Friday, February 27, 2015

Barren Cliffs Reveal a Rich and Violent Past: Red Rock Canyon State Park


Deserts have such a fearsome reputation around the world, but deserts can be both beautiful and at certain times of the year a pleasant place to visit. The dry lands of the American Southwest are no exception. For geologists, the treat is made better by the marvelous exposures of barren rock that tell stories of the past when the landscape was very different. This is one of those places: Red Rock Canyon State Park in California. We paid a visit on our way to Death Valley a few weeks ago.
The Garlock fault cuts across the boundary between the Basin and Range province and the Mojave Desert, forming a high linear ridge called the El Paso Mountains. Erosion has stripped away the alluvial cover, exposing the underlying continental sedimentary rocks. The rocks, candy-striped in tones of red, pink and white, formed in a deep basin between 12.5 to 7.5 million years ago, accumulating to a depth of more than a mile. The sediments include arkosic sandstone, siltstone, shale, along with volcanic ash and lava flows recorded several dozen eruptive events. The environment was perhaps semiarid, but certainly wetter than the current day. The fossil record suggests an Upper Sonoran paleobotanical zone, with Black Locust, Mexican pinyon pine, cypress, California live oak, red-root, acacia, desert thorn and palm. Similar plants are found today in the high mountain ridges between San Jacinto and Santa Rosa Peaks in southern California (a region I explored often in my youth).

The steep cliffs have attracted filmmakers for decades, making appearances in all manner of movies, including a lot of westerns, and one of my favorites, the opening scenes of "Jurassic Park".  But instead of dinosaurs, paleontologists have discovered a treasure trove of late Cenozoic mammals, reptiles, amphibians, and birds. More than 100 species have been found thus far.
What kinds of animals lived in the western North America around 10 million years ago? It was a diverse ecosystem with many unexpected species for those who think that deer, antelope and buffalo cover all the bases. Thanks to David Whistler, we have a rather comprehensive list of the animals who lived here.

On the open plains, one would have seen two different rhino species, ten species of horse, four kinds of camels, three antelope species, two elephant-like gomphotheres, vultures, two large land tortoises, pika, two ground squirrel species, deer mice, and rabbits

In the brush covered woodlands, one would have found two oreodonts (extinct sheep-like animals), peccary, three-toed browsing horse, short-legged camel, ringtailed cat, skunk, two weasel-like animals, wolverine,  four distinctly different spiny lizards, night lizard, rosy boa, racer snakes, hedgehog, chipmunk, two gopher-like rodents, two different pocket mice, a bat, three small perching birds, mole, four different shrews, a small, rear-fanged snake, and two alligator lizard species.

This rich selection of plant eating animals represented a huge source of walking protein, so there were predators, lots of them. There were six different species of canids (ancestors to the wolves, foxes, and coyotes), a very large bear-like animal, and three large ancestors to the cats including a an early form of sabertooth.
We spent our time learning the basics of stratigraphy, practiced a rudimentary form of geologic mapping, and interpreted the environment of deposition from the nature of the sediments exposed in the cliff. I wandered between groups of working students, answering questions, but my eyes kept ranging across the cliffs, thinking how incredible it is that we live in a time when we can discern the past history of our planet, and in so doing, understanding how we came to be. We are both a part of the Earth's ecosystem, and yet exist outside that ecosystem (for better or worse).

This rich variety of animals in Miocene time occurred because the climate provided rich sources of food, and diversity of the ecosystem was the result. Today, if a climate is not to our liking, we alter the ecosystem to our own ends. We build our shelters, we travel in little cocoons with air-conditioning and stereophonic sound, and we import vast amounts of resources and fuels to maintain our chosen lifestyle. We tend to ignore the other elements of the ecosystem where we live and visit. We don't embrace our environment, we cut ourselves off from it. It's when I'm in a place like Red Rock that I am reminded of where we come from, our ultimate heritage. We are children of the Earth. And there are limits.

Thursday, February 26, 2015

A Different Kind of "Snow" in California, and a Coming World of Hurt


 There is a different kind of snow falling in California right now. It might look vaguely like that cold stuff that has been falling back east, but the resemblance stops at "white". The almond orchards of the Great Valley have been blooming for the last two weeks or so, and the flower petals are starting to fall to the ground as the buds break out into an explosion of green (green leaves now, and green piles of money later).

The almond blossoms are one of the earliest fruit and nut trees to bloom. The pink peach blossoms are just getting started. Things look great right now. The valley floor is green with grass and the ground is moist, because here in the valley, our rainfall totals are actually ahead of normal in some places. In Modesto so far this year, 10.70 inches of rain has fallen, when 8.45 inches is normal. Last year at this time, we had received a paltry 3.26 inches.

