Volcanoes in the Mist (and underground): Travels in Death Valley

The Inyo Mountains, in any other setting in the world, would be considered a major mountain range, preserved as a national park perhaps, and celebrated as scenic wonderland. But just like an accomplished sibling overshadowed by a more famous brother or sister, the Inyos lie across the valley from the most spectacular part of the Sierra Nevada, and south of the higher White Mountains. For better or worse (mostly better), only a few roads penetrate the range, including the main western highway into Death Valley National Park, State Route 190. That was the road we followed on our recent exploration of Death Valley.

As was noted in the previous post, we attempted our trip during the Bombogenesis storm that wreaked havoc across Southern California. This kind of storm can often result in disaster as highways get closed or damaged by landslides, but we were lucky and were able cross the Inyo Mountains and Darwin Plateau without problems. But we did get the opportunity to see some great geology, and even were able to add a new stop to our itinerary (because we missed a different one, but I'm not complaining).

Our first sight as we approached the mountains was the snow covering the desert peaks (first picture above), a hint to the seriousness of the storm we were challenging. The tilted rocks are Paleozoic-aged (300-550 million years) limestone layers. They recall a time when California was very different, completely submerged under a shallow tropical sea. We would be seeing more of these fascinating rocks later on. The road crossed the flat uplands of the Darwin Plateau, and then plunged down a steep incline towards the Panamint Valley.

We actually had fog in this arid environment, since the clouds were crowding against the edge of the steep mountains. As we passed the Father Crowley Vista Point, the clouds briefly parted and we had a view into the deep gorge of Rainbow Canyon. At this point, the slopes and flats are covered with basaltic lava flows ranging in age from 8 to 4 million years old. The immediate question becomes, why volcanoes? Why right here?

In a sense, volcanism is possible almost anywhere on the planet. It's not that there is magma everywhere, but that a hundred miles beneath our feet there is a zone, the asthenosphere, where the rock is almost molten, but not quite (perhaps 5-10% liquid). To melt this rock and create volcanic activity would require raising the temperature (as happens at hot spots like Hawai'i), or releasing pressure (pressure keeps the rocks from melting in the same way that pressure cookers prevent water from boiling). There aren't any hot spots in the immediate vicinity, but the crust across the Basin and Range Province has been stretched and thinned, allowing pockets of basaltic magma to form and rise into the rocks above, often following fault zones to the surface.

Although we couldn't see it through the clouds, there are basaltic lavas across the Panamint Valley that are of the same age and the same exact composition as those at the vista point. In addition, the rocks across the deep valley have no obvious source (the picture below is from last year, a decidedly drier trip). The best explanation for these rocks is that the lavas flowed across an original surface that was later broken up by faulting when the Panamint Valley formed. Since the youngest volcanic rocks are just 4 million years old, the Panamint Valley is younger still. The Panamint Valley is more than a mile deep and 65 miles long! That's a lot of geologic activity in a short period of time.

Looking across the Panamint Valley towards Hunter Mountain. The dark rocks on the left summit area are identical to the rocks at Father Crowley Vista Point.

We made a stop along the road descending into the Panamint Valley to check out some spectacular exposures of the dikes and sills that once fed the eruptions of the basaltic lavas (most years we are in too much of a hurry to get a camping spot at Stovepipe Wells). The magma was following whatever weakness in the surrounding rock that could be exploited by the molten rock. In some cases, vertical fractures allowed the magma to rise, forming dikes. In other cases, the molten rock flowed between limestone layers, forming sills. This extraordinary roadcut (below) showed textbook examples of both kinds of intrusions in the same outcrop. The usually black basalt has been oxidized (rusted) to produce the strange reddish-brown color.

There's a saying that one should never blindly sit on the ground in the desert. There are just too many things with fangs, stingers, or spines. The barrel cacti were looking to grow quickly in these rare wet times!

We headed down the highway. We had reached Death Valley National Park, and we faced whatever Bombogenesis was going to throw at us...

So, Besides Fish, What's the Last Thing One Would Ever Expect to See in Death Valley National Park?

It's one thing to find that a number of fish species survive within the boundaries of Death Valley National Park, which preserves the hottest and driest desert in North America. But sure, springs will persist in many dry environments. But a permanent, year-round waterfall? Yes, there is one in Death Valley National Park.

