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Where are the Ten Most Incredible Places You've Ever Stood? My Number 4: What is it like to be the first person ever to see a cavern?

May 8, 2014, 12:36 pm
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Can you imagine flashing a light in a dark corner of a cavern, knowing that you are the first human being ever to lay eyes on the formations? I haven't had that privilege in my life, but I have found two or three places where I can imagine what the experience was like. Most of the caverns that are accessible to amateur spelunkers like myself have been long known and rather completely explored. Unfortunately, most of them have been severely vandalized, and the early use of torches for light left soot deposits on the formations. It is a rare treasure to see a cave where damage has not yet happened. Such caves in my experience include California Caverns near San Andreas, California,  Black Chasm Cavern near Jackson, California, and the subject of today's post, Kartchner Caverns near Benson, Arizona.
Many of the speleothems are still active; there are water droplets on many of the soda straws

The "Ten Most Incredible Places I've Ever Stood" series has been a series of hard choices. This one made the list because of the shock and the awe, the way the cavern made my jaw drop as I stepped in. It is an experience unlike any other that I've had while underground. There is a difference between even a well-protected cave, and one in which whole areas have never been touched by a human being. The floor of one of the large rooms was covered with mud, and it was clear from the trackway above that only one trail through it was ever made, in order to put in a light source. The rest of the room remains as it was discovered.
How incredible is it that some of the soda straws that fell are still standing in the mud?

The discovery and visitation of any cave causes irreversible changes. Kartchner Caverns were discovered on private lands in 1974 and the people who found them were concerned about preserving the original cave environment. The cave was at nearly 100% humidity, and opening it to the desert environment would have dried it out. Such changes in humidity can adversely affect life in the cave and stunt the growth and development of speleothems (cave decorations like stalactites and stalagmites). And yet the caves were spectacular. Was there some way of preserving the caves while making them accessible to the public?
The discoverers hit on an audacious solution. Through a series of delicate and secret negotiations, the owners of the land agreed to sell the lands containing the cave to the state of Arizona to be developed as a show cave, but to be developed in such a way as to preserve both the features and the climate inside the cave (many of the legislators didn't know what or where the park was when they voted for it). They preserved the humidity of the cave using a series of unique airlocks. Pathways were constructed with a minimum of disruptions to the original configuration of the cave. It took 25 years from the time of discovery to the opening of the park to the public in 1999.

There was one catch. Nothing goes into the cave with the visitors. No food, no water, no backpacks...and no cameras. As you might expect, I live for photography and this for me was a hard restriction. In 2005, though, I got the opportunity of a lifetime: as part of a fund-raiser for the park's foundation, they had a photography day, and the National Association of Geoscience Teachers made arrangements for us to take part. I was going to be given access to the cavern to photograph to my heart's content. To be sure, I had to sign a waiver of commercial rights, and the images that you see in this post today are protected and cannot be sold or used in any way.
Perhaps the most incredible stalagmite/column I've ever seen
What a wonder it was to step into a cave that appeared the same as it was on the day of discovery! The airlock closed behind me and although the temperature was only 78 degrees, it felt much hotter because of the intense humidity. The passageways were dimly lit and it took some time to develop my night vision. But moment by moment the cavern came into focus. It was simply stunning.

I wandered from passage to passage lost in the moment. It was nice not having a guide (staff were stationed throughout the cave to answer questions and keep an eye on things), but it was also nice to be exploring a pristine cave knowing I wasn't doing major damage just by being there. Exploring a newly discovered cave means leaving muddy footprints and accidentally destroying delicate formations underfoot, or leaving trails in the mud. I remember thinking that the experience was something like being in a museum, but I thought that in a good way: the resource was being protected, and yet hundreds of thousands of people could see and enjoy it. 
Some marvelous "helictites", otherwise known as stalactites on LSD.
Although I can't be mistaken for a professional photographer, I learned long ago that photography in a cave is always tricky. There is no "natural" look to a cave except total darkness, but a camera flash steals perspective and washes out delicate differences in color and shading. I used the ambient lighting to maintain some depth to the photos. That meant standing very still for longer than usual exposure times (tripods weren't allowed at the time). 

Flowstone refers to speleothems that result from water seeping out of cracks in the walls of a cavern. Over time gigantic mounds build up that resemble ice cream sundaes. Kartchner is full of spectacular examples.

I'm not sure what to make of the features below. There are some nice soda straws, which are so delicate that they are the first to be broken off in unprotected caves. The spiky things are the beginnings of helictites, which tend to ignore gravity, growing instead under the influence of water pressure from the interior of the "confused" stalagmites.

