Thursday, August 6, 2009

On the Road Again - Post 12

Today was a driving day, but around here even getting from one place to another offers a scenic masterpiece. Here are pictures from the road between Evanston, Wyoming, and Torrey, Utah:

The mountain in the picture below is Mt. Timpanogos, so named after a pair of doomed lovers. According to a nearby sign, Ucanogos was the lovely daughter of the chief of a tribe of Indians living on the shores of Utah Lake. She was in love with a young brave called Timpanak. Her father nevertheless held a contest to determine whom she would marry. Jealous of Timpanak, the other braves killed him and threw his body down the mountain. Ucanogos climbed the mountain and died atop it, grieving. The mountain then took on the outline of her body, and it has been called Timpanagos (a combination of the lovers' names) ever since.

Wednesday, August 5, 2009

On the Road Again - Post 11: Gold Rushes & Ghost Towns

Gold strikes and the towns that spring up around them evidently follow a rather sorry pattern most of the time. Gold is discovered, usually in a "meet-cute" story worthy of a romantic comedy. Thousands or tens of thousands of people flock to the area and a boom town is born. Lawlessness, vigilantism and high hopes abound; non-gold-claim-related infrastructure is entirely absent. Then the gold runs out, and so does the town's raison d'être. The once prosperous boom town becomes a ghost town, nothing more than a name on a map and, sometimes, a few rickety buildings.

Bannack was the town that boomed in response to the first of Montana's three major gold strikes. It was the first territorial capital when the Montana Territory was carved out of the Idaho Territory in 1864, but it held that honor very briefly and was a ghost town by mid-1865.

Why? Bannack's easily accessible gold was exhausted and word of a new strike had spread. A group of prospectors on their way to the Yellowstone River encountered an unfriendly bunch of Crow tribesmen and had to beat a hasty retreat. Legend has it that on the retreat, one Bill Fairweather made a joke about finding something that would fund the purchase of some tobacco, stuck his pick in the ground near Alder Creek, and came up with something that funded a very large amount of tobacco and a whole lot more.

Fairweather and his buddies couldn't keep their find a secret, and Virginia City sprang to life a mile or so south of the gold field. Within a few weeks, it boasted 10,000 residents (many of them refugees from Bannack and most of them arguing about individual gold claims) and it was in short order named the new territorial capital. Like Bannack and most of the rest of Montana, Virginia City was ruled by a Vigilance committee that operated on both sides of the law. Also like Bannack, within a year or so it too was a ghost town, its population having lit out for Helena in response to the Last Chance Gulch strike.

Bannack is now a state park, preserved but unrestored. Virginia City was reborn as a tourist destination in the 1950s, thanks to the efforts of a couple who bought the town in the 40s and funded its restoration. While it is no longer home to 10,000 as it was in 1865, Virginia City is far from deserted. Some 130 people and, according to local lore, more mean-tempered and obstreperous ghosts than in any other city in Montana call it home.

Click on the picture below to get some fun info about Bob Gohn's grandfather. Bob is the owner of Bob's Place (above) where we bought surprisingly sophisticated sandwiches for lunch. With their pesto, fresh tomatoes, delectable cold cuts and superb focaccia, the sandwiches were anything but authentic Old West, but we weren't complaining.

Tuesday, August 4, 2009

On the Road Again - Post 10: Glaciers

Borders, like time, have always seemed a little silly to me. They're merely constructs, real only because we agree to consider them so. At the Waterton-Glacier International Peace Park, established in 1932, Canada and the United States decided to agree otherwise for one segment of the line on the map dividing them. Marked only by a couple of white markers, one on the ground, one high atop a ridge, and a swath cut in the forest at the 49th Parallel, that segment is the longest undefended border in the world.

The peace and trust signified by the decision to ignore the border seem utterly at home in serene Upper Waterton Lake (pictured above) and the rest of this magnificent park. There's a super-abundance of beauty here: craggy peaks; gentle slopes; sheer drops; deep chasms carpeted in green and taupe; thick forests; glittering waterfalls; vast pristine lakes hundreds of feet deep, most of them astonishingly clear, others tinted turquoise by suspended glacial silt; even the engineering marvel that is the Going-to-the-Sun Road.

I've written about these beauties before and barely scratched the surface. It's tempting to go over that territory again or to mention cool facts I left out the first time, such as Triple Divide Peak. The Continental Divide winds its way through the Northern Rockies; at Triple Divide Peak, not two, but three watersheds intersect. Depending on exactly where it falls on the Peak, a raindrop will ultimately end up in the Hudson Bay, the Pacific Ocean or the Gulf of Mexico. An area only as big as the span of a hand determines which direction the drop will travel.

Instead, though, I'm going to write about glaciers, my absolute favorite geological phenomenon and the reason Waterton-Glacier looks the way it does. Its topography is a textbook illustration of the effects of glaciation - if the textbook were the educational equivalent of an illuminated manuscript.

Glaciers cover about five million square miles of Earth's surface, four million over Antarctica, 750,000 over Greenland and the other quarter-million scattered around the rest of the world. Glacial ice is the largest reservoir of fresh water on the planet, and is second only to the oceans as the largest reservoir of total water. As such, glaciers are crucial to both world water resources and variations in sea level.

And they are fast disappearing. In Glacier NP, for example, there were 150 at the end of the cooling trend known as the Little Ice Age (1550-1850). By the middle of the 20th century, there were 50; in 2005, there were 27. If global warming continues at current levels, all the glaciers in the park will be gone by 2030.

