Thursday, October 23, 2014

Partial Solar Eclipse from California (and What a Sunspot!)

Wow. Just wow. Yes there was a partial solar eclipse today that was visible across much of the country, and yes, it was pretty spectacular. But what caught my attention was the huge sunspot. It is the first time I've ever seen a sunspot with the naked eye, and it was incredible in the zoom lens. I'm told that it is more than 90,000 miles across, the width of 12 Earths. Sunspots are essentially gigantic solar storms. They look dark, but they are simply a bit less bright than the rest of the Sun's surface.
It was so big that even my camera was able to catch some detail. I had my camera on a tripod, and held a solar telescope filter over the end to catch these shots. The zoom was about 60x.
There was a lot of interest on campus, and so our astronomers and Astronomy Club had a number of scopes set out on the roof of the new Science Community Center. I wish I could have photographed one of the views through the most powerful scope. We could see the granules of the Sun's surface, and solar prominences, the arcing jets of plasma shooting out from the surface.
A great day!

Wednesday, October 22, 2014

Northern Convergence: Leaving a Beautiful Country

How will we deal with the hordes of people from the U.S. trying to invade our borders?
Our trip, the Northern Convergence tour, was not over, but the time had come to cross the border back into the United States from Canada. The trip thus far had been an eye-opener. We had been exploring the "crowded" part of Canada in British Columbia and Alberta, but the land itself exuded wildness and isolation.
We were on the High Plains east of the Rocky Mountains, and had spent the morning at the Head Smashed In Buffalo Jump World Heritage Site, and as gruesome as the name was, it was a fascinating place. From there we headed south to the border crossing at Carway. We figured since it had a name that there would be a town and facilities. We got there, and there building. It was a duty-free souvenir/liquor/tobacco shop, and thank goodness, it had a restroom. Still, there were some picnic tables so we stopped for lunch and had a look around. We also wondered if the authorities were going to let us back into the United States. You never the innocent days before 9/11, we were interrogated about whether we had any "Beanie Babies" in our luggage. I laughed at the question, and the border agent got very serious: "Sir, DO YOU have any Beanie Babies?"
We were not exactly in the High Plains, as the land was broken up into swales and shallow valleys underlain by very soft Cretaceous shale deposits. The shales had been deformed and twisted by the same convergent forces that had lifted the nearby Rocky Mountains, but erosion had smoothed off the sharp edges. The land was semiarid and treeless. More verdant lands could be seen in the distance as we looked westward towards the Rocky Mountains and Waterton-Glacier International Peace Park. Glacier National Park was our next destination.
Chief Mountain was especially prominent on the western horizon. The peak is an outlier of the Rocky Mountains, an isolated upper plate of a thrust fault that had pushed the hard Paleozoic limestones over the softer Cretaceous rock. Erosion had then isolated Chief Mountain as a klippe (see the diagram below).

The mountain was a dramatic welcome back into the United States. We only had a few more days left on our journey, but there was still much to be seen. The story will continue in another post!

Monday, October 20, 2014

"Head Smashed In"... um, sounds like a great place to visit...