So this is good news, right? Not really. It's good that the orchards didn't need a February "drink" from the irrigation system. It's good that the ranches in the foothills have some of the best grazing conditions in a couple of years. But it won't last. The normal rainfall in our valley was not matched by normal precipitation in the Sierra Nevada, and that is where the precipitation counts. The snowpack in the Sierra is barely a quarter of normal right now, meaning very low runoff in the spring, and almost no irrigation water available for the hot summer months.
We are in a world of hurt. The state is in the fourth year of drought, and there are just not a lot of alternative sources of water to fall back on. We've used way too much groundwater, and it isn't being replaced at all. What are we going to do?

These are hard questions, and they will have to lead to some hard choices. In the meantime, I'm going to enjoy my very colorful commute through the blooming fields and orchards. Spring is always a time of hope and rebirth, and there are still six or seven weeks left in the rainy season. Who knows what could happen?

Sunday, February 22, 2015

Defining Irony: Welcome to One of the Few Parts of California Not Suffering Extreme Drought

The bottom of Death Valley is the driest place in North America, and the hottest place in the world. It might stand to reason that it is a place that withstands the effects of California's horrific four-year drought, which is true, but it's not necessary this year. Death Valley is one of the few parts of the state that is running close to normal in the precipitation department.
Source: http://droughtmonitor.unl.edu/Home/StateDroughtMonitor.aspx?CA
In fact, based on what we saw on our trip to Death Valley last week, this may be a very good year for wildflowers. There were some good storms in December that dropped around an inch of rain in the region, and a later storm dropped another half inch, giving a jump start to seedlings that were starting to grow. An inch and a half constitutes a near-normal rain year in Death Valley!
Photo by Mrs. Geotripper

There were green shoots covering many of the slopes in the Mojave Desert and Death Valley when we visited on the 13th through the 16th. Only a few of the flowers had bloomed, but another week or two and the desert should be coming alive with color.
Sand Verbena on an alluvial fan below Jubilee Pass in southern Death Valley
It's fairly rare for us to see a true flower show on our mid-February trips, but conditions were extraordinary in 1997 and 2005, and I will never forget the color explosion we saw at those times. But enough flowers were present to keep things interesting for us when we weren't observing the rocks.

My guess? Arizona Popcorn Flower

I am not at all good at flower identification, so I expect my good friend Jon Mark Stewart will quickly correct my mistakes. He is the author of Mojave Desert Wildflowers and Colorado Desert Wildflowers, two indispensable guides for desert travelers and flower lovers.
My guess: Yellow Peppergrass
We saw a fair number of flowers at Red Rock Canyon State Park in the Mojave Desert, including the Popcorn Flower and Yellow Peppergrass (above). Red Rock is one of California's gems, familiar to many because of its use as a movie set for all manner of westerns, and at least one "recent" movie: Jurassic Park.
I have no idea...

One of the best early season flower sites in Death Valley is the alluvial fan that extends down to the valley from Jubilee Pass at the south end of the valley. Although the road is paved (it travels from the village of Shoshone to Badwater and on to Furnace Creek), it is far less used by tourists and is usually quiet. We make several important geological stops along this stretch, including a traverse of some of the formations of the Late Proterozoic Pahrump Group. The rocks are around a billion years old, and record the continental divergence that eventually produced the Pacific Ocean.
My guess is Little Gold Poppy

The Sand Verbena and poppies were in evidence, as well as the first outliers of the Desert Sunflower aka Desert Gold. This is a site where we have seen incredible flower displays.

I would dearly love to reach Death Valley in another week or two. Darn work and all that!

The picture below was most certainly not what we saw last week. It dates from 2005 when prodigious amounts of rain (and snow!) fell in the Death Valley region, including a lot that fell on us during our trip. Even at this, the season was early and more flowers bloomed in later weeks. It was quite a year.


Saturday, February 21, 2015

Are There No More Sacred Places? Desecration at the Grand Canyon

The Grand Canyon of the Colorado River, close to the proposed site of a desecration.
I encourage you to read a story in Smithsonian, found here:  http://www.smithsonianmag.com/arts-culture/who-can-save-the-grand-canyon-180954329/?no-ist. And remember the name of a corporation: Confluence Partners LLC, a Scottsdale, Arizona-based investment group. This is a company that feels it has the right to profit by desecrating our national treasure. The company proposes to build a billion dollar complex on the east rim of the Grand Canyon. But not just on the rim. They propose to build a tramway with the capacity to move 10,000 people a day to the bottom of the Grand Canyon to where they intend to build restaurants and curio shops on lands that are sacred to many people.
Truly a confluence: Muddy water from a flooding Little Colorado River mixes with the relatively clear green water of the Colorado River.
I am sadly reminded of the proposal in the 1970s to build a tramway from Glacier Point in Yosemite to the floor of Yosemite Valley. A tram that would have been visible from all over the valley. That proposal was eventually scrapped, but I am truly worried about this one.