Below, one can see a spectacular column in the foreground, and some marvelous draperies in the upper left background. None of the features were broken off, and none were vandalized. I can barely describe what it is like being in such a place. Every minute in the cave was precious. I know there is an argument about worrying over technology in situations like this, and that one needs to live in the moment, reveling in the experience of being, but I actually find caves disorienting. Despite all my orienteering skills on the Earth's surface (and people tell me they are formidable) I get lost in caves. I can't remember one room or one decoration from another. Photographs keep me centered, and keep the memories of the moment alive. And I can share them!

I passed a stunning wall of draperies. Time was beginning to run short and I would be needing to leave this fantastical world for the surface before long. I was sweating, dehydrated, hungry and tired. It wasn't difficult getting around, but the humidity gets to you eventually, draining your energy. I started to head for the exit chamber and the airlock to the outer world.

There was one last close-up of a moist, almost glowing surface of some flowstone, and then I was out the door to the world of light and fresh air. The contrast was shocking. Caverns are incredible places, but they aren't really a human environment. I can understand how the first explorations of caverns could awaken our ancestors to the ideas of shadow-worlds with their demons and nightmares. Hell was presented as an underworld of fiery pits and eternal torment. But in a different context, caverns have been a place where dreams come alive. I think of the spiritual awakening of an initiate in a deep cave thousands of years ago encountering the drawn images of animals and people on a cavern wall seeming to run and play in the flickering light of a burning torch. Wandering through a pristine cave in the present day brings us face to face with a fascinating world that is not completely apart from us. The deep hidden parts of caves may not be a human environment, but much of our early spiritual and cultural development derived from living and exploring the outer edges of the underground environment. Caves are places where magic seems possible.

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Where are the Ten Most Incredible Places You've Ever Stood? My Number 3: Standing over Dante's Inferno in the Broken Lands

May 10, 2014, 1:38 am
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The Panamint Mountains and Telescope Peak, the highest part of Death Valley National Park, as seen from Dante's View..
Death Valley is the hottest place on planet Earth.  Furnace Creek recorded a temperature of 134 °F (57 °C) in 1913. With the dethroning of the improperly recorded temperature in Libya from 1922, this is the hottest officially recorded temperature in world history. Badwater, a dozen miles south of Furnace Creek at the deepest point in the valley, is often a few degrees hotter. The hottest overnight temperature ever recorded, 107 °F (42 °C), was measured here on July 12, 2012. That day, the average temperature was 117.5 °F (47.5 °C), the world's hottest 24-hours on record.

Hot temperatures are an interesting feature of Death Valley National Park, but the park is much more significant for other reasons. It contains a wider range and variety of rocks than any other park that I know of. I have been chronicling our February journey to Death Valley over the last few months in a series called "Out of the Valley of Death", and today's post is a confluence of the two series that I've been working on. Dante's View was our next stop after exploring the interior of an upside-down mountain at Titus Canyon, and it makes number three on my list of the Ten Most Incredible Places I've Ever Stood.

The Black Mountains of Death Valley are one of the most rugged mountain ranges in existence. They rise 6,000 feet almost straight up from the lowest part of the Death Valley graben and are practically devoid of trails or roads. The thought of climbing the mountain front near Badwater is as daunting a challenge as I can imagine. The Proterozoic metamorphic rocks are highly deformed and internally sheared by intense faulting, making for a highly unstable climbing surface. But there is a way to the top of the range. A paved highway winds up the other more gentle eastern side of the mountain range, reaching Dante's View at an elevation of 5,476 ft (1,669 m). The overlook is directly above Badwater, more than a mile below at -282 feet ( -86 m). It has one of the most incredible views to be found in any national park.
Frank DeCourten called the Basin and Range province where Death Valley is located the "Broken Land", and the description is apt. From Dante's View, thousands of square miles of land are visible as range after range marches off into the distance. In the last few million years crust in this region was stretched beyond the breaking point, and it broke into countless grabens (fault valleys) and horsts (fault-block mountain ranges).  River drainages that once reached the sea do so no longer, and water leaves the region only by evaporation. The region is sometimes called the "Great Basin" despite the multitude of mountain ranges. Death Valley is the lowest of the low, the ending point of numerous desert washes and the Amargosa "River" that sometimes in wet years has water.