That will be very sad, not only for aesthetic, fresh water or sea level reasons, but also because glaciers are an extraordinary phenomenon and the sculptors of some of the most striking landscapes on Earth. Glacial ice comes in second to streams as an agent of erosion, but what a glorious second.

Glaciers are the beautiful ice-blue result of climates cold enough to permit snow and ice to survive year-round. When over time the amount of snow that falls is greater than the amount that melts, a remarkable transformation takes place. Delicate snowflakes are converted by a process called sublimation into vapor that instantly recrystallizes into a granular ice called firn or névé. The sand-sized crystals then bump into each other and melt at their points of contact. The resulting water flows into the spaces between the grains and instantly refreezes, creating a mass of glacial ice.

Once the mass reaches a thickness of 150 feet, the weight of the top ice causes the bottom ice to become plastic and flow. Remember, in geology "plastic" means neither a liquid nor a solid. The rocks in the asthenosphere portion of the mantle are likewise plastic and for the same reason: the weight of the overlying rocks in the lithosphere. Plastic flow occurs because the ice (or, in the case of the asthenosphere, the rock) is composed of layers of molecules stacked on top of one another with relatively weak bonds between the layers. When the stress caused by the weight of a higher layer exceeds the strength of the bonds between the layers, the top layer moves faster than the layer below. Voil
! Plasticity.

I understand plastic flow and I can explain it, but it seems magical to me anyway and it's one of the big reasons I love glaciers. Another is the way they operate. As glaciers advance (which means grow in size), they erode the rock under them spectacularly. They're very workmanlike about this, despite the dramatic results. Glaciers physically remove chunks from the underlying bedrock and pull them up into the ice. (This process, called quarrying or plucking, is accomplished by the very same eons-long freeze-thaw process that carved Bryce Canyon's eye-popping rock formations.) The rocks so taken up in the ice abrade the bedrock over which the glacier moves, effectively turning the flowing ice into a colossal piece of sandpaper that scours, polishes and stripes the surface below.

Glaciers come in two varieties: the stodgy-seeming continental (like Antarctica and Greenland) and the flamboyant alpine (like the rest). What they do is identical: form, advance, retreat, and erode the landscape. How they do it and what it looks like when they're done are very different.

Continental glaciers form only in polar regions and they sit on huge horizontal surfaces. Constantly falling snow causes the ice to collapse under its own weight, which moves the whole mass. The movement is very slow, only
15 feet or so per year. When they eventually retreat, continental glaciers leave landscapes that look like Canada east of the Rockies or the Finger Lakes region of upstate New York. This topography may seem boring, but it is, in fact, the result of ultra-dramatic glacial activity. Advancing continental glaciers actually increase the relief of the bedrock over which they move. But when they retreat (think "melt"), they deposit gigantic loads of glacial till (the stuff they've quarried along the way over eons). The till piles up and piles up, and eventually it reaches and buries the high-relief peaks, turning the landscape into flat or very gently rolling plains dotted with depressions where water collects into lakes.

Alpine glaciers are the showboats, much flashier in terms of how they move and the landscape they leave behind. They form in the headwaters of V-shaped mountain stream valleys. First, the growing mass of ice digs a bowl into the mountainside called a cirque. Eventually, the ice overflows its cirque and goes careening down the mountain (well, geologically speaking - the rate of movement is typically a foot or so a day). The glacier spills into the stream valley below and transforms the existing V-shape into the tranquil, soothing U-shape characteristic of glacially created valleys.

Alpine glaciers indulge in a bunch of other acrobatics as well. They can form in adjacent valleys on two sides of a mountain and eventually sculpt knife-sharp ridges (aretes). They can tunnel through ridges and create high mountain passes (cols). They can get together and gang up on all sides of a mountain peak to create a horn (think of the Matterhorn or the Grand Tetons).

The forces of gravity that caused alpine glaciers to spill down mountainsides in the first place are still at work when these glaciers retreat. They deposit their quarried loads in moraines below and sometimes astride the cirques, filling up valleys (remember Jackson Hole?), but leaving the highest ground craggy, the cirque basins filled with glacier remnants or cold clearwater lakes (called tarns), and the slopes down which they flowed polished, striped and spectacular. The sculpting effected by alpine glaciers is superimposed on topography already carved by streams, and the combination is what we have to thank for scenery as incredible as the Northern Rockies and the Alps.

Although they, too, are in retreat, the Mendenhall Glacier in the Juneau icefield and especially the Hubbard Glacier in Alaska's Yakutat Bay retain miens of power. It is possible to look at them and see as well as comprehend the gargantuan work they've done and still do.

By contrast, the glaciers in Waterton-Glacier NP are small, outwardly inert, sad even. They seem to be clinging by their metaphorical fingernails to their cirque basins and mountainsides as if for dear life. If you know nothing about how glaciers work, you might find them pathetic. Armed with knowledge, however, you have to be impressed. With their dazzling handiwork spread out around and below them, Glacier's glaciers are like proud great-grandparents at the head of the table - aware that their work is done and content in the realization that they did a superlative job.

We saw a veritable wildlife jamboree on this visit: a black bear; a perfectly posed ring of bighorn sheep; a more independent, but equally picturesque, lone bighorn; a deer wandering through the Logan Pass parking lot looking for all the world like a prospective car buyer checking out the inventory; three mountain goats, including the baby pictured below; a stag that sauntered up to a hedge, sat, stretched his elegant neck, posed thusly for 15 minutes, then rose and sauntered off, his shift apparently over; and another black bear.