I really wonder if anything is sacred anymore. After all, the Liberty Bell is just a piece of broken metal. Why don't we cordon off a corner of it and put in an electronic rolling ad? It would make lots of money for someone. Let's gently carve off a corner of the Declaration of Independence and put in a corporate logo, maybe where that egotist John Hancock signed in such big letters. No one will miss it. Let's dig up some of the dead bodies in Gettysburg and put in a fast-food joint so more people can be well-fed while learning their history (as far as I know that's maybe happened already; I haven't been there). Really, who are we to say whether a small group of investors should be able to profit from the destruction of something that is holy to a great many people?
The Nankoweap Ruins a few miles upstream of the proposed development.
For a century since the designation of Grand Canyon as one of the most important of our national treasures we have managed to keep the lands below the rim inviolate. We've turned away proposals to build dams and we've said no to roads (a single gravel road reaches into the western Grand Canyon where rafters can leave the river). There were a few mines, but those failed long ago. Today the Grand Canyon is under assault: besides this awful proposal, there is a bought-and-paid-for (by the home-building company) city council in Tusayan at the South Rim of the canyon attempting to allow the building of 2,500 homes. With no permanent water sources besides groundwater, which is in limited supply. There are proposals to mine uranium right up to the borders of the park. And what drives it all? Money. Money, and more money. Someone profits in a big way, and we all lose something precious. They can argue all they want, until they are blue in the face, about the merits of their projects, and how they will benefit so many people. If they are truly so altruistic about their motives, I am sure they'd be willing to build their projects at cost with no profit. Right?
The Hopi salt mines in the Grand Canyon
The Grand Canyon is a sacred place. It is the place from which many human beings entered into this world, including the Hopi and Zuni people. It is one of the precious places where Americans learned the value of something besides money when they established a national monument, later to become a park. As we enter into a enter a future in which the oligarchy can do whatever they please to increase their profit margin, we need to hold onto these precious places, and expand them, not shrink and defile them.

Joni Mitchell, bless her, wrote and sang Big Yellow Taxi:

They paved paradise
And put up a parking lot
With a pink hotel, a boutique
And a swinging hot spot

They took all the trees
Put 'em in a tree museum
And they charged the people
A dollar and a half just to see 'em

Don't it always seem to go
That you don't know what you've got
Till it's gone
They paved paradise
And put up a parking lot

The Colorado River a short distance upstream of the confluence with the Little Colorado River.
What can be done? I don't entirely know, but a good place to start is here: http://savetheconfluence.com/

Thursday, February 19, 2015

You Think Some Fish You Caught Was Tough? How Does it Stack Up Against This One?

What kinds of fish are tough? Some Marlin that you spent a couple of hours trying to reel in one time in Mexico? A nice two pound Rainbow Trout that fought hard against your fishing skills in a mountain lake in the Sierra? Some Small-mouth Bass in a reservoir somewhere? I doubt any of them can stack up to this little fish. They were out and about last week during our field trip in numbers I haven't seen in some time.
It's little, hardly exceeding two inches in length. It's certainly not big enough to take a hook. It doesn't have a mouthful of teeth, and it's not a predator (unless you are a diatom or a clump of algae). So how is this a tough fish?
Consider this: it lives in water that can sometimes exceed the saltiness of seawater. By three times. I don't think there is another fish in the world that can do that. And...it can survive in water where the temperature exceeds 100 degrees. Again, I don't think there is another fish in the world that can do that. And one more: the environment in which these fish live can reaching freezing on occasion. No fish that I am aware of can survive such extremes.
But these little fish can.

On top of everything else about this species is the place where it lives, the last place one would even think of looking for fish: Death Valley in eastern California. The hottest place in the world, and the driest place in North America.