At Dante's View, one's attention is most often drawn towards the salt pan of Death Valley, the lowest land in North America (in the picture above). It is quite a sight, and so alien-looking that it stood in as the location of Mos Eisely in the original Star Wars. Obi-Wan Kenobi and Luke Skywalker stood here, looking at the spaceport and mentioning that "You will never find a more wretched hive of scum and villainy". The salt that covers the valley floor to a depth of hundreds of feet was washed out of the marine sediments that make up many of the mountains in the region, and from the rain itself. Water flows into the salt pan and evaporates, leaving behind the salt and other minerals, including gypsum and calcite.
The view from Dante's encompasses, well, the entire compass. To the south (above) the Black Mountains continue for several miles, including two of the gigantic "turtleback faults". The rocks are some of the oldest in the western United States at 1.7 billion years. The dark metamorphic rocks gave the mountains their name. Although the slopes are not as hot and dry as the valley floor, it is still a tough environment for most plants. The mountains are as barren as any I've ever seen.
To the north (above), the Black Mountains include younger volcanic rocks dating from the middle and late Cenozoic era. They include the Artist Drive Formation, and the ancient lake and valley sediments of the Furnace Creek and Funeral formations. The Grapevine Mountains rise in the far distance. They are composed of thick sequences of marine sediments dating from the Paleozoic era. The farthest ranges are more than 60 miles away.
To the east (above), range after range culminates in the snow-covered Spring Mountains above Las Vegas (did you know you can ski near Las Vegas?). The highest peaks exceed 12,000 feet. Some of the water that accumulates on the slopes of the Spring Mountains travels underground through the intervening mountains to emerge as springs in Death Valley.
One of the most amazing things about the view from Dante's is how different it would have appeared 20,000 years ago during the last of the ice ages. Meltwater from the glaciers of the Sierra Nevada drained into the Great Basin, filling one valley after another until it spilled over into the Death Valley graben, forming a 600 foot deep lake more than 100 miles long.The lake left behind shorelines and terraces in what is currently the driest place in North America, and at least four species of native fish which still live in isolated springs around the park.

Water still accumulates in the Death Valley graben on occasion. Lakes were there in 2005 and 2010, but the same wet weather that filled the salt pan with water also wreaked havoc with the road to Dante's View and it was closed, so I have no pictures of the lake from above. This one from the valley floor will have to do.

Some of my choices for the "ten most incredible places" involved lava, or fossils, or significant historical and geological events. I chose Dante's View for sheer grandeur. From the high vantage point of Dante's, one gets a sense of being on top of the world, a world that is sometimes an inferno, and certainly broken up. There are few places on Earth like it.
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Brad Paisley Lets Out His Inner Rock...Again

May 11, 2014, 3:01 pm
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See the Raiders of the Lost Ark on the Big Screen (and get a treasure of your own) on May 15

May 12, 2014, 2:16 am
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This is a note of local interest to our readers in the Modesto region...

The Geology and Anthropology Clubs at Modesto Junior College invite you to an evening of thrills, chills, and death-defying action, and that's just the Silent Fossil and Mineral Auction! Beautiful examples of geodes, petrified wood, dinosaur bone, fossils, crystals and rare minerals will be offered for purchase. Proceeds will go towards scholarships for students in the field studies program in Geology and Anthropology at Modesto Junior College.

The auction will be followed by a special showing of Indiana Jones and the Raiders of the Lost Ark, the classic 1981 adventure produced by George Lucas and directed by Stephen Spielberg, starring Harrison Ford and Karen Allen. If you have never seen Raiders of the Lost Ark on the big screen, you've been missing out. The State Theatre is one of Modesto's treasures, and it is a marvelous venue for watching classic movies.

The students of the geology and anthropology programs at Modesto Junior College have been working hard to assist their fellow students to attend the Summer Field Studies trip to Canada and the Pacific Northwest this summer, and this is their biggest fundraising event of the year. Come out for a great time, and come home with a treasure of your own!

Date: Thursday, May 15 at 6:30 PM (film at 7:30 PM)

Location: State Theatre, 1307 J Street, Modesto 209-527-4697

Donation: $10 Pay at the door or get tickets in advance from Garry Hayes (575-6294) to guarantee a seat. Make checks out to Modesto Junior College Geology Club.

On behalf of the students of MJC, we thank you for your support!

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

May 13, 2014, 12:40 am
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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??


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Where are the Ten Most Incredible Places You've Ever Stood? My Number 1: Roads End at the Edge of the World

May 15, 2014, 12:47 am
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There's an empty quarter within the bounds of the lower 48 states. It's a vast area, a swath of land across southern Utah and northern Arizona where towns are few, and the vistas are wide. It's bounded by Blanding on the east, Mexican Hat and Kayenta to the south, and Lake Powell off to the west. Outside of these few villages there are some reservation lands and ranches. There is a national monument (Natural Bridges), and a national park off to the north (Canyonlands), but mostly it's uninhabited Bureau of Land Management land. In other words, lands held in trust for all the people of the United States.

I've been going through a list of the ten most incredible places I've ever stood, and so far in this series we have explored the Alaka'i Swamp of Kaua'i, Hawai'i, the lava flows at Pu'u O'o on the Big Island, Frame Arch in Arches National Park, the moment of global death in Gubbio, Italy, and the Burgess Shale of British Columbia. There was Siccar Point in Scotland, Kartchner Caverns of Arizona, Dante's View in Death Valley, and Hance Rapids on the Colorado River in the Grand Canyon. I also cheated a little and insinuated that Glacier Point in Yosemite was one of the ten (which it is, even if all of these add up to eleven; didn't you all see "This is Spinal Tap"?). Some of these I chose because of their geological significance, and some because of their incredible scenery. A few were chosen from sheer emotion and personal spiritual reasons, and that is also the motivation for my number one choice. Not many people know of the place. It's not a national park or monument, and the geology, while interesting, is not exceptional. It's in the center of the empty quarter of Utah on the edge of Cedar Mesa. It's called Muley Point.


