Travels in Cascadia: Threading the Needle on Hurricane Ridge

Leading a field studies trip is a stress-filled enterprise. There are the big things to worry about: auto accidents, injuries, conflicts with law enforcement, lost reservations, and those sorts of things. But those thankfully don't happen much. But weather does happen, and field studies trips tend to be tightly scripted affairs with not much room for weather-related complications. Yet they happen, especially on trips in the Pacific Northwest. We've had trips where we had just the one chance to see Mt. St. Helens, and it was completely fogged in. There was the one chance to see the Sea to Sky Highway in British Columbia, and it was raining the entire way. We've missed a lot.

This year was going to be different. We worked some flexibility into the schedule, spending two nights each at most of our localities, giving us the chance to postpone a particular plan for a day to allow the weather to clear up. But on our second day out, I was worried. Ever since the longest ten-day forecast, a storm was brewing out in the Pacific Ocean, one that was arriving in waves over several days. We had given ourselves two days on the Olympic Peninsula, and rain was falling on Hurricane Ridge the first day, so we elected to go to Neah Bay and Cape Flattery instead. But that left us just one more chance to have a clear view at Hurricane Ridge in Olympic National Park. The sunrise (above) was not promising. According to the forecast, we would have a brief window of maybe three or four hours before the storm closed in, but we drove through light showers on the road up to the ridge.

My concern grew as we continued up the road, rising from sea level to over 5,000 feet. The far ridges would appear for a moment and then become obscured, and I didn't know until we reached the top ridge if we would actually see anything...

… but we did! And no matter how many times I've been on Hurricane Ridge, nothing quite prepares me for the view from the end of the paved road. It is simply astonishing. As we emerged from the vehicles I felt the stress falling away, like dropping a particularly heavy load from my shoulders. We gathered the group and said a few words about the geology. We would save the longer presentations for later in the day down the hill. With an impending storm, I didn't want our students to miss any of the dramatic scenery. And it is dramatic.

The Olympic Mountains rise from sea level to nearly 8,000 feet and are extremely rugged. They capture prodigious amounts of rain and snow on the western flanks, so much so that temperate rainforests coat the western slopes. It was a nightmare for geologists who were trying to unravel the geologic history.

The mountains exist because of subduction. For most of 200 million years a convergent boundary has been active in the region, as the crust of the Pacific Ocean basin has been sinking against the edge of the North American Continent. In some places, like California, the subduction zone has been replaced by a transform boundary (the San Andreas fault). But in Northern California, Oregon, Washington, and part of British Columbia, the subduction zone is still active, still producing earthquakes, and still raising mountains. It's called the Cascadia Subduction Zone (from hence comes the name of this series).

Source: Geological Society of America

In a "normal" subduction zone, there are four parts: the trench, an accretionary wedge, a forearc basin, and a magmatic arc. The trench is the deepest part of the ocean floor where the oceanic crust sinks back into the mantle. The accretionary wedge is a collection of seafloor sediments and crust that has been scraped off the subducting plate and added to the edge of the continent. The forearc basin is a shallow sea that may develop inland of the accretionary wedge (California's Great Valley originated in this fashion). The magmatic arc is a system of volcanoes and intrusive plutons resulting from the melting of rocks in the lower crust and upper mantle above the descending slab (water released from the slab lowers the melting point of the rock, leading to the formation of the molten rock).

Looking at the thickly forested slopes below Hurricane Ridge, I cannot envy the geologists who originally mapped the Olympic Mountains. Simply finding an exposure of rock must have been challenging at times. What these geologists did was to take the rare rock exposures and extrapolate them into a semi-coherent map that reveals the structure of the Olympic Mountains. They did the equivalent of taking a few pieces of a jigsaw puzzle, putting them in the right location relative to the others, and then drawing in the remainder of the puzzle from scratch. I've been way too spoiled by the naked rock exposures of places like Death Valley and the Mojave Desert!