The High Plains have their quiet times. Sure, there are the vicious winter storms,  the days when the wind blows hard, and the summer thunderstorms. But other times the wind may be just a light breeze through the grass, maybe a hawk soaring overhead. Or a huge marmot standing guard on a sandstone outcrop. But I can also stand in this place and imagine a similar quiet day a few thousand years ago. It's quiet, but then the ground starts to tremble, and a dust cloud rises over the crest of the low hill. The birds startle and take flight, the marmot dashes for cover, and suddenly over the ridge comes a thundering herd of buffalo. They're stampeding, and the leading animals start to shift directions, but then suddenly a strange figure jumps up, yelling and waving limbs. It might be a wolf, it's hard to tell in the panic, so the herd shifts direction once more. The leaders now realize they are headed for a precipice and they try to stop, but it's too late. They go over the edge, pushed by the animals behind. They impact on the rocks and bones below, most of them dead immediately. In a moment it is over. People emerge from their hiding places and start to butcher and process the meat, bones and hides. It has been a successful hunt and they will have enough food and furs to make it through the difficult winter.
There is a seven story building in this picture. Can you see it?
The First Nations people of Canada and Native Americans of the High Plains depended on the buffalo for survival. They made use of the meat, the fat, the bones, and the hides. But anyone who has ever seen one of these immense animals knows that they would a dangerous adversary in a hunt. They can be as long as eleven feet and weigh a up to a ton. They can easily outrun a human, capable of speeds of 35 miles per hour. Though it was done, bringing one down was a difficult and dangerous proposition.
We were in southern Alberta on our Northern Convergence tour of western Canada, and were making our last stop in the country at Head Smashed In Buffalo Jump World Heritage Site. At Head Smashed In and similar localities, the geology provided a safer way to hunt the animals.
At the edge of the prairies where the mountains rise from the plains, the land is not so flat as it is further east. The convergence far to the west compressed and pushed up the Rocky Mountains. The soft Cretaceous mudstones and sandstones underlying the high plains were also pushed up into broad swales and low hills. Ice, water, and wind exploited fractures in the rock, and erosion ate away at the edges of the hills, exposing vertical cliffs of sandstone. Just such a cliff is exposed in the Porcupine Hills outside of Fort Macleod, Alberta. For at least the last 5,800 years, people have utilized the cliff here to capture and kill buffalo.
A spring emerged from the base of the cliff, providing water at the kill site (the green watercourse is visible in the picture above). The Old Man River flows in the flats below, providing sheltered sites for villages.
Tipis have become such a stereotype that some might think that most Native Americans lived in them. I groan inwardly whenever I see one at "Indian Stores" or southwest tourist traps. But the tipi at Head Smashed In was an appropriate sight. The tipis were an excellent shelter on the windy plains. They were portable, an important consideration for a nomadic people. I know of paleontologists in the region who tried to camp in modern nylon tents, but gave them up for tipis, which were more comfortable and more durable in windstorms.
The site was declared a World Heritage Site in 1981 for its archaeological value. Excavations 39 feet deep in the cliff show a complex history of buffalo hunting going back 5,800 years (two spear points show activity in the area as far back as 9,000 years. The visitor center was constructed to blend in to the landscape, and does so admirably (see the picture above). There are trails to the top of the cliff where some cairns from the hunts can still be found. A trail also loops around the base of the cliff. One of the nice surprises inside the well-designed center was a hallway lined with numerous paintings and artwork by First Nation students representing the oral histories of their culture.

About the name of the place. In the Blackfoot language it is called Estipah-skikikini-kots. Legend has it that a young man decided to watch one of the buffalo hunts from the base of the cliff. He picked a bad spot, and was crushed beneath the weight of the falling animals. The name doesn't exactly inspire confidence in the site as a destination when traveling in the region, but it is indeed a fascinating place to visit. It's full of history, but it is also a place of wide-ranging views and scenic beauty, and despite the name, serenity.

Sunday, October 19, 2014

The Sierra Nevada Underground: How does a newly discovered pristine cave look? Finding out at Black Chasm