When Death Valley was changed from a national monument to a national park in 1994, the boundaries were vastly expanded, and came to include a portion of the Darwin Plateau at the south end of the Inyo Mountains southeast of Owens Lake. Part of the reason this area was included was the presence of a permanent stream, and its importance as a wildlife area. And there was Darwin Falls as well.

The falls are a short walk up a canyon just upstream of the Panamint Springs Resort on Highway 190. Indeed the water at Darwin Falls isn't just for the wildlife. A pipeline runs the length of the canyon providing the precious liquid to the resort as well.

There is some excellent geology exposed in the canyon walls on the way to the falls. One example is this excellent exposure of a dike, an intrusion that cuts across the sedimentary layers. There are nice examples of jointing in the granitic rocks exposed a little farther upstream.

Then comes the unexpected thickets of vegetation and the sound of trickling water. The trees are so thick it is a little tricky getting a clear shot of the lower falls. The falls are about 20 feet high, pretty small by any standards, but we are talking about a desert environment here. I understand several other falls are present upstream for a total drop of 80 feet or so.

These pictures are from 2008. I've only made it to the falls the one time, but I'd like to get up there again, maybe when the sun hasn't practically set! Thanks to commenter "twoeightnine" for jogging my memory about this extraordinary place in Death Valley!

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Another Cool California Roadcut: Dike and Sill on Highway 190 near Panamint Springs

Dike (vertical brown rock) and sill (horizontal brown rock) along Highway 190 near Panamint Springs

I've been working through my memories of beautifully instructive roadcuts in California. Some, like the Big Pumice Cut and the Charlie Brown Outcrop, are quite famous to geologists and generations of field studies students. Others have received less attention, and today I'm showing a particularly nice spot to learn about the difference between a dike and a sill.

A dike is an intrusion of molten rock that is tabular (thin, but deep and wide, as it fills fractures in the rock), and discordant (it cuts across rock layers). A sill is also tabular, but it is concordant, meaning it squeezes between layers rather than cutting across like a dike.

Highway 190 provides access to Death Valley National Park from the west at Lone Pine and Olancha. It travels around the south edge of Owens Lake, and then crosses the Darwin Plateau before beginning a steep descent into the Panamint Valley. From there it crosses the Panamint Mountains at Townes Pass and enters into Death Valley.

The Darwin Plateau is capped with multiple layers of basaltic rock covering a sequence of Paleozoic limestone layers. Midway down the stretch between the turnoff to Darwin and the resort of Panamint Springs there is a spectacular exposure of a dike and a sill in the same roadcut. The basaltic intrusion has been weathered to an orange-brown color. The Paleozoic-aged limestone is gray and has clearly delineated layering that makes it a straightforward exercise to distinguish the two types of intrusions that cut through it.

I wish I could say that this is a favorite stop on our way to Death Valley, but unfortunately we are usually running late by the time we reach it late in the afternoon on our way to Stovepipe Wells. It is a marvelous example of both kinds of intrusions.

Where are the Ten Most Incredible Places You've Ever Stood? My Number 2: The Grandest Canyon of All

A clearing storm in Carbon Canyon, a tributary to the Grand Canyon

Of course, the Grand Canyon was going to appear on a list like this. It is one of the great spectacles of geology on planet Earth, and it has been entwined with my life many times over. I can trace the first inklings of my curiosity about geology to a vacation at the North Rim when I was a child of nine or ten. Picking up fossils in a meadow along the highway north of the park, I wondered how they could have ended up at 8,000 feet above sea level. A decade later I was a gawky thin teenager in his first year of college looking for direction in his life. A week below the rim on the New Hance and Grandview trails with an inspirational professor provided the impetus for following a career in geology. And then there has been the nearly three decades of leading students to this stunning place, introducing them to this most incredible gorge and the geological history it reveals. Yes, the Grand Canyon is one of the ten most incredible places I've ever stood.

The Desert View Watchtower on the eastern edge of the South Rim of Grand Canyon.