Standing on the edge of the world at Muley Point, one looks down several thousand feet into the mysterious gorge of the San Juan River, one of the major tributaries of the Colorado River. The canyon is an intricate twisting maze of curving gorges called entrenched meanders. The river once flowed as a meandering stream channel over a flat plain relatively close to sea level. When the land rose, the gradient of the river increased, but the water was trapped in the meandering channel, so the curve was preserved as the river cut ever deeper (below).

The rocks making up the cliffs are part of the Cedar Mesa Sandstone, a Permian-aged unit that preserves some coastal sand dunes, and the occasional bone or track of some pre-dinosaurian reptile like Dimetrodon.
Entrenched meanders of the San Juan River below Muley Point

In the distance beyond the canyon of the San Juan stand the buttes and mesas of Monument Valley, the scene of so many iconic western movies (below). The valley is administered as a tribal park of the Navajo people. The farthest horizon reveals the margin of Black Mesa, the heart of the Navajo Reservation and the home of the Hopi Nation as well. The spiky monument in the far distance just left of center is Agathla's Needle, the core of a deeply eroded volcano. This volcanic neck, or diatreme, is similar in age and composition to the better known Shiprock a few miles away in New Mexico.

The view to the east extends across the Raplee Anticline to the Chuska Mountains of New Mexico, and the Rocky Mountains of southeastern Colorado. The scene below is taken from the top of the Moki Dugway on Utah Highway 261, the precarious road that provides access to Cedar Mesa and Muley Point.
The view east from the top of the Moki Dugway, the spectular road that provides access to Muley Point

North from the Moki Dugway one can see the deeply incised edges of Cedar Mesa. Looking at this barren desert landscape, it is hard to accept that Cedar Mesa was once part of the "fertile crescent" of the American Southwest. An arc of land extending from Mesa Verde to Cedar Mesa was in the "sweet spot" elevation of being not too hot and not too cold and having just enough precipitation to produce high yields of maize, squash and beans. It was a thriving agricultural region for the Ancestral Puebloan people for hundreds of years. Most of the surface of Cedar Mesa was under cultivation, and thousands of archaeological sites dot the region (unfortunately making it a target for illegal pothunters). The Puebloans moved on eight hundred years ago, and the mesa has been more or less deserted since then. The juniper and pinyon trees sprouted and covered the ancient corn fields.
Years ago I learned the craft of leading field studies with the staff and crew of Santa Barbara City College, days I remember fondly. We used to take a one-day raft trip down the San Juan River from Bluff to Mexican Hat, and the night before we would spend the night at Sand Island on the river. We would spend a few moments at Muley Point before descending to the hot, humid, and buggy campsite. One year someone pointed out that we were fully equipped to camp anywhere, so why not stay on the rim of Cedar Mesa where the view was indescribable, and the air was fresh and clean, and gloriously free of biting deerflies and mosquitoes? From that time on we camped on the edge of the world. What had been just another spot with a nice view became for me a yearly pilgrimage.

What makes this place so different? It's magic, I think. It is the top of the world, and the edge of the world. One can stand and see a vast region occupied by a mere handful of people, a land that shows little of the damage (at distance anyway) that people can do to a landscape. It's colorful and ever-changing, especially in the light of dusk or twilight. There aren't many places where one can experience the full drama of the Earth through sunset, night and sunrise, and have a completely unobstructed view of the sky from horizon to horizon to horizon.
Usually when we pull into a campsite on our field trips, the students and crew jump out, unpack, and set up their tents and the cooking area. I learned long ago that Cedar Mesa and Muley Point are different. The people emerging from their vehicles disappear. I wander along the edge of the mesa and I find them, sitting alone or in small groups, just contemplating and staring at the scene before them. I often take on the task of preparing the evening's meal just to give them more time to be out there.
I've spent a total of two weeks on the mesa over the last three decades and every night is different. We've seen warm clear days and nights, we've had windstorms (equipments blows over the edge never to be seen again), thunderstorms, and rain.
Have you ever spent an entire night taking in a special place? Have you ever watched the progression of the cosmos over hours and hours of time? We constantly insulate ourselves from the darkness, but there are certain times and places where we can revel in it. There is nothing quite like watching moonlight reach deeper and deeper into canyons below the rim. What had been featureless darkness below becomes an intricate pattern of complex beauty. I've awakened in the early hours of the morning to watch the moon setting or watching the long drama of sunrise. Some nights there are thunderstorms over the Sleeping Ute or Chuska Mountains.The fire in the sky is an incredible sight.

