Rock and Light: The Primal Elements of Death Valley, Monochrome Edition

Sorry for going all pseudo-Ansel Adams on you all. I was playing with the photo-editing program with the pictures that I used in yesterday's post, and at one point I switched to black and white. I'm enchanted by the colors of our planet, but it is easy to forget that features can often be better discerned in monochrome photos.

It's almost as if the blinding sun, so unexpected, blinded me to the textures and depth of the rocks revealed in the slopes of the northern Black Mountains of Death Valley National Park.  Monochrome imagery is something that really has only existed since the advent of photography, and its value today is in the unexpectedness of the image. We expect color, but it's not there. As Wikipedia (the ultimate authority) would put it, monochromatic images "are not direct renditions of their subjects, but are abstractions from reality". And yet, science illustrators often prefer to show objects of research in black and white, or even as drawings to emphasize the ultimate reality of their findings.

It occurs to me that monochrome images do have an impact on the human psyche, and it exists at a very fundamental level. Our vision at night is monochrome, and humans evolved with a certain primal fear of the darkness. One can't see approaching predators in the dark, and in low light one would be highly attuned to noticing small changes or movement in one's field of vision. Black and white images capture our attention in a way that color images just can't.

In any case, I was mainly looking for an excuse to put up some pictures that I found interesting. Badlands topography has always been a good subject for black and white photography because of the strong contrasts between light and shadow, and the Furnace Creek Formation is the ultimate expression of badlands.

Rock and Light, the Primal Elements of Death Valley

When one has been under gloomy overcast conditions punctuated by periods of rain for days, the novelty can run short, even in a place where rain is scarce. We had been on the road for three days and in that time we saw no sunshine, and in fact had lived through a night of record rainfall and localized flooding. What made the mood worse was that the weather forecasts had us expecting sunshine on the third day and we got rain instead.

The students were just great actually, showing all kinds of patience. They were in Death Valley after all, and they weren't in a classroom. At least not the kind with four walls. Just the same, I was pining for just a bit of sunlight, and the evening was coming quickly. We had just finished an exercise at Gower Gulch at the north end of the Black Mountains and we walking back to the vehicles when a sliver of sky opened up. The sun blazed forth in all its glory.

There are two sure things in places like Death Valley, rock and light. Deserts have dust storms at times, of course, but much of the time the air is free of pollution and humidity. The sun shines with an intensity not usually experienced in urban settings (my students traditionally come home with winter sunburns despite our warnings to use sunscreen).

And the rock...Death Valley has perhaps the greatest variety of rock types to be found in any national park. They range in age from 1.7 billion to practically yesterday. They include all of the types, plutonic, volcanic, sedimentary, and metamorphic. The rocks occur in nearly all the colors of the rainbow, sometimes in a single outcrop (google Death Valley's Artist Palette if you want to see what I mean). And in most parts of the park there is no vegetation or soil to obscure their complicated structures and relationships.

It's hard to imagine a more dramatic moment for the two elements to intersect. The sun was low in the sky, the rocks were wet from the recent rain storm, so the colors were intensified and the rocks seemed to glow with an inner light.

The rocks we were looking at were part of the Mio-Pliocene sediments and ash/lava flows of the Furnace Creek, Funeral, and Artist Drive formations. They accumulated in a fault basin not totally unlike the present-day Death Valley graben. There were ephemeral lakes, alluvial fans, floodplains, and volcanoes. The plains probably supported a rich fauna of camels, horses, mastodons, birds and predatory cats, who left their tracks in similar-aged rocks elsewhere in the park.

It was a dramatic moment, but as with so many such moments, it was fleeting. The clouds closed in again, and we thought the show was over, except that a few moments later while we drove the highway north of Furnace Creek, the skies opened up one more time to reveal a brilliant rainbow (see the opening picture...as if you somehow missed it!). The moment felt perfect.