The geologic map reveals the basic structure of the Olympics. A "horseshoe" of basalt and sedimentary rocks (the Peripheral Rocks, or Crescent Formation) partially surrounds the "Core Rocks", an assemblage of lightly metamorphosed sandstone and shale layers. The Core Rocks are characteristic of the types of deposits that form from underwater landslides ("turbidity currents") within the trench and accretionary wedge of a subduction zone. The fact that these rocks are now thousands of feet above sea level is the interesting conundrum. Accretionary wedges are generally below sea level, or exist as small islands. They can be pushed higher. For instance, the rocks of the Cascadia accretionary wedge are exposed in the Coast Ranges of  Washington, Oregon and California, but nowhere are the exposures as spectacular as the Olympic Mountains.

Convergent boundaries can be exceedingly complex places. Bits and pieces of continents and island arcs may randomly arrive at the subduction zone, mucking up the subduction process the way too many sheets of paper at once can muck up a paper-shredder. In the case of the Olympics, there was a mass of land north (Vancouver Island) and an accreted terrane to the south (the North Cascades), and a bend in the subduction zone itself. In essence, too much material was being stuffed into the subduction zone, so the excess material went the only way it could, which was up. The mountains have been rising for around 15 million years. They would be higher, but the incredible amount of precipitation tears the mountains down at a roughly equivalent rate.

Pillow basalt from the subducted oceanic crust is exposed along the Hurricane Ridge Road and along trails near the viewpoint. When we went down the road later on, we found that a small rockfall had dumped some of the pillows onto our highway. So, as it turned out, we managed to miss having rocks fall on our vans, i.e., one of the hazards I mentioned at the start of the post!

We could easily observe the glaciers that scour the upper reaches of the mountains. Glaciers technically shouldn't exist here. Although we were at a high enough latitude, the nearby Pacific Ocean moderates the climate, keeping things warmer than they would otherwise be (the Olympics are at the same latitude as Great Falls, Montana, or St. Paul, Minnesota). But temperature isn't the only factor in glacier development. The sheer amount of snowfall in combination with temperatures that are just cold enough allows glaciers to exist at these unusually low elevations.

We had a good introduction to the basic features of alpine glaciation as we gazed across the valley to Mt. Olympus. There were horns, aretes, and cirques as well. Glaciers were going to be a big part of the story of British Columbia, and Hurricane Ridge provided a spectacular setting for the first discussion of how they worked.

It was nearly noon and the storm clouds were building. We were rained on as we descended back down to the lowlands. It was time to prepare for the ferry ride across the Strait of Juan de Fuca to Vancouver Island.

The Hawai'i That Was: Mauna O Wakea, the Opening to the Heavens, and the Realm of Ice

It's hard for me as a person of European descent to imagine what the first Polynesians to arrive at the islands thought of Hawaii's highest mountain. Mauna Kea, the "White Mountain", or Mauna O Wakea, the mountain of the god Wakea, the "expanse of the sky", rises to a height of 13,802 feet (4,207 meters), just slightly higher than its more massive neighbor Mauna Loa (13,679 feet; 4,169 meters). It's a reasonable assumption (spoken here by the amateur) that the first people to arrive had no cultural memories of erupting volcanoes, but even more to the point, no cultural memories of ice. But ice is what they found on Mauna Kea and Mauna Loa.

A mountain nearly 14,000 feet high casts a very long shadow (2009)

Wait a moment. Ice? Snow? In Hawai'i? It's true that the islands are in the tropics, but altitude makes up for a lot where snow and ice are concerned. In other parts of the world near the equator, for instance the Andes and the Himalayas, glaciers and snow are not unusual. But none of the other islands of Polynesia approach an elevation anywhere close to that of Mauna Loa and Mauna Kea (along with Haleakala on the island of Maui). Snow often falls in winter, and storms in summer sometimes leave ice on the summit (the snow patches in picture below are from June of 2009). During the ice ages, Mauna Kea was even covered by glaciers! During at least two periods, between 70,000 and 150,000 years ago, and from 10,000 to 40,000 years ago, glacial ice covered about 28 square miles of the mountain's summit. Lava flows that were quenched by the ice produced an unusually hard basaltic rock that was prized by Native Hawaiians for tool-making in the years before iron arrived on the islands, carried by Europeans ships.

The Polynesians may have had their origins in New Guinea or Taiwan, but something more than a thousand years may have separated the native Hawaiians from any ancestors who ever laid eyes on snow-covered mountains. This was something new for them. The strange landscape of Mauna Kea soon became to them a holy place, a spot that was the origin of all people as a result of the relationship of the gods Wakea (the aforementioned "expanse of the sky") and Papahānaumoku (the Earth mother, or "she who gave birth to the islands"). Many on the islands continue their traditions of worship on the mountain (below).