Sometimes there are eerie things as well. Rational people can still feel the echoes of the lives that were played out on this mesa. I've been keenly aware of the spirits that exist in and around the canyons, whether real, or constructs of the imagination. We sat on the edge of the mesa one night nearly thirty years ago and saw mysterious lights. I still to this day don't know what to make of them (and you can be sure that I've watched for their return ever since!). Yet, I've never felt scared or nervous in this place. Just curious.
The morning inevitably comes, and once the sun rises high in the sky, the mesa becomes less mysterious. We are ready for a day of seeking the Ancestral Pueblo ruins that are hidden in literally every side canyon on the mesa. Spending a night exposed to the environment that they called home enlightens our explorations.
It was hard to pick the top ten of my most incredible places, and I couldn't begin to rank them, but I do know that I might not see the Burgess Shale or the Gubbio clay layer or Siccar Point again in my life. They were memorable, and I will always cherish that fact that I got to see them. But I didn't experience them, not in the way that I've experienced the Grand Canyon, Yosemite, and Cedar Mesa.

That's the thing I guess. Any place in this wide world can become the most incredible place you will ever stand. It won't be that tourist destination that is famous worldwide, because those are the places that you visit once or twice and never get to know. The special places are those which you experience in the fullest sense in all kinds of situations and conditions. That's what Cedar Mesa is to me.
So, what has me worried? I was digging through the tons of old topographic maps in the old department as we prepared for the move to the new Science Community Center. And I found a topo map of the Glen Canyon National Recreational Area, and noticed that a small corner of Cedar Mesa extends over the boundary of the GCNRA. Muley Point is "protected"! But in small print were the following words: "Slated for future development". Chilling words, but thus far unrealized. A paved road, interpretive signs, restrooms, and parking lots would ruin this incredible place. I hesitated about even making its presence known, but in the end I did, because unknown places are the easiest to destroy (just ask Glen Canyon). Such places will need friends in the future.

In the meantime, revel in the discovery of your own most incredible places, and if you are ever near the town of Mexican Hat, seek out Muley Point. It's not too hard to find, the road is okay for most cars even if a bit bumpy at times. And don't just look and drive away after a few minutes. Lay out a sleeping bag, find the appropriate rock (you'll know the right one), and let this place fill you. You won't regret it.

PS: After I posted this, Ron Schott let me know he had a 360 degree gigapan of the view from Muley Point. Check it out at  http://www.gigapan.com/gigapans/52566 !
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Checking Out Mount Diablo's Biologic Overburden

May 18, 2014, 12:44 am
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Mt. Diablo is one of California's most spectacular state parks. Rising 3,847 feet above the Bay Area, the mountain is one of the most prominent in the state. It served as the starting point for surveying property line across Central California and Nevada. And it has marvelous geology: thrust faults, ocean crust, Franciscan chert, thick sequences of sandstone and coal, and a rich paleontological record. It also has some living overburden as well.

"Overburden" is a term used for the dirt and rock that overlies some valuable mineral or ore, like coal. Such rock (and all the living stuff on it) is quarried away and discarded. We geologists (and me especially) can sometimes miss the stuff that gets between us and our rocks. On field trips sometimes, I chafe a little when the attention of my students is drawn towards a squirrel or a deer instead of the incredibly important rock exposure that I'm talking about. But sometimes I get distracted too.

I see raccoons fairly often as I drive home across the creek that runs north of my town, but usually at night. Before today I had only one decent photograph of one, but as we got out to explore the Rock City at Mount Diablo, some of our students spied one. He was clearly a camp raccoon, as he didn't seem to bothered by all the cameras that were snapping.
The semester is over at my college, but the Geology Club never managed to schedule a field trip during the semester as is our tradition. Now that finals are over, the stress levels dropped, and our geology students were ready to hit the road and have a bit of fun. We headed west into the Coast Ranges for a tour of California's largest coal mine (and think about that for a moment; did you know that California once had coal mines?). It's called the Black Diamond Mine, and is part of a regional park above the town of Antioch in the Sacramento Delta. That tour was spectacular, and will also be part of a future blog post.

We had time after the tour, so we headed up nearby Mount Diablo. Despite the incredibly dry conditions this year (the state is still suffering an exceptional and unprecedented drought), there were some gorgeous wildflowers around the summit trail.
I don't know wildflowers anything like I know minerals, but I can buy books in the park visitor center! The yellow flower above is endemic to Mt. Diablo, and not too surprisingly is called the the Mt. Diablo Globe Lily ( Calochortus pulchellus).
 The orange flower above is the Wind Poppy (Papaver heterophylla). Below is a Red Larkspur (Delphinium species).
The flower below really caught my eye. It's a Butterfly Tulip (Calochortus venustus). I realized today that I have been visiting Mount Diablo in the summer or fall, and I've been missing some real flower shows of species I've never seen before, including a number of those in the post
I think the one below is a Western Wallflower (Erysimum capitatum), but I accept corrections.