Addendum: Since we are talking the incredible fossil record of Death Valley, there is news this week of some horrible human beings who have stolen some of the precious fossil trackways I mentioned. I can only hope that the pictures of the probable thieves will lead to arrests and convictions. More information can be found here: http://vertpaleo.org/Society-News/SVP-Paleo-News/Paleontology-News/Fossils-Stolen-from-Death-Valley-National-Park.aspx

Travels in Death Valley: the Strange Story Told By a "Rock"...

A beautiful collection of colorful rocks lie scattered across the surface of an alluvial fan in Death Valley National Park a few miles south of Furnace Creek. There is a piece of vesicular (full of holes) basalt on the lower right, next to a piece of gray limestone. One might be just 10 million years old, while the other may be 300 million, containing the remains of long dead and extinct organisms. At the top left, a piece of orange-brown sandstone, possibly deposited on an ancient ocean shoreline, or maybe a lakeshore in a long-ago desert, maybe even a sand dune. Perhaps a piece of granite is in there somewhere, a rock that cooled four or five miles deep in the crust. What a long journey it had before it was exposed by erosion and carried down the desert wash! And then there is...wait...what is that at center left? That's no conglomerate! Well it sort of is, but isn't natural is it? That's a piece of pavement. What's going on here?

It's not a story that appears on National Park Service interpretive signs, and in fact I think the park service would rather that people not explore the particular canyon at all. It's sort of unstable, as in vertical walls made of loose and cracked chunks of claystone. And like the piece of asphalt pavement on the alluvial fan surface, it's not natural either. This canyon didn't exist 75 years ago.

Gower Gulch used to be a minor drainage in the Furnace Creek Formation badlands near Zabriskie Point which debouched onto the floor of Death Valley, forming a small alluvial fan. Badwater Road crossed the fan, which consisted of mostly fine-grained materials like silt and clay.

The problem is that nearby Furnace Creek drained a much larger region than Gower Gulch (170 square miles versus 2 square miles), and was prone to violent flashfloods and mudflows that damaged facilities at the Furnace Creek Resort about five miles downstream. Around 1941 someone thought to blast through the low ridge that separated Furnace Creek and Gower Gulch, forcing the entire drainage to flow through the badlands and onto the Gower Gulch fan downstream. The diversion caused profound changes upstream and downstream.

At the diversion point (above), the flash floods cut through the soft siltstone and shale like a hot knife through butter, cutting 40 feet or more in seven decades. The floods carry a heavy load of coarse-grained debris and gravel that acts as an abrasive on the channel floor. The canyon changes year to year as each flashflood causes slopes to be undercut, causing rockfalls and slope failures.

It's upstream where serious damage to the road occurs. The diversion caused a sudden steepening of the Furnace Creek channel, and the faster moving floods have eroded the channel in an upstream direction, a process called headward erosion. The deepening of the channel is apparent as far as two miles upstream, and in numerous places it has encroached onto Highway 190, washing away some of the pavement, and incorporating the fragments into the alluvial fan deposits downstream (as in the first picture above).

Downstream, the road damage occurs in a different way. The alluvial fan used to receive fine-grained silt and clay in relatively minor floods that did little damage to Badwater Road. Now the flashfloods are on steroids, so to speak, with more water, more debris, and far more speed. Badwater Road is regularly overwhelmed, as it was on the day we visited, with mudflow deposits. Boulders can sometimes be sizable. For example, check out the two fragments on the fan in the picture below. How big do you think they are?

Here's your answer: pretty big.

Death Valley is a monument to geologic changes over billions of years, but it is also a dynamic environment where geologic change happens on a daily and yearly basis as well. We saw plenty of evidence during our February trip.

Death Valley is Really Second Generation Death Valley: A Look at Death Valley Version 1.0

Death Valley is a stunning example of a fault graben, a large area of crust that subsided because of extensional forces that produced widespread "normal" faulting (where the fault plane slopes towards the basin). The valley has relief of more than two miles, from the summit of Telescope Peak at 11,043 feet (6,168 meters) to Badwater Basin at minus 282 feet (-86 meters). Perhaps more extraordinary is the fact that the valley has filled with eroded sediments to a depth of as much as 9,000 feet. Remove the sediment and Death Valley would be nearly four miles deep!