Meet the Death Valley Pupfish (Cyprinodon salinus salinus), sometimes known as the Salt Creek Pupfish. It is just one of nine or so species and subspecies of fish that survive in the Death Valley region.
Once you realize that fish are living in Death Valley, certain questions are bound to arise. How can there be water enough for them to survive? How did they get there? And how did there come to be so many species and subspecies ?
The first question is perhaps the easiest to answer. It is true that rain almost never falls in Death Valley, with an average year seeing no more than 1.5-2 inches of precipitation. But Death Valley is the lowest ground in North America, and groundwater flows towards the valley, in some cases from a hundred miles away. Springs and pools form when faults or rock barriers force the water to the surface. These water sources don't depend on the rare rainstorm. It's thought that the water flowing from springs at Furnace Creek or Scotty's Castle has been underground for more than 10,000 years. These stable springs and pools have provided a secure source of water since the end of the last ice age around 12,000 years ago.
But how did the fish get there in the first place? We can say that the fish did not arrive under current climate conditions. River connections between fault basins could only occur during the ice ages when glaciers covered about 30% of the Sierra Nevada. Glacial meltwater drained into the Owens Valley and spilled over into other desert valleys, filling them, and ultimately filling even Death Valley with a hundred mile long freshwater lake. At some point, a connection was made with the Colorado River, and numerous species of fish invaded the ecosystem. But then the ice ages ended.
The vast lakes began to dry up, and the fish were forced to adapt or die out. A number of trout species survived in the cool waters of the Carson, Walker and Truckee River drainages, but in Death Valley, it was only the Cyprinodon species. The one species was forced to survive in different environments, water that might be fresh, salty, hotter, or cooler. The single species diverged into many, much as the finches of the Galapagos Islands did.
During the spring, the Salt Creek Pupfish expand rapidly into the growing flow downstream. Hundreds of fish become thousands, then a million or more. Most of them are doomed when the extreme summer heat sets in and Salt Creek mostly dries up. A few find refuge in the pools and springs at the head of the shallow canyon (a canyon that exists on the floor of Death Valley because of faulting).

Other species of pupfish are more severely limited. The Devil's Hole Pupfish is restricted to a single cavern opening only a few tens of feet across. It is said to be the most endangered vertebrate species in America and maybe the world. There have rarely been more than 300, and at times the population has dipped to barely two dozen. Their continued survival is obviously in doubt.
Toughness doesn't have to be measured by strength or stature. The pupfish of Death Valley show their toughness by surviving in one of the most extreme environments on Earth. They deserve our respect and protection, something we have not always provided. The Tecopa Pupfish (Cyprinodon nevadensis calidae) once lived in two hot springs east of Death Valley. Modifications of the springs in the 1960s to build bath houses destroyed their habitat, and they were gone by 1970. It was the first species to be taken off the endangered species list, not because it was doing better, but because it was extinct. Let's do better with the others.

Tuesday, February 17, 2015

A Little Mystery to Accompany the Moving Stones of the Basin and Range

I'm back from an intense journey through Death Valley National Park and surrounding regions. Much photography and commentary can be expected in the next few weeks, but for today, I'll just lay out a bit of a mystery.
The sliding stones of Racetrack Playa in Death Valley are justly famous, and the mystery of their mode of movement has recently been made clear. But the Racetrack isn't the only place where the stones slide. Bonnie Claire Playa, close to the California-Nevada border, also shows the phenomena. We headed up there on our field studies class. The stones are fascinating, but something else caught my eye while exploring the playa surface.
I don't know what this circle is. It was there by itself, and had no obvious tracks leading to it. Because of its singular nature, I strongly suspect human intervention (SBCC, did you have anything to do with this??). But who knows? If some folks dragged something in a circle, how did they not leave tracks around the edge? Did someone leave a large tire for awhile and retrieve it later?
I even found the circle on Google Earth (below). Again it seems to be all by itself, with no tracks leading to and from.

What do you think is going on here?


Thursday, February 12, 2015

Why it's Nice to Teach in California: It's Field Season All Year!

I'm not sure when or why being in California became a "negative" thing. Sure, we have our urban areas and horrible traffic and air pollution, wildfires, and long droughts. But on the other hand, we have the most diverse set of geological landscapes to be found anywhere on the planet. One can quite seriously work on a tan at the beach, jump in a car and go skiing, and then slide down a sand dune in a desert all in a single day. And for us geologists who teach? We have the longest field season possible! When the last field trip of the fall semester ended, it was mid-November. We had a pleasant warmish day in Pinnacles National Park. Then there was the long, long winter grind. There was that month in December when we got all the rain. Then there was the driest January in our recorded history. And now, in mid-February, it's field season again!
This afternoon I will be taking a class on the road for the next five days, exploring the lands in and around Death Valley National Park. Temperatures are expected to be in the 70s or low 80s. I'm looking forward to being on the road again!
I'm not gloating about those of you who have been inundated in snow. It's not an easy time, and we have our problems of a different nature. The drought is very serious. But I still have to say that I don't understand people who think California isn't a nice place to live. To a geologist, it is paradise!

Web access will be pretty limited, so Geotripper will be back next week...