It was a beautiful day in the Coast Ranges!
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Imagine in Your Mind a "Scientist"

May 18, 2014, 2:11 pm
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This is a question I ask my students during the first week of every class I teach. There are consistent responses: "white lab coat", "pocket protector", "test tubes", "eyeglasses". Then I ask "What gender?". They invariably answer "male". And then I ask "What ethnicity?" There is usually a pause, and the answer is invariably "white".

The core image in the minds of nearly all my students, no matter their background, is that scientists are old white guys in lab coats. I just can't imagine where they get such ideas...


There are lots of reasons that people don't imagine themselves as scientists, but the sad fact is that geology in particular has a really poor track record in the education and hiring of people who aren't white or male. I strongly encourage you to have a look at this post from Black Geoscientists:  http://blackgeoscientists.com/2014/05/18/geosciences-in-the-united-states-the-stats/.

"...this “is what geoscience feels like to most black people.” Not most black geoscientists, but most black people. Whether they’re a chef, teacher, writer, nurse, lawyer, or actor there is a widely held (unspoken) belief that geology isn’t for black people. And unfortunately, the statistics turn that belief into a fact."

There is a lot that needs to be done. There are too many big problems in our society to leave just to an army of old white men on the verge of retirement.
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Where are the Ten Most Incredible Places You've Ever Stood? The Runners Up

May 19, 2014, 12:04 pm
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I've noticed that nearly every movie reviewer puts a list of the runners up at the end of their list of the top ten movies of the year. In that spirit, I'm putting up a set of pictures from the places that almost made my top ten list of the most incredible places I've ever stood. As before, there is no particular order to these personal choices. It's a bit like asking which of your children you love the most...
 Number 20: Horseshoe Bend, Arizona
A few miles downstream of Glen Canyon Dam is a huge entrenched meander along the Colorado River. The deep blue color of the river isn't right; the silt has settled in Lake Powell, but it makes for a memorable color contrast. Learn more about Horseshoe Bend here.
Number 19: Antelope Canyon, Arizona
There are hundreds of spectacular slot canyons scattered across Utah and Arizona, and you don't have to pay to get into them, and the noontime tours can be extremely crowded, as in shoulder to shoulder, but there can be no denying that the long beams of sunlight reaching into the darkness of the labyrinth is a spectacular and unique sight. For more views, check out this link.
Number 18: Observation Point, Zion National Park, Utah
The Angel's Landing Trail in Zion is one of the most spectacular hikes in North America, but I can never forget my adventure of climbing to Observation Point on the other side of the valley and looking hundreds of feet down onto Angel's Landing (the Landing is the peak on the lower right). For more information about Zion, check out this link.
Number 17: Inspiration Point, Bryce Canyon National Park, Utah
Bryce Canyon is one of the most intricately eroded landscapes in the world, and the spires, called hoodoos, look otherworldly. Almost as incredible is to walk among the hoodoos below the rim, so here is a shot of the fir trees growing in the impossible environment of Wall Street Canyon at Bryce.
For more information about Bryce Canyon National Park, click here.

Number 16: Captain Jack's Stronghold, Lava Beds National Monument, California
The northern flanks of Medicine Lake Highland are coated in barren flows of basalt from the gigantic shield volcano. Within the flows are miles and miles of lava tubes, long caves left behind as the lava drained out. This was the setting for the Modoc Indian War of 1872-73, yet another tragic story of destroying the culture and lives of a people, in this case so settlers could have more land to graze cows and grow potatoes. It's a haunting place to stand. For more information, click here.
Number 15: The Big Sur Coast, California
A mountain range rises directly from the sea. That's about the only way to describe the incredible Big Sur Coast of Central California. This is a view of McWay Falls at Julia Pfeiffer-Burns State Park. For more details, check out this post.
Number 14: Muir Woods National Monument, California
I read somewhere that Muir Woods is the most heavily visited national monument in the United States, and I understand why. It's one of the few old growth Redwood Forests left anywhere close to the Bay Area, and it is a wondrous place to wander about. The Redwoods are ancient trees, both in individual age (thousands of years), and in ancestry (back to the age of the dinosaurs). More information about this incredible place can be found here.
Number 13: Pinnacles National Park, California
Around 23 million years ago, a volcanic center of five rhyolitic cones erupted on top of the San Andreas fault. The fault split the volcano, and the two halves are separated by 195 miles. At Pinnacles National Monument, the jointed blocks of lava and lahars have been eroded into towers and spires. The High Peaks Trail is one of my favorite hikes in North America. For more information, check out this link.
Number 12: Owens Valley and the Eastern Sierra Nevada
The most incredible wall of rock that I know is the eastern escarpment of the Sierra Nevada, a two-mile high barrier to storms and human travel. No highways cross a stretch of something close to 200 miles of mountain peaks. The Owens Valley is a deep fault trough that once was going to be one of the most important agricultural regions of California, but because of water diversions by Los Angeles, is now a sagebrush desert. Each canyon hides treasures, and I spent much of my youth exploring as many of them as possible.
Number 11: The Great Western Divide, Sequoia National Park, California
My own personal terra incognita, the Great Western Divide is a high sub-range in the middle of Sequoia National Park across the Kern River from the main Sierra Crest. It's one of the last major parts of California that I haven't set foot on, but I've looked in from the summit of Moro Rock. There are lots of places left to explore in my life...
And another Number 11 (because it's my blog and I make the rules): Mono Lake, California
Mono Lake probably belongs on another planet. It's one of the strangest sights in a state filled with strange sights, a lake that is three times as salty as seawater, with a simple ecosystem of basically algae, brine shrimp and brine flies, but the simple combination is a food source for millions upon millions of migratory birds. The edge of the lake is lined with strange tufa towers that formed along freshwater springs.