But there is a problem with picking the Grand Canyon as one of my "spots". It's a really big place! There are 200-plus river miles, the canyon is a mile deep and ten or fifteen miles wide, and has countless side canyons and tributaries (so many that a lot are named after their mileage along the river, i.e. Two-hundred Mile Canyon). Many of the side canyons would be national parks of their own in any other setting; Havasu Canyon and National Canyon are tens of miles long, and just as deep as the main gorge.

Mather Point, possibly. I didn't label this one!

So do you pick the rim? This is where most people see the canyon for the first time. There are two rims of course, the North and the South. Probably 90% of the park's visitors come to the South Rim, and that is where most of the facilities are located. It has some grand viewpoints, including, um, Grandview Point. I love visiting there, but it isn't the most incredible part I've stood on.

The North Rim is distinctly different. A thousand feet higher than the South Rim, it is covered with an extensive cool forest of fir and ponderosa. It's lonelier, with a single resort, a small camper store and a campground (check out the excellent Geogypsy Traveler blog for the perspectives of a North Rim ranger). No matter where I am on the North Rim, it feels more wild. It's one of my most cherished places in the world. But I can't pick out a single spot that I've stood on that set it apart from other areas of the canyon.

There are the archaeological sites. People have lived on and in the Grand Canyon for more than 4,000 years, and have left behind intriguing clues about their lives and beliefs, including the split-twig figurines and multitudes of petroglyphs and pictographs. Had I not ended up a geologist, I would most certainly have followed archaeology as a career. The Grand Canyon has some great archaeology, but I couldn't pick a single spot that represents all the canyon means to me.

It took a lot of consideration, but in the end, I knew the "spot" would have to be Hance Rapids at Mile 77 on the Colorado River. So many things in my life converged at this spot. The New Hance Trail reaches the river at this point. I walked the trail in 1976 on my first geology field studies trip and stood on the shore of the Colorado River for the first time. I had walked through 1.7 billion years of earth history to reach this spot, seeing the rocks I had been studying in class for the previous two months. The history of the canyon came alive to me as I walked in wonderment, seeing the crossbedding in sandstone caused by wind blowing over dunes 300 million years ago, the footprints of pre-dinosaurian reptiles and amphibians, the ripplemarks of long-gone rivers and beaches, and fossils from times before multicelled life existed on the planet.

It is at this point that river-runners first encounter the Granite Gorge, the Inner Canyon of the Grand Canyon. The rocks are schist and gneiss 1.7 billion years old  that formed in the roots of a long-gone mountain range that until recently was hidden in the deep crust of the lithosphere. Only in the last five or six million years has the Colorado River exposed these rocks to view. It was near this spot that John Wesley Powell wrote his immortal words about the Grand Canyon: "We are now ready to start on our way down the Great Unknown...We are three quarters of a mile in the depths of the earth...We have an unknown distance yet to run, an unknown river yet to explore. What falls there are, we know not; what rocks beset the channel, we know not; what walls rise over the river, we know not."

The Great Unconformity separates these ancient rocks from the only somewhat younger rocks of the Grand Canyon Supergroup (the reddish sediments on the right in the picture below).  The Supergroup is a group of late Proterozoic sediments that are three times as thick as the main sequence of Paleozoic rocks that make the upper 4,000 feet of the Grand Canyon cliffs. They were faulted, tilted, eroded, and ultimately buried by the advancing Cambrian sea of 515 million years ago. It may be the most famous unconformity on the planet.

This was the spot where I became a geologist.

I returned to Hance Rapids last summer for the first time in thirty years, only this time I came by raft rather than by foot. I am still processing that journey in my mind, but I already know that it was one of the most significant events in my life. I became aware of the fragile nature of life, first among the plants and animals in this challenging environment, but also of my own. Aside from the profound risk of driving a car every day, I came the closest I've ever been to realizing the possibility of death when I was dumped into the near freezing water and rode the toughest rapid for more than a quarter of a mile. We went over more than 150 rapids in seventeen days, and Hance was the first of the monster rapids, rated 8 or 9 on a scale of 10.

Some pictures surfaced a couple of years ago on my Facebook page of that first profound adventure that I had in 1976. It's remarkable how little the river and the rocks have changed, but I realized how much has changed in our understanding of how the rocks of the canyon accumulated, and how the canyon itself came into being. Plate tectonics had been accepted only a few years prior to my arrival in the canyon, and the tectonic history was only just then getting worked out. Parts of the story are still mysterious.

I also realize the massive changes in my own life since then. Back then, there was a dedicated geology professor discussing the history of the canyon, and a young man making life-changing decisions in the professor's class. The young man had not yet married, there were no children in his life, he had not earned a living on his own. He was just starting out.

Today, my kids are grown, I get awards for longevity at my job, and I'm closer to the end of my career than I am to its beginning. I am a teacher now, but I continue to be a student as well, seeking out new places, and revisiting the old ones from the past for continuing enlightenment. The canyon will continue to exist, changed only in a few ways during my tenure on the planet. It knows or cares little of the latest life form that scrabbles about its surface, and it will shrug off the gigantic reservoirs we've constructed to try and control the river.

The canyon is an incredible place. It gives us perspective in so many ways, and that's why it ended up as number two on the list of the most incredible places I've ever stood.

Just who is that thin person in the yellow jacket??

Where are the Ten Most Incredible Places You've Ever Stood? My Number 5: Walking in the Footsteps of James Hutton

This entry into my series on the "Ten Most Incredible Places I've Ever Stood" is sort of a two-for-one deal. It was my journey into a different kind of geological past, the history of the science rather than the history of the world, although that was part of the story too. This was a visit to the birthplace of geology as a science, at two locations in Scotland.

"What clearer evidence could we have had of the different formation of these rocks, and of the long interval which separated their formation, had we actually seen them emerging from the bosom the deep? We felt ourselves necessarily carried back to the time when the schistus on which we stood was yet at the bottom of the sea, and when the sandstone before us was only beginning to be deposited in the shape of sand or mud, from the waters of a superincumbent ocean. An epocha still more remote presented itself, when even the most ancient of these rocks instead of standing upright in vertical beds, lay in horizontal planes at the bottom of the sea, and was not yet disturbed by that immeasurable force which has burst asunder the solid pavement of the globe. Revolutions still more remote appeared in the distance of this extraordinary perspective. The mind seemed to grow giddy by looking so far into the abyss of time...."

These are the words written by John Playfair as he described an extraordinary boat journey he made with James Hutton in 1788 to Siccar Point, a spot where Hutton found confirmation of his model of the Earth's development. At the point, Silurian graywacke sandstone layers (425 million years old) stand nearly vertical, and are overlain by bright orange and brown layers of the Devonian Old Red Sandstone (345 million years). Such features are called unconformities. During the interval of time before the deposition of the Old Red Sandstone, the sea floor had been compressed and thrust upwards into a mountain range that was subsequently eroded completely away. Such events required the passage of vast amounts of time, something quite incompatible with the mere 6,000 years of Earth's existence assumed by medieval religious scholars. Hutton's explorations of Scotland ignited the revolution that led to the development of the science of geology.

In 2001 I had the chance to visit some of Hutton's most famous rock exposures. We had put together our very first international field studies journey to England and Scotland, and being unfamiliar with the territory, we had contracted with a tour company to take care of the logistics. We got a canned tour of the famous tourist localities like Stonehenge, Big Ben, and Edinburgh Castle, but we made special arrangements with the tour company (for a price) to deviate from their usual itinerary (we missed the golf courses of St. Andrews) so we could instead head into the southern uplands of Scotland to Siccar Point. We committed to the trip 1 1/2 years in advance, having no idea that hoof-and-mouth disease was about to be detected in the British Isles, including the farms around Siccar Point. To my almost unspeakable frustration, access was impossible. Not wanting to just give up, I pulled out the topo maps and we made our way to a campground on the coast about a mile north of Siccar Point. I read the passage from John Playfair to the students, and than I ran as far as I could along the beach cliffs to where I could see the point, but not the relationships (although we could pick up the associated rocks along the coast).

The idea of unconformities and the concept of geological time would have been enough to secure Hutton's reputation as a geological pioneer, but he made another profound observation in the middle of the city of Edinburgh. That was the second spot I was seeking on this geological pilgrimage.