One might imagine what it would look like if the sediments of Death Valley were somehow lifted up and dissected by erosion. What would one see? There would no doubt be layers of salt and gypsum, silt and clay, and conglomerate and breccia from the alluvial fans that line the margins of the valley. Volcanoes are found along the margins of the Death Valley today. Perhaps one could expect to see colorful exposures of lava and tuff in the deeply buried valley sediments.

What's fascinating about Death Valley is that we don't have to imagine what the valley fill would look like. It turns out that the graben that formed the valley is not the first to have existed in this area. It formed around two or three million years ago, but extensional forces have been stretching this region for something like 15-16 million years. Other grabens developed, filled with thousands of feet of sediment, and were lifted by faulting so that erosion revealed the underlying rock and sediment. One of these more ancient basins is revealed at Zabriskie Point, one of the most visited and dramatic of Death Valley's tourist destinations. The rock is called the Furnace Creek formation.

The rocks of Death Valley-Version 1.0, as seen in the Furnace Creek formation consist of fine-grained silt and clay interspersed with evaporate minerals like salt, gypsum, and most importantly for the miners of Death Valley, borates. There are layers of conglomerate and breccia from ancient alluvial fans, and colorful tuff and lava flows from associated volcanic activity. In the dry environment of Death Valley, the rocks have eroded into the intricate badlands that made Zabriskie Point a must-see part of any trip to the park.

The badlands are practically devoid of any kind of plant life. The barrenness results from the inability of stable soils to develop on the steep slopes. Any soils are quickly washed away during infrequent but violent cloudbursts.

The layers exposed in the Furnace Creek formation provide information about ancient environments that once existed in the Death Valley region, but also feed the imagination about the rocks hidden deep within today's fault graben, Death Valley-Version 2.0.

This has been another in an off and on series about our February visit to Death Valley. In the next installment, we'll be leaving Death Valley for other sights in the region, a detour made necessary by October flash floods that took out some of the park's roads. We'll be visiting a unique biological island in the desert...

A Sight That Overwhelms: Dante's View and a Sense of Scale

It's one of the most astonishing viewpoints in all of North America. The Black Mountains form the eastern edge of Death Valley, and they are one of the most rugged mountain fronts in existence. In places the mountains are so steep that one cannot see the slopes at the base from the summit. Looking up from the lowest point in North America, Badwater, one can barely contemplate walking or driving to the summit across the barren cliffs.

And yet a road does just that. Taking advantage of the asymmetrical nature of the range, a paved road winds up the eastern flanks, and only the last few hundred yards of the drive are a vertiginous nightmare. And then there is a view like no other.

Death Valley is the largest national park in the lower forty-eight states, and Dante's View takes in much of the park, offering on clear days a view that extends across more than a hundred miles of desert ranges and salt flats. The view is so unlike any other place on the planet that George Lucas used it as setting for his alien planet in some movie about wars across the stars ("Mos Eisley spaceport. You will never find a more wretched hive of scum and villainy.").

Even though the summits reach nearly 6,000 feet above sea level, the slopes are barren and dry. The range lies in the rain shadow of the Sierra Nevada and two other high mountain ranges, including the Panamints that rise to 11,000 feet on the other side of Death Valley. In any other mountain range, 6,000 feet would support a thick forest. Here in the Black Mountains, only sage and seasonal wildflowers can grow.

The lack of vegetation is a boon to the geologist, of course. The exposures of bedrock are unparalleled, revealing a great deal about the geologic history of this part of the world. And it is a strange story. Much of the mountain range is composed of the Black Mountain Metamorphic Complex, a selection of gneiss and schist sequences that reveal evidence of a titanic series of plate collisions 1.7 billion years ago. At that time, North America was hit by a series of terranes, island systems maybe the size of New Zealand or California. The collisons produced a mountain range hundreds of miles long that would recall the coastal ranges of southern Alaska, minus the rainforests (terrestrial life didn't arise for at least another 1.2 billion years). These rocks are related to those found in the depths of the Grand Canyon and farther south in Arizona and New Mexico.