And that's my highly personal list of the second ten most incredible places I've stood, and it was just as hard to pick out as the first ten! I'd love to hear about more of your favorite places. Put them in the comments, or send me a story that I can post as a guest entry in Geotripper!
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Through the Looking "Glass" and into the Rabbit Hole: A Tour of the Black Diamond Mine

May 21, 2014, 11:27 am
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Coal mining...

Barren open pits, overburden stripped away, ruined rivers, flattened mountain tops. It doesn't have a very good reputation and probably doesn't deserve it. Yet even today it provides a significant part of our energy mix, despite the destructive effects it has on our atmosphere, land, water, and the lives of the miners themselves. A hundred years ago it provided much more of our energy.

California doesn't have much of a reputation for coal mining. During the middle and late Paleozoic, when widespread parts of the eastern United States and parts of Europe were covered by forests, swampls and coastal estuaries, California was pretty much underwater, and no major coal seams ever formed.

The situation was a little different about 50 million years ago. The Ancestral Sierra Nevada, the mountains that formed while granite was cooling deep in the Earth, had been worn away, and the modern Sierra Nevada had not yet begun rising. Large meandering rivers coursed across the landscape, bringing sediments into the coastal complex from sources as distant as central Nevada and Idaho. A shallow sea filled the forearc basin that paralleled the Pacific coast, and along its margins there were beaches and barrier islands, along with coastal estuaries and jungles of tropical vegetation. The river and coastal complex formed a sedimentary layer called the Domengine Formation (in the Sierra Nevada foothills, it is known as the Ione Formation and the Auriferous Gravels). It was here that coal formed in California. It was a low-grade form of coal called lignite. It had none of the quality or energy content of  bituminous or anthracite coal, but it was close to San Francisco, and it was the only coal for hundreds, even thousands of miles. Coal mining began in the Coast Ranges above Antioch in the 1850s, eventually producing four million tons before shutting down around a half century later. Several thousand miners and their families lived in five villages in the immediate vicinity, and dug miles and miles of tunnels into the hills (I've heard of upwards of 200 miles of passageways).

The towns faded away and many of the underground workings collapsed. In the 1920s, a new resource was being mined here: sand. Sand? What in the world for? For glass-making. It turns out that the sandstone of the Domengine Formation is very pure, almost 100% quartz. If you've ever stood on a sandy beach in California, you would know that the sand in the state is usually gray or brown in color because of the many other minerals that are present. It's only sands that have been transported along lengthy rivers and deposited in coastal regions where they would be washed back and forth for millennia that they reach that level of purity. Those were the conditions present as the Domengine was being laid down 50 million years ago. Glass mining took place through the 30s and 40s, and ultimately 8 miles of huge tunnels were excavated. That's a lot of glass bottles...
California paleogeography from interpretive signs at Black Diamond Mines, mapping by Ron Blakey of Northern Arizona University

So it was that last Saturday, the Geology Club at my college finally conducted their semester field trip, two weeks after the semester was done. We headed out to the Black Diamond Mines Regional Preserve, a unit of the East Bay Regional Park District to have a tour. Not a tour of the former towns...we were going underground!
We gathered outside the portal of the Hazel Atlas mine where we met Pat, the mining technician and engineer for the park. He came to work here in 1998 to prepare for the reopening the mines for tours after safety concerns shut them down in 1989 after the Loma Prieta earthquake.
We donned our hardhats, grabbed flashlights, and headed into the main portal. One thinks of mines as dark dank places, and I'll bet they were to the original coal miners, but with lighting and white colored walls of sand, the tunnel was actually fairly bright, at first not really different than walking down a corridor in a factory.
The main adit intersected one of the thinner coal seams in the Domengine Formation. The miners in the 1800s generally followed the seams until they thinned out to a foot or so. The thickest of the coal seams, the Black Diamond vein, averaged 40 inches thick
One can see in the picture above that the layers in the mine slope about 30 degrees. The miners accessed the coal seams from the lower end and excavated their way upward, allowing gravity to do some of the work for them.