An altar near Pu'u Huluhulu at Saddle Road Summit, just south of Mauna Kea.

And that's where the conflict starts. Wakea is the god of the "expanse of the heavens", and the summit of Mauna Kea certainly offers what may be the world's best view of the heavens, due to the high elevation (over more than 40% of the atmosphere), very low air turbulence, lack of light pollution, and the extremely clean dry air, far from any sources of pollution. The relatively gentle slopes provide for vehicular access. Since 1970, 13 state-of-the-art observatories have been constructed on the summit of Mauna Kea. The fourteenth observatory was supposed to begin construction last year, but massive protests and a legal suit have postponed any further building for the time being.

It's a conundrum. The argument isn't simply a religion versus science debate. There are concerns about the effect of the project on the ecosystems of the mountain, as well as the movement of groundwater. A great many endemic and endangered species cling to existence on the upper slopes of the mountain. Some of those who are invested in the sacred aspects of the debate don't actually oppose the telescope, seeing a relationship between a god who represents "the expanse of the skies" with the new-found ability of humans to see farther into the cosmos using the technology that we have created. Others most certainly see the construction of yet another observatory (and the biggest one yet, with a larger "footprint") as a desecration of sacred ground. Imagine, perhaps, building a group of telescopes on the summit of Mount Sinai. There might be good scientific reasons for choosing the site, but it wouldn't sit well with those of the Jewish, Christian and Islamic faiths.

Mauna Kea has been erupting for perhaps 1,000,000 years, but it is hard to say, since younger flows have covered the older ones. The volcano is presently dormant, with no eruptions any time within the last 4,500 years. That doesn't mean it is dead. A new eruption at the summit could certainly make any discussions concerning telescope-building moot (although some would consider it a statement from Wakea).

We saw Mauna Kea from several directions during our recent exploration of the island. It greeted on clear mornings from our hotel in Hilo (above), and we had a spectacular view of the mountain from the upper slopes of Kohala, another long-dormant shield on the north end of the Big Island (below). One evening we drove to the Onizuka Center for International Astronomy at the 9,000 foot level of the mountain for a star-viewing (these are held nightly). The skies are truly pristine, and our students saw the constellation of the Southern Cross for the first time in their lives (it of course lies hidden beneath the horizon in our more northerly climes).

Three major shield volcanoes on the Big Island, as seen from a fourth. We are standing on Kohala, looking at Mauna Kea (left), Mauna Loa (mostly hidden by clouds in the center), and Hualalai (right).

This post is part of a blog series on the Hawai'i That Was, an exploration of the pre-human, and pre-European history of the Hawaiian Islands, which was the objective of the field course we conducted a few weeks ago. In the next post, we will move on from Hilo and the active volcanoes and have a look at the Kona Coast.

The Southern Cross is the kite-shaped group of stars on the left side of the photo. Taken from the patio at the Onizuka Center for International Astronomy

Vagabonding on Dangerous Ground: Controversial Stone People, Fire and Ice, and an Olympic Legacy

A stone person stands on an outcrop up in Callaghan Creek a few kilometers west of Whistler in British Columbia. It has been called an inuksuk, although inunnguaq may be the more proper name (it's the difference between "something which acts for or performs the function of a person" and "imitation of a person"). The far north can be a featureless landscape with little in the way of landmarks, so the First Nation people like the Inuit used stone cairns for navigation and travel routes, and as signs for fishing sites, camps, hunting grounds, or places of spiritual importance. It is unclear if the human forms, the inunnguat (the plural form of the word), were used much prior to European colonization.

We were in Whistler, British Columbia, on our recent vagabonding adventure through the lands influenced by the Cascadia Subduction Zone, a place you may remember as the site of the 2010 Winter Olympics. Reminders were all over the place, including the rings and stage in the center of town. The slopes are covered with ski runs, and the highway from the coast, which we mentioned in a previous post, was widened and straightened, despite the ongoing threat of mass wasting.

The inunnguaq stood at the entrance to the Olympic venue in Callaghan Creek where the ski jump and biathlon events were held, and indeed, an inunnguaq was used as the symbol for the games in general. Now, I've loved the symbolism of the inunnguaq, and lots of my souvenirs of Canada include the image. But I've come to understand that it was of some concern to the First Nations people of Canada. It could be considered a sign of respect for the original people of Canada, but it could also be interpreted as a bit of cultural appropriation.

Some noted that the actual historical inuksuit (plural) rarely if ever took a human form. That practice may have not begun, as noted above, until European colonization. Others argued that the inuksuit were used by arctic First Nation peoples, whose lands were hundreds, even thousands of miles away from the Olympics site. I can see this as being the same as using a tepee as a symbol for the Los Angeles Olympics even though tepees were used by nations on the Great Plains, a thousand miles or more away. It's conceivable that a better symbol might have been a Thunderbird, a cultural icon of the Coast Salish people, especially since two prominent volcanic peaks in the Whistler area were seen as the perch for the animal (the Black Tusk, and Mt. Cayley, discussed below). Now, I'm no sociologist or anthropologist, and I certainly don't live in the region, so I'd love to hear some perspectives from those who are close to the issue.

But I loved seeing the ski jump! I've never seen one before in person, and I can say without any doubt whatsoever that you will never see me wearing skis on something like this. It is steeper than it looks, and I grew up watching that iconic crash from ABC's Wide World of Sports (the "agony of defeat"). It's still in use for training, but obviously not this time of year.

I would love to say that I fully research the landscapes that I explore beforehand, but this was vagabonding. I didn't know, other than a vague goal of reaching Canada, that we would make it as far as Whistler, and so I didn't look into the geology of Callaghan Creek where the Olympic venue was located. It turns out that the reach of Cascadia is more than I realized. There are several lesser-known, but potentially active volcanic centers to the north of Garibaldi. These include the Bridge River Cones, Mt. Meager, possible the Silverthrone Caldera, and across the valley from me at that moment, the Mt. Cayley Volcanic Field.

Source: "Garibaldi Volcanic Belt-en" by © Sémhur / Wikimedia Commons. Licensed under FAL via Commons - https://commons.wikimedia.org/wiki/File:Garibaldi_Volcanic_Belt-en.svg#/media/File:Garibaldi_Volcanic_Belt-en.svg

The main peaks of the volcanic field were hidden in the clouds (now there's a Pacific Northwest surprise), but we could see some of the glaciers that have formed on the flanks. The Mt. Cayley field has not erupted in some time, maybe 200,000 years, but hot springs and earthquake activity indicate the presence of magma beneath the complex. The Mt. Meagher field to the north erupted just 2,400 years ago.

The glacier between Metal Dome and Brandywine Mountain shows the state of the drought conditions this year and the ongoing loss of glacial ice in general from global warming. It was July, a time when a fair amount of snow should still cling to the peaks, but most of the ice visible is a dirty gray color. The gray is the old glacier ice, no longer hidden and protected by an insulating blanket of white snow. So the melting that is taking place is from the glacier itself, and these glaciers have been receding at an accelerating pace for decades now.

There weren't a lot of flowers out and about, but there were some beautiful ones here and there. No, I don't know many flower names. I'm a geologist, after all. They cover rocks.

There are a number of wonderful waterfalls in the area, the delightful results of volcanism and glaciation. Alexander Falls are just off the road in the Callaghan Valley downstream of the Olympic park.

Brandywine Falls are on the main Sea to Sky highway at Brandywine Falls Provincial Park. The 70 meter (200 foot) waterfall flows over the lip of a basalt lava outcrop. The falls are migrating upstream. The rock beneath the lip of the falls is softer and more easily eroded, so it is constantly wearing away and undercutting the cliff. Niagara Falls is migrating in the same manner.

We continued down the Sea to Sky Highway (Sky to Sea?), and saw some more incredible geology. It's coming in the next post...

The Looming Volcanic Giant of Northern California: Mt. Shasta

So California is all about earthquakes, right? Oklahoma has tornadoes, Florida has hurricanes, Minnesota has blizzards,and California has the San Andreas fault (and all the other active faults that no one seems to remember the names of). But really, California has a "little" of everything, and we have a "big" of volcanoes. I was on my way home today from family Thanksgiving celebrations in Oregon, and while we traveled down Interstate 5, we had some simply awesome views of California's gigantic volcano, Mount Shasta.

Shasta is the second tallest volcano in the Cascades Range at 14,179 feet (4,322 m) after Mt. Rainier, but in bulk it is the largest composite cone/stratovolcano in the range (Medicine Lake Highland, also in California, has more volume, but is a shield volcano that doesn't even reach 8,000 feet in elevation). The mountain is composed largely of andesitic lava flows and ash deposits, but also includes outpourings of basalt and dacite. It has been active for more than half a million years, and may have last erupted in 1786. It has had eruptions on average every 600 years or so, making it the second most active volcano in the Cascades after Mt. St. Helens.

Shasta is a composite cone in the truest sense. At least five distinct volcanoes in various stages of disrepair make up the mountain. The earliest collapsed around 350,000 years in a gigantic debris avalanche that flowed 28 miles north to the vicinity of Yreka (the nature of the slide was not recognized until the 1980s after St. Helens produced a similar avalanche with a length of 12 miles). The Sargents Ridge and the Misery Hill cones erupted, became dormant and were deeply eroded by glacial activity. Shastina erupted around 9,800 years ago forming a large satellite cone that is actually the third highest volcano in the Cascades. Hotlum Cone is the currently active volcanic center, having erupted fairly often during the last 9,000 years.

Shasta has seven active glaciers, including the longest and most voluminous in California. Meltwater from the glaciers will occasionally cause destructive lahars or volcanic mudflows. Other dangers lurk on the flanks of the volcano, where some 20,000 people live. Ash flows, lava flows and even a caldera collapse are possible hazards to those who live in the shadow of the mountain.

The mountain is famous for mythology and legends as well. The native Americans certainly understood the power of the mountain, having witnessed some of her eruptions. The prominence of the giant edifice has resulted in all manner of speculation about the gods and aliens who call the mountain home. Many consider the mountain to be a "global power center" or "spiritual energy vortex". The existence of the mountain alone makes it magical for me, but folks seem to take this stuff seriously. I was in a crystal shop this afternoon listening to a strange and earnest conversation about chemtrails and spiritual vibrations. Books abound about the Lemurians and other societies that live inside the volcano. They've got it all figured out...

Shasta is a beautiful mountain, and a looming volcano that is capable of creating havoc. On this particular day, all was peaceful and serene. We enjoyed the sight during our long journey.

A Convergence of Wonders, Day 7: Of Time and Pressure in Glacier National Park

There is a movie quote that I've always appreciated, from a movie with a several surprising references to geology, The Shawshank Redemption:

All they found of him was a muddy set of prison clothes, a bar of soap, and an old rock hammer, damn near worn down to the nub. I remember thinking it would take a man six hundred years to tunnel through the wall with it. Old Andy did it in less than twenty. Oh, Andy loved geology. I imagine it appealed to his meticulous nature. An ice age here, million years of mountain building there. Geology is the study of pressure and time. That's all it takes really, pressure, and time.

Time and pressure is the story of Glacier National Park. There are the glaciers, of course, for a while more, maybe twenty years, but there are also the rocks, and there are the mountains too. Glacier National Park in northern Montana has some of the most incredible scenery of any national park but it has a fascinating geological story as well.
I mentioned at the beginning of this mini-blog series that an overall theme was convergence, due to the influence of the subduction zone that has existed off the west coast of the U.S. for several hundred million years. It is not unusual to see the effects of subduction for eighty miles or so inland where stratovolcanoes like those of the Cascades develop. But we had been traveling east now for more than five hundred miles. How could a subduction zone influence the crust so far inland?

Before we could find out, we needed to decide whether or not to make a run for the border. Glacier National Park is actually properly called Waterton-Glacier International Peace Park, as it shares a boundary with Waterton National Park in Alberta, Canada. You can drive to the border as we did here, or you can backpack through the park (and still go through customs, apparently).

We bravely set foot into the wild frontier of Canada, and also wondered who has the job of keeping that line clear through the miles of forest. It was one of the busiest border crossings I've ever seen, as there was at least one motorcycle that came through while we hung around.

Lots of flowers were out and about. Since we missed Logan Pass and the Going to the Sun Highway and the fields of glacier lilies often found there, I was glad to find a few along the highway near the border.

We reached a vista point for looking at Chief Mountain (9,080 ft; 2,768 m), one of the truly unique peaks in the region. Click on the panorama shot below to see just how isolated the mountain is. It is an eastern outlier of the Rocky Mountains, standing some 5,000 feet above the Great Plains. It is visible for miles, and is a sacred place to the local Native Americans. Half of the mountain lies within the boundaries of the Blackfeet Reservation, and the Blackfeet people claim jurisdiction over the entire region (a fact that I learned, admirably, from the visitor center for Glacier National Park).

I was briefly distracted by some beautiful Shooting Stars...

The unique shape of the mountain derives from its origin as a fault klippe, an erosional remnant of a thrust fault . It is one of the world's best examples of this type of feature. The rocks forming the plateau and summit are actually older than the softer Cretaceous sedimentary rocks below. The older rocks were pushed upwards from deep in the crust and then pushed over the younger rocks by intense compressional forces.

I wish I had a chalkboard to illustrate, but the wikipedia diagram will have to suffice in this instance!

From Wikipedia (http://en.wikipedia.org/wiki/File:Thrust_system_en.jpg)

Where did these compressional forces come from? Apparently, the subducting slab from way out west in Washington got trapped along the base of the crust and never plunged into the mantle until it was far inland. This caused a crumpling of the crust in late Cretaceous and early Cenozoic time (between about 100 and 50 million years), a series of related mountain-building events called the Sevier and Laramide Orogenies. At Glacier National Park, the fault zone is called the Lewis Thrust.

We then drove to Upper St. Mary Lake, for a look at the unique rocks of Glacier National Park (and one of the most iconic views in the national park system at Wild Goose Island Overlook, below). All of the rocks visible in the picture below are more than a billion years old, and sit on top of the much younger Cretaceous sedimentary rocks. This is another manifestation of the Lewis Overthrust that we first saw at Chief Mountain.

The glacial features are outstanding: U-shaped valleys, hanging valleys, truncated spurs, aretes, horns, cirques, moraine lakes, and the occasional surviving active glacier. The park once had around 150 glaciers. Today there are no more than 25. They are expected to be gone within twenty years. Ignorant politicians should be forced to stand at the base of one of these disappearing glaciers when they pontificate about how global warming is a hoax. They shouldn't hide in places like drought-stricken Oklahoma (where coincidentally they shouldn't be allowed to fly airplanes).

Picture by Susan Hayes

The slightly dipping layers making up much of the park are a series of sedimentary rocks called the Belt Supergroup. The rocks were deposited in fault-controlled basins at the edge of the ancestral North American continent over a billion years ago. It was a strange time in Earth history...no plants, no animals, just barren rock on land, and only bacteria and other single-celled organisms in the lakes and oceans. The only real fossils are layered mounds called stromatolites.

One of the most vivid layers was the dark red Grinnell Formation. There was no oxygen in the Earth's original atmosphere, but when photosynthesis evolved, oxygen was released. It immediately reacted with iron in the sediments, and the world turned rusty red. Although the rocks are from an alien time in our own history, they still contain recognizable features like the exquisitely preserved mudcracks seen below.

The group was fascinated by the outcrop (always a pleasing moment for a teacher, especially seven days into a trip!).

The group had the afternoon off, and most took off on hikes (and saw grizzlies and bighorn sheep). Others found a wi-fi signal in the wilderness, and did some homework (along with some laundry)...times have changed in the world of field-tripping!

I had a few moments in the late afternoon, so I went moose and grizzly hunting around the outlet of Upper St. Mary Lake. The rivers were swollen with snowmelt (flooding is still a problem across the northern tier of states). I didn't find any animals, but they no doubt noticed me crashing through the brush.

It was a beautiful evening, and I had a fine time photographing the lovely clouds that swirled above us. I realized with a start that we had reached the half-way point of our trip, and that the moment we turned our backs on the Canadian border, we were turning towards home. There were many wonders yet to come, though. Tomorrow we would cross part of the Great Plains, and make our way to Bozeman through the lands once trod by the dinosaurs.

Time and pressure....