In the ensuing years, the vast range would be eroded to a nearly flat plain, and the surface would eventually subside below sea level. Tens of thousands of feet of Paleozoic sediments covered the rocks so they lay hidden deep in the continental crust. In the last few tens of millions of years, the regional crust was stretched and extended, and the overlying rocks slid away, causing the Black Mountains to "pop up" in the geologically short stretch of two or three million years. The exposure of the deep crust was accompanied by violent caldera eruptions, and parts of the mountain range are covered by colorful ash deposits (the rocks along Artists Drive Loop are particularly memorable).

Some places are so overwhelming that one can lose a sense of scale while staring into the abyss. Take a look at the picture below: we are looking at the vast salt pan of the Badwater Basin, the lowest place in North America at minus 282 feet. The salt flats cover 110 square miles. How big an area is this?

To find out, take a look at the thin channel of salt marked with the arrow in the picture above. We'll zoom in a bit, and find that we are looking at a spot next to the Badwater parking lot, which is just out of sight at the bottom of the picture. One can make out the Badwater Road on the left side of the photo. What are those dots on the salt channel? Let's zoom in a bit more (120x by now).

They're tourists! Badwater is a main destination for visitors to Death Valley. The stop lies 5,700 feet beneath Dante's View, and only two miles west. These mountains are about as steep as any can be.

The view from Dante's View on this afternoon in February was unique for me. Flash floods in October had destroyed some roads in the park, and I found it necessary to alter our usual itinerary. We usually see the viewpoint in the early morning. Until this day I had never seen the sun set over desert like this. It was an astounding sight. Even overwhelming...

Scenes from a Superbloom: Death Valley 2016 (Part 1 of 2)

I could have made up a detailed geological description of the geology of this alluvial plain at the south end of the Death Valley graben. This is a geology blog, after all. But we were there in the middle of February during the most extraordinary flower show, a "superbloom", in a decade. A series of fall storms were spaced just well enough to wake up the myriads of seeds that hide in the soil, biding their time and waiting for the right conditions to bloom. And this was the time. I'm showing flowers today!

First and foremost is the Desert Five Spot (Eremalche rotundifolia). I'm in Death Valley every year during February, and I might see a few flowers scattered about even in dry years, but I only find the Five Spots during years like this, and I have almost no good pictures of them. That changed this year!

The slopes were covered with Desert Gold (Geraea canescens). A few Desert Golds seem to sprout in the dry years, but if there is water, these are the flowers that turn the slopes and fans bright yellow. It almost feels like walking through alpine meadows, yet one can never escape the sense that these flowers are growing as fast as they can, setting seeds, and dying as the hot winds begin to blow (and the hot winds can come at any time of the year).

Another dependable flower even in drier years is the Desert Sand Verbena (Abronia villosa). There were lots of them in the washes at Ashford this year.

The Ashford Mill was built to process gold ores from a mine a few miles away in the Black Mountains. A bit of gold was produced over the years, but the total output was described as providing the owners with little more than "groceries and lawsuits". Not much is left beyond a few walls and foundations, but they provide a decent frame for viewing Telescope Peak.

The Black Mountains form the eastern wall of the south part of Death Valley, and they are one of the most rugged mountain ranges to be found anywhere. The steepness results from the rapid uplift of the mountains (or rapid subsidence of the valley floor, or both), and the slow rate of erosion in the exceedingly dry climate of eastern California. In this season of "plenty" (in the relative sense, of course), they provide a somber backdrop to the rich display of flowers across the valley floor.

In the next post, we'll check out a few other flowers from another spot just up the highway.