Diagram from interpretive signs in the visitor center
The walls of the mine reveal other signs of the depositional environment of the sandstone. In the picture below are some crossbeds, formed in coastal dune complexes.
Farther in, the sand layers broke away to reveal symmetrical ripplemarks, which indicate oscillating waves in shallow water. Although I didn't get good shots, there were trackways of worms in some sand layers, and burrows from crabs or shrimp. Such disturbances of sediment by biologic activity is called bioturbation.
By this point we had gone several hundred feet into the mountainside, and the tunnel turned 90 degrees to run parallel to the surface.
We had reached the main part of the mine, where excavation was done by the room and pillar method, where large chunks of sandstone were left in place to support the ceiling of the mine, in many places 6o feet above our heads. It's not often that I am in underground chambers this big. I almost expected a Balrog to come around a corner ("You shall not pass", he said, wielding his rock hammer like a wizard...)
There were dark unlit pits too. The dark squares on the left in the picture below are rock bolts, drilled into the rock to hold unstable jointed rock in place. Pat reported that chunks of rock do occasionally split off the walls and fall. One of his jobs is to locate such rocks along the main tour tunnel and either stabilize them or pull them down. That actually sounds like fun, even if a bit dangerous.
We had reached the end of the regularly scheduled tour, and found that there is an escape route out of the mines in the event of a collapse. We continued on, following the escapeway, because there was some good geology still to be seen!
We were now following a stope back towards the surface.
We intersected one of the coal seams, and could see why the coal mining was so dangerous. The rock was much softer and incompetent. They occasionally have problems with the coal because it generates noxious gases. When the sand mine intersected with one of the old coal mining passageways, there would occasionally be a spike in carbon dioxide or other gases, and the coal tunnel would have to be isolated to keep the air fresh.
I was surprised by how good the air was. The temperature was about 56 degrees and there was usually a current of air blowing through. It was not at all like some mining tunnels I've been in. I don't think there is any worse feeling than warm stagnant air in a dark tunnel.

Near the exit, we had a view down into the Eureka slope, one of the coal mines active in the 1860s. The picture below doesn't provide the downward perspective. It sloped about 30 degrees or more and disappeared in the darkness below. Visiting a coal mine? Fine. Working in one every day of one's working life? No, thank you. I like the job I have now.

We approached the surface after close to a half mile of walking underground. We had barely begun to explore the intricate boxwork of passageways in the mine. The visitor center occupies a particularly large tunnel at the other opening to the mine (the "emergency exit").
We emerged back into the world of sunlight and blue sky.

Although there are occasional tailings piles of coal here and there, the region has recovered nicely from the mining days, and is a nature preserve today with miles of trails and picnic areas. More information about the park can be found at http://www.ebparks.org/parks/black_diamond. It's well worth a visit!

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Taking in the View from the Bay Area's Devilish "Not a Volcano"

May 23, 2014, 12:30 am
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Mount Diablo looms over the Bay Area, rising 3,849 feet above the coastal plains. The two prominent peaks are miles from any other high mountains, and thus the mountain offers an incomparable view of central California, from Mt. Lassen in the far north to Mt. Dana and other high peaks of Yosemite National Park to the south. Sitting above the Carquinez Straits and the delta of the Sacramento River, it also offers unparalleled views of the Bay Area including the Golden Gate Bridge and the skyline of San Francisco (on non-foggy days). One minor surprise: if you actually stand on the true summit of Mount Diablo, you won't see any of the things mentioned above. It's inside a building (see the picture below).

The monument in the visitor center describes the use of the mountaintop as the initial point for all of survey lines for Central California and Nevada. Any property lines using the township and range system of measurements in the region are based on measurements from the summit that started in the 1850s.
The most prevalent story of how the peak came to be called "Diablo" involves an effort by the Spanish to force members of the local Native Americans into servitude at the nearby missions. Some were hiding out in willow thickets that the Spanish called the Monte Diablo, the "devil's thicket", but the "monte" was later mistranslated as "montana".

Despite the mountain's distinctive shape, it is not volcano. Even though some of the rock making up the mountain is volcanic, it is basalt and related rocks that were once part of the ocean crust, and not something erupted from a terrestrial cone. The origin of the mountain can best be described as ocean floor crust and Franciscan trench deposits breaching the Earth's surface like (oh, geologist friends forgive me) some gigantic Godzilla character in a movie. Described more properly, the rocks from deep in the crust have been thrust upwards along active compