Saturday, June 19, 2010

Denali National Park

Took the shuttle bus to the Eileson Visitor Center in Denali today. Private cars can only drive in the 1st 15 miles. Beyond that you have to take a shuttle bus or hike in. The weather was clear and we were fortunate to be able to see Denali (Mt. McKinley) clearly almost the whole time. Most visitors to the park do not as it is usually hidden in clouds. Even when it is clear in the rest of the park, Denali is so tall and massive it generates its own weather. The entire ride (8 hours of it!) was spectacular. Sometimes the colors of the mountains were muted tans, greens, and reds, other mountains were stark black and snow white against the bold blue sky. Words that come to mind are majestic, endless, intense, alive.
In addition to the mountains we saw 4 Grizzlies, a herd of Barren Ground Caribou, lots of Dall Sheep (the park was created to protect these), Golden Eagles, a Gyre Falcon (thanks to a birder on our bus), Snowshoe Hares and the most precocious Ground Squirrels.
























I think I am being stalked! Once again, Ohioans are following me. The girl behind me on the bus is from the Cincinnati area AND is a former student of Jill Russell's - one of the professors we are here to travel with. What are the chances of that???

Teacher Talk: Denali is 56 million years old, 20,320 feet high, and still growing at a rate of about 1mm per year. It is made of granite (formed after molten magma solidfied underground) which resists erosion much better than the shale, limestone, and sandstone that make up many of the other mountains in the Alaska range. The mountain range is forming as the Pacific Plate continues to collide with the North American Plate (a convergent oceanic-continental boundary moving at about 5 cm per year), causing folds in the North American plate. Denali is Athabascan for "great one".

The trees in Denali - in fact, throughout Alaska - are smaller than I expected. I was expecting enormous conifers such as those in the Pacific northwest. They are small due to the short growing season and to permafrost - permanently frozen soil that is not far from the surface. Because tree roots can't penetrate deeply, their growth is stunted. Our shuttle driver told us about a tree that was downed and was only about 12" in diameter. Scientists were unable to see any growth rings until they took it to a lab, dyed it, and viewed it with a hand lens. The tree was just under 500 years old!

Denali is full of "braided rivers" that are glacially fed. They look like really large rivers that have dried up and left behind a mostly empty riverbed. Braided rivers form when meltwater flows off a glacier and gradually deposits its sediments. When enough are deposited in one area it changes the path of the water and a new channel is formed. This is repeated over and over, hence the braided appearance.

1 comment:

Sam Kirschner said...

This is absolutely astounding scenery and wildlife. Hope all is going well on the trip, looks like you are getting to enjoy some pretty neat experiences.