Wednesday, February 11, 2015

Tenure-track Instructor of Chemistry position at Modesto Junior College

It's not geology, but if there are any great chemistry professors out there who've been impressed with what I've been writing about our incredible Science Community Center, we might have a place for you here. The college will be hiring for a tenure-track position at Modesto Junior College in California's Great Valley. Information can be found here: https://yosemite.peopleadmin.com/postings/1474.

The school is a nice environment to work, with new facilities and some great fellow professors. There are two positions for Instructors of Mathematics (although they'll be on the east campus). Check for other openings at https://yosemite.peopleadmin.com/.

Monday, February 9, 2015

The Sierra Beyond Yosemite: Another Caldera near Mammoth Lakes? Don't Worry About This One...


In the 1980s and unfortunate series of events led to conflict in Mammoth Lakes between geologists concerned about a possible volcanic eruption, and civic leaders and business people worried about their economy and profits. The conflict was exacerbated by irresponsible reporting in the national media. The problems would have been trivial had the volcano actually erupted, but in the end the magma cooled to solid rock at a depth of 7,000 feet or so.
Volcanic events of the last 8,000 years in the eastern Sierra Nevada, from interpretive display at the Mammoth Lakes National Forest Visitor Center
The possibility of volcanic activity in the Mammoth Lakes/Inyo Craters/Mono Lake area is very real. Studies show a dozen or more volcanic events in the last thousand years, and the region is constantly shaken by earthquakes, and riddled with hot springs and steam vents. Things have been mostly calm in recent years, and the warning stage is currently green. The Long Valley Caldera is currently at rest, but hot magma still exists at a depth of three or four miles.

As noted in some of my previous posts, the Long Valley Caldera exploded in apocalyptic fury about 760,000 years ago, releasing some 150 cubic miles of ash into the atmosphere. As the eruption evolved, the Earth's crust collapsed into a massive hole 20 miles long, 10 miles wide, and as much as three miles deep. Probably the last thing anyone would want to find out is that a second caldera exists in the region. But it's not anything to worry about. It went extinct around 100 million years ago in the middle Cretaceous period.

Try to imagine what it is like at a depth of two miles or so in the present day Long Valley Caldera. When the crust collapsed during the climactic eruption a hundred million years ago, huge chunks of rock hundreds, even thousands of feet across fell into the mix of magma and ash. And a great many dinosaurs perished (now that's a thought, but this was a much more local event, not the K/T extinction). A great deal of time passed. Plutons of molten rock intruded the old caldera, cooling slowly to form a granite-like rock, and metamorphosing the older volcanic rocks into slate, schist and greenstone. Even more time passed, and tectonic activity caused the crust to rise many thousands of feet. Erosion stripped away the overlying rock, and the depths of the ancient caldera were exposed to the air, water, and eventually, glacial ice. What had once been the deep interior of a gigantic caldera now stood as high castle-like cliffs. That is the story of the Minarets, seen in spectacular fashion from Minaret Summit just a few miles up the hill from the Mammoth Lakes ski resort.

The rugged ridge of the Minarets and the high peaks of Mt. Banner and Mt. Ritter are not actually on the eastern crest of the Sierra Nevada. They lie a bit to the west of Mammoth Mountain and the headwaters of the west-flowing San Joaquin River lie between the two ridges. The dark peaks of metamorphic rock have always contrasted strongly with the "usual" granite of the Sierra high country.

I once had a marvelous adventure in the Minarets. Decades ago, I was looking for a post-high school adventure, and ended up walking most of the John Muir trail. We tried to follow a few alternate routes in some places, including an attempt to make a cross-country climb over the pass above Iceberg Lake at the base of the Minarets. Unfortunately the lake was living up to its name, and was still frozen over. The pass above was covered in snow, and we had no equipment to surmount the obstacle. We had to backtrack quite a few miles to catch an alternate route. Just about then, our mosquito repellent ran out, so we more or less ran, arms waving at the swarming insects, ten miles or so to Reds Meadow and Devils Postpile. The Minarets had totally rebuffed our efforts to pass through. We took an alternate route that involved hitchhiking to Mammoth Lakes, consuming hamburgers, and following a much easier trail past Duck and Purple Lakes.

I've wondered why the Minarets were never incorporated into nearby Yosemite National Park. I strongly suspect that the metamorphic rocks had mineral plays and potential mining claims. I've heard (but can't confirm) that a large body of magnetite somewhere in the Minarets screws up attempts at orienteering with compasses. In any case it's a protected wilderness today, and a spectacular place to view some of the more unusual rocks to be seen in the high country of the Sierra Nevada. And there aren't any active magma chambers underneath.