There are caves and there are caves. Many of them were discovered long ago, and the easily accessible ones suffered grievous damage. In earlier days, cave decorations (speleothems) were broken off as souvenirs in the sadly mistaken belief that they would grow back quickly. Today's cave vandals have no such excuse. They break and destroy for sheer maliciousness. It's sad either way because caves don't recover, not in any kind of human time-frame. Their special kind of beauty is lost to us.
That's what makes a few caves extra precious. A few weeks ago, I explored Crystal Cave in Sequoia, which by virtue of being in a national park and being discovered by park personnel, was protected before catastrophic damage was done. It was developed for tourism, and millions of people have walked its passageways and yet it was protected by and large from the worst abuses.
The tour I was on yesterday was a different circumstance. Black Chasm cave near the Gold Rush town of Volcano in the Sierra Nevada Mother Lode is a privately owned cavern. It was discovered in the 1800s but the "chasm", a ninety foot deep crevice, prevented the miners from ever getting into the remote reaches of the cave. Access required technical climbing skills, and people who go through that much trouble rarely have vandalism in mind.
A decision was reached in the 1990s to develop the cave for tourism, making a total of six such caves in the Sierra Nevada: Crystal Cave, Boyden Cavern, Mercer Caverns, Moaning Cavern, California Cavern, and Black Chasm. A stairwell and boardwalk were pinned to the edge of the chasm, allowing for access to the nicely decorated room beyond. A room never despoiled by vandals, or dirtied by sooty lanterns and torches.
For those who have only seen the usual soiled yellow-brown stalactites and stalagmites, the pearly white formations are a revelation about what a cave can look like. Beautiful examples festoon the walls. But Black Chasm has an additional feature that is astounding. Stalactites on LSD!
Growing out of the walls at odd angles, and growing in totally random orientations, helictites are strange and rare cave formations. They are easily broken off, and are undoubtedly one of the first formations to disappear from caves. They are present in Black Chasm in, shall we say, large numbers. Really large numbers, enough that the cavern was granted National Natural Landmark status, a federal designation that recognizes the value of natural features on private lands, including agreements to protect the resource.
The exact process by which helictites form is not clearly known. They are most likely related to capillary action of water squeezing out of microscopic openings in small stalactites and precipitating small amounts of calcite. Because water under pressure can be squeezed upwards, the development of the helictites is not governed by gravity.
The number and variety of helictites in the Landmark Room of Black Chasm is simply stunning. I haven't been to every cave in the world, but I would not be surprised if these are some of finest examples in existence (although I am always open to correction on such issues).
Black Chasm Cave, as noted before, is a privately owned business. They are there to make a profit, but they have done a good job of protecting their cave, and I recommend a visit. They offer discounts for educational groups (they can accommodate up to 22 people at a time, so large classes would need to split into two tours). More information about the cave can be found here. Tell them Geotripper sent you!

Friday, October 17, 2014

Northern Convergence: Tragedy at Crowsnest Pass

Frank was a coal mining town of around 600 people in 1903. The coal seam ran along the base of Turtle Mountain, so the town was established there as well. The Canadian Pacific Railway also crossed the area on its way to Crowsnest Pass.

The local First Nation people did not like Turtle Mountain. They called it the "Mountain that Moves", and refused to camp in the area. The Europeans had no such worries, and mining of the coal was well underway. In the early morning of April 29, 1903, a shift of 17 miners was working deep underground. For weeks there had been strange things happening in the mine. Timbers holding up the tunnel walls would splinter and break for no apparent reason. Coal would occasional "mine itself", crumbling out of the seams overnight when no one was around. Small earthquakes were occasionally felt underground. The miners knew that the collapse of mine tunnels was an ever-present danger, so they may not have been overly surprised to hear the explosive concussion followed by an ominous silence. They were trapped, no doubt by a cave-in. They began to assess their situation. Soon, water was pouring into the tunnels, making a bad situation even worse.

The normal passage to the surface was blocked, but one of the miners knew that a second coal seam might be close enough to the surface that they could hack their way out. They started digging for all they were worth, gasping in the increasingly toxic air. One by one, the miners gave out. They weren't dead, but they just did not have the energy to pick up their tools. Only three of them were still working when they broke through to the surface. Rocks were still falling from above, so they couldn't yet escape, but they had fresh air, and they quickly cut another opening beneath a protective overhang. After thirteen horrible hours they emerged at the surface to find their experience was only a part of an even larger tragedy. A gigantic avalanche had buried part of their town, killing between 70 and 90 people. The miners had been given up for dead, so their appearance was some small bit of good news in the midst of the horrific event.
It gets to a certain point when driving through the mountain wilds of British Columbia and Alberta that one expects that trees will be growing just about everywhere. The region has plenty of precipitation through the year so things will be green. Approaching Crowsnest Pass during our recent Northern Convergence tour, we were struck by the sudden appearance of an absolutely barren slope. It doesn't take long to realize why, as the highway crossed a huge debris field covered with gigantic boulders. It was the debris avalanche that destroyed so much of Frank back in 1903.

The slide was truly epic in scale. Totaling 30 million cubic meters (82 million tons), the avalanche was 1,000 meters (3,300 ft) wide, 425 meters (1,394 ft) high and 150 meters (490 ft) deep. It spread laterally over level ground, covering three square kilometers. The rocks had flowed over the surface like a thick liquid at speeds of up to 70 mph (112 km/hr). The entire event was over in less than 2 minutes.
 The slide was probably inevitable. The limestone layers had been folded into a huge anticline (upward pointing fold) with thrust faults at the base, on top of weak Cretaceous sediments. Glaciation had oversteepened the flanks of the mountain. Fissures sliced deep into the rocks allowing water and ice to accumulate, weakening and wedging the rocks apart. The mining at the base of the slope was quite possibly a contributing factor.
The Frank Slide was the worst mass-wasting disaster in Canadian history. But life went on. The mines were reopened (a horse who worked in the mine was actually found alive after a month underground). The town grew even larger for a few years, but by 1917 the coal mines closed down. Today about 200 people live in the village nearby, and an interpretive center has been constructed that provides information on the extraordinary event.

We headed into nearby Pincher Creek for the night. It was our last night in Canada, but we still had plenty yet to see, on both sides of the border..


Wednesday, October 15, 2014

Northern Convergence: We'll Call it "Rock": The Okotok Erratic

There is a big rock out on the high prairie near Calgary, Alberta. That all by itself is a bit of strangeness. It's even more strange because it is around a hundred miles (160 km) from the cliff in which it originated, up in the Rocky Mountains in Jasper National Park. The Blackfoot Indians had a creative name for the rock, Okatok, which in their language means, um, "rock". These names always sound better in the original language! For whatever reason, the spelling changed a bit to Okotok.
The Blackfoot people had a great story for how the rock got to this spot, a myth that could have served as the inspiration for the rock monster in the movie "Galaxy Quest". Their legendary trickster Napi was resting on the rock on a hot day, so he left his cloak on the rock, saying "Here, I give you my robe, because you are poor and have let me rest on you. Keep it always". Murphy's Law dictates that it soon got cold, and the rain began, so Napi asked for the return of his robe. The rock refused so Napi grabbed "his" cloak. In a moment, the rock was up and running after him! Napi called on his animal friends, the Bison, Antelope and Deer, and none of them could stop the gigantic rock. When all seemed lost, a bat flew straight at the rock, collided with it, and the rock was split in two! The bat had saved Napi, and got a squashed face for all his trouble (such things have to be explained somehow...).*
A smaller erratic a few hundred yards from the Okotok Erratic
The geologists tell a different story, and were it not for the overwhelming evidence it would seem just as fantastical. During the Pleistocene Ice Ages, the continental ice sheets covered all of the region thousands of feet deep. Up in the Rockies at Jasper a huge rock slide dumped massive boulders onto the surface of the glaciers emanating from the high peaks. The glaciers flowed eastward onto the High Plains, eventually meeting up with the vast ice sheet that originated near Hudson Bay. The two ice sheets didn't mix, so the two "rivers" of ice flowed together towards the south. The gigantic rocks from the cliff in Jasper were dumped in a line many miles long where the glaciers moved together. These isolated boulders are called glacial erratics.
The rock is sometimes claimed as the largest erratic boulder in the world, but I have no way to evaluate the claim. It certainly is huge, and worthy of a visit (it is a few miles southwest of Calgary). The Blackfoot or other First Nation peoples were certainly impressed. Faint pictographs can still be seen on the flanks of the rock.
Pictographs are symbols painted on the rock. Petroglyphs are chipped into the rock.

This is a continuation of our Northern Convergence tour of British Columbia and Alberta. In this case, I guess "convergence" refers to the two masses of glacial ice. We concluded our visit and headed back towards the Rocky Mountains and Crowsnest Pass to check out a not-so-long-ago tragedy. More on that next time.

*The Blackfoot legend is  loosely rephrased from interpretive signs at the park.

Tuesday, October 14, 2014

For Modesto Area Friends: Celebrating the Art of Science at the Science Community Center of MJC, Oct. 15, 2:00PM

If you are in the Modesto region, you are invited to a reception for the artists of the Science Community Center. We have a number of interesting works that are being celebrated tomorrow at 2:00 PM. I would love to run in to some of you!

I didn't sculpt anything, but I have a number of my bird photographs mounted on the walls in some of the meeting rooms. I've been exploring the rather diverse population of native birds who inhabit the wilder corners of our campus, and discovered some three dozen species so far and counting. You can see a lot of them at Geotripper's California Birds.