usually heaviest on the NW side of the island since storm systems in the northern hemisphere tend to move from west to east.

SJ: How many times in geologic history has the crust of Iceland been recycled? And how old is Iceland?

JZ: I don’t know the age of the very oldest rocks in Iceland, but I have heard discussions of some rocks that are millions of years old.  Over 99% of the rocks in Iceland are volcanic in origin, and the rocks at the surface are typically tens to hundreds of thousands of years old.  Few of the rocks on the island have been ‘recycled’ in that Iceland does not experience subduction (where the moving plates get shoved into each other), which leads to classic steep-sided volcanoes like Mt. Fuji in Japan or the large volcanic cones along the west coast of the U.S.

SJ:Would you please elaborate on the Icelandic plume, which seems to persist through geologic time, yet wander (or is it the “subaerial” surfaces such as Iceland and Greenland which have wandered?).

JZ: Iceland does indeed sit atop a particularly strong ‘plume’ of magma rising up from the interior of the Earth.  The coincidence of this plume with the mid-Atlantic ridge system is, we think, just that, a geologic coincidence.  Greenland does ‘wander’ in the sense that it is entirely on the North American plate and it moves along with that plate.  Iceland is literally growing as it is pulled apart along the ridge system that runs across the middle of the country.  Each year roughly 2 centimeters of new ‘Iceland’ is formed as the two plates spread apart  along that ridge.

Cool Facts About Iceland

Wednesday, January 20th, 2010
Iceland's Blue Lagoon contains hot water created by the harnessing of geothermal energy.

Iceland’s Blue Lagoon contains hot water created by the harnessing of geothermal energy.

Iceland was first permanently settled by the Vikings in the 9th century, though Celtic monks and hermits had been living there previously. Click here for more from Smithsonian on the Viking voyage from Europe to North America.

Krisuvik, Grensdalur, and Hveravellir aren’t new lamps from your favorite retailer, they’re volcanoes. Learn more from Smithsonian’s Global Volcanism Program.

Iceland is well on its way to energy independence, with more than 70% of its energy coming from Iceland’s own renewable sources. Most of the country’s energy is geothermal—from the heat generated underground thanks to all those volcanoes. Iceland is also testing a small fleet of hydrogen-powered vehicles for the Ford Motor Company.

Thingvellir National Park, located in southwestern Iceland, is the original location of the Iceland’s open-air parliament, first established in 930 A.D. The park also features impressive geological formations, including a rift valley and the largest natural lake in Iceland. It was designated a UNESCO World Heritage Site in 2004.

Now is a great time to go to Iceland—click here for more information on our 2010 Wonders of Iceland tour.

Ever been to Iceland? Why would you recommend it to a friend?