Like a Gigantic Babushka Doll, One Death Valley inside Another Death Valley

Death Valley is a deep structural trough called a graben, formed by faults that stretched and broke the continental crust, mostly within the last two or three million years. It is just one of dozens that are present across the deserts of eastern California, all of Nevada, and much of western Utah, a region known as the Basin and Range Province.  But as grabens go, Death Valley stands out. It is almost twice as deep as the Grand Canyon, as the Panamint Mountains slope 11,000 feet down to the valley floor that sits below sea level. It's also one of the flattest places you can stand on planet Earth.

But the valley we see is only part of the story. As is always true of any mountain, if it sticks up into the atmosphere, it will be eroded. It doesn't matter how dry the climate is, erosion happens anyway, albeit at a slower pace perhaps. Sediments have been filling in these valleys. As high as the mountains are, another two miles are hidden by the sediments that fill the valley floor.

I imagine some people wonder what's under all that salt. Wouldn't it be cool to see some of the history revealed in those sediments?

All I can say is that Death Valley is one awesome piece of geology. Whatever you might seek about geological processes or history, there is probably a world-class example of it at the park. So you want to see what Death Valley would look like from the inside-out? We've got you covered! There have actually been two Death Valleys, and one of them has been turned on end for us to explore.

About 5 or 6 million years ago, extensional forces were stretching the crust in the Death Valley region, but from a different direction. A major fault graben opened up in a northwest/southeast direction, mountains rose on either side, and erosion began to fill in the trough. Eventually the sediments accumulated to a depth of a mile. Sometimes a permanent lake filled much of the valley, resulting in the deposition of layers of fine silt and clay. At other times, the lake dried up, leaving behind halite (table salt), gypsum, and borate minerals. Alluvial fans, composed of gravel and conglomerate, sometimes spread across the valley floor. There were occasional volcanic eruptions as well.

The sequence of sediments and lava flows is called the Furnace Creek formation. Few fossils are found in the rock, but trackways of horses, camels, mastodons, large cat and wolf ancestors, and birds have been found. These fossils point to a diverse ecosystem that was not quite as dry as that of today's Death Valley, but is certainly analogous to the Death Valley that existed during the ice ages.

Then things changed.

The regional stress pattern shifted and new faults formed, the faults that produced the present-day Death Valley graben. The deeply buried rocks of the Furnace Creek formation were pushed upwards, folded and tilted, and ultimately exposed to erosion. In the harsh desert climate soils do not develop on the fine silts, so the barren slopes give way to deep gullies and furrows called badlands topography.

And so today, we can have a look at Death Valley from the inside out.

Most tourists who visit Death Valley observe the Furnace Creek formation at the spectacular view from Zabriskie Point or from the resort area at Furnace Creek. We usually do a field exercise at Zabriskie, but the entire area was closed this year for renovation. So we headed up Twenty-Mule Team Canyon for a look at the colorful outcrops. The gravel road winds for several beautiful miles through the badlands.

The Furnace Creek formation was the greatest source of riches in the Death Valley region. Forget gold or silver or copper. The borate minerals, formed from geothermal hot springs in the graben of the Furnace Creek formation, were mined for their use as soaps and detergents, a flux in glass-making, in cosmetics, and numerous other applications. For a number of years in the late 1800s the only economic sources of the borate minerals in the world were in Turkey and Death Valley. They were still being mined in Death Valley as recently as 2005.

The Furnace Creek formation is a spectacular part of the scenery of Death Valley National Park, but the colorful exposures provide a window into the geologic history of the western United States as well. Peel away the surface layers and we find pieces of the past when conditions were far different. Peel back that layer, and we find another story.The Furnace Creek formation is but one of dozens of geologic strata exposing more than a billion years of changing environmental conditions. The park is one giant Babushka doll of geologic history.

A Sere and Barren Place. And the Biggest National Park in America's Lower Forty-Eight.

People don't feel isolation very often. Well, plenty of us do feel isolated, but it tends to be an isolation in which we are surrounded by people and the trappings of civilization, but are separated by our life situations, our depression, and our dependence on technology instead of our social skills. But how often are we completely cut off from civilization? I imagine it's somewhat rare these days.

In many parts of the country it is just plain impossible. Humans have made their mark on the land, paving it over, building cities, plowing farms. If the land is useful to humans in any way, it gets used up, and then some. And barren lands make many people uncomfortable to say the least. We seek the cities and towns for the most part.

It's a learning experience to see, and feel, the wild places. The Earth is the source of our water, our food, our material resources, and sometimes our inspiration. It's easy to take it for granted if we don't understand how it works. Which, in a nutshell, is why I teach, and why I take people to the wild places. And there are few places as wild and isolated as Death Valley National Park, the largest national park outside of Alaska.

It's true that about a million people visit the park every year, but they spend almost all their time at three places: Furnace Creek, Stovepipe Wells, and Scotty's Castle. They venture forth to Dante's View and Badwater, but invariably head back to the small outposts of civilization where they sleep in hotel rooms, RVs, or tents, and eat in the few restaurants. But there are those moments that people do experience a sense of the wild.

Badwater is one of those places where it is at least momentarily possible. People go there in droves because it is the lowest point in the western hemisphere (-280 feet; 86 meters), but they often step away from the parking lot and the interpretive signs and start walking onto the Death Valley salt pan, 110 square miles of barren salt and clay. It doesn't take but a few moments before the cars shrink to insignificance, and there is only the silence, or maybe just a bit of wind. Nothing lives there. One is standing in the bottom of a valley more than one hundred miles long with only a thin artery of pavement, and two little outposts of civilization thirty miles apart. It's about as close to the primeval Earth as one can be.

You are standing in one of the world's greatest geologic landscapes. The mountains to the east contain metamorphic rocks 1.7 billion years old, recording in their convoluted folds the collision of huge landmasses and growth of a gigantic mountain range that has since eroded away. The mountains to the west contain sedimentary rocks tens of thousands of feet thick. They record the deposition of limestone, shale, and sandstone along a continental margin that faced a brand new Pacific Ocean 600 million years ago. The fault scarps on the alluvial fan to the south record ancient earthquakes that over a few million years have produced some of the steepest and highest mountain ranges in the American west. More than 11,000 feet separates the summit of Telescope Peak from the valley floor.
The salt and clay of the valley floor record two million years of climate change. Dry warm periods alternated with colder glacial ages that sent meltwater coursing down the Owens Valley, through China Lake, Searles Lake, Panamint Lake and finally into Lake Manly, the freshwater lake that once filled Death Valley to a depth of 500 or 600 feet. Mineralized lake deposits cling to the cliffs above Badwater.

Standing for a brief moment in the middle of nothingness can bring the incredible history of the Earth into sharp focus. But it's not long before our schedule tears us away from the solitude of the moment and we climb into the vehicles and move on towards the comfort of camp, and bathrooms, and dinner. In 1849, a band of travelers had a completely different experience. They were stranded in the valley for several months, having traveled an untested route to California's gold fields. Although only one of their party succumbed during the ordeal, the reputation of Death Valley as a dangerous place was set in stone. The dangers can be real.

In a picture, or in a vehicle, the road looms large. It fills our field of vision, giving us the illusion that humans have somehow conquered this landscape. But it is an illusion. We are not in charge, and all it takes to find this out is the smallest of problems. An overheated radiator. An oil leak. A miscalculation of the mileage in a rental car that is now out of gas. There's no phone service. Even the GPS is sometimes a problem out there. People have been stranded on old mining roads that aren't patrolled regularly. Death Valley didn't necessarily deserve the name it was given in the beginning, but death is no stranger to this place.

It is the hottest and driest place on the continent. It is indeed the hottest place in the world. But in the right season, Death Valley is a delightful place to visit. And it is one of the best places in the world to learn geology in the most dramatic way possible. And  a place where one can learn the value of solitude, for a little while at least.