For years I've been showing a video to my students on the development of the theory of plate tectonics. It was done in the early 1990s but has held up well aside from the ancient computers in some of the scenes. It begins in Edinburgh with a look at the Salisbury Crags and Arthur's Seat, where James Hutton discovered an ancient volcano that once sat on the sea floor. Other observers in these early days of geology thought that basalt accumulated on the sea floor by precipitating out of the water, much like salt deposits in a drying bay. Hutton found a contact zone in a small quarry at the base of the Salisbury Crags where the intruding basaltic rock had pried up the previously existing sedimentary layers forming a vast sill. In other parts of Scotland he found intrusions of granitic rock that had done the same thing. In short, he had discovered intrusive (or plutonic) igneous rocks, and opened our eyes to an entirely different way of considering our planet, an active planet with an internal heat source, and cyclical processes that had been operating for millions, not thousands, of years.

I didn't have much of a clue about how to find the quarry, but sunset came late in our northern latitude, so after dinner I set out from our hotel and walked to the crags. It didn't actually take very long before I found a concrete monument and the very exposure that had been illustrated in Hutton's early books. It was a marvelous moment in my geological life (and a great sense of relief because I was going to be showing it to my students the next morning and had to pretend I knew where it was all along).

The big adventure of the next day would be the climb up to the summit of Arthur's Seat, the eroded and glacially scoured volcano that had once been in an ocean. The peak is surrounded by the city of Edinburgh, and was originally preserved as a deer hunting park for the king, but more recently because of a number of rare plant and animal species, as well as being a bit of greenery in an urban setting.

The peak is an archaeological treasure with the remains of ancient fort at the summit, and the ruins of a chapel, St. Anthony's, built in 1425 on the flanks. It was such a strange sight for the middle of a city.

Although it was a bit hazy, the whole city was visible from our 822 foot summit. We could sit on our "throne" and consider the volcanic eruptions that built up the volcano, the continental collision that deformed and tilted the rocks, and the glaciers that scoured the flanks during the ice ages of the last two million years.

Do these pictures look a little fuzzy, a bit low of resolution? There's a story there. I had heard of digital cameras, but they were expensive and I couldn't fit them in my budget (my, how times have changed...). Because the Scotland trip was a major event for our department, I convinced the administration to spring for a modest camera (an entire 3 megapixels!), and it arrived in Shipping and Receiving late in the afternoon before our departure the next morning. When I got on the plane, I had taken and downloaded all of three images. I barely knew how to use the camera, and didn't really trust the technology, so I ended up mostly taking lower resolution pictures. I would never make that mistake again, but such is the learning curve. At least I didn't accidentally delete them all like I've done on a few other occasions. If you would like to see some very excellent and more recent pictures of Arthur's Seat, check out this recent post at Magma Cum Laude: http://blogs.agu.org/magmacumlaude/2014/04/06/edinburgh-arthurs-seat-and-salisbury-crags/

Not many people in Edinburgh know of James Hutton, and his role in the development of the science of geology. Mostly I got blank stares when I asked directions to the monument. James Hutton is buried in Edinburgh and we paid a visit to the cemetery, but they had to pull out a catalog to find out where he lies buried. The section of the cemetery where he is interred was locked and chained, apparently because of continuing abuse by leaders of the popular ghost walks of Edinburgh (yeah, I took one too, but aside from atmospheric fog in the streets I was unimpressed).

Hutton's resting place is on the left side of this yard.

How much does the average person know about Scotland and England? That there is a queen, and the men wear kilts. We of course realized that we weren't going to be seeing any queens, and it was silly to think that all the men in Edinburgh would be going around in kilts. Except that both of those things happened!

As we made our way down the road towards Arthur's Seat, we noticed that nearly every man on the street was wearing a formal kilt, and we wondered why. As we approached Holyrood Palace, we realized that everyone was gathering for a "garden party" hosted by Queen Elizabeth. There were just a few people in attendance, about 8,000 of them. From our vantage point on the flank of Arthur's Seat, we could pick her out, wearing a blue outfit in a receiving line next to the side of the building just slightly left of center in the picture below. Yes, it was a crazy, unique day.

Just to accent the weirdness, we passed the street sign below. It wasn't actually a prophecy, but instead was an alleyway (a 'close') on the edge of the old city, which was the edge of the world to the medieval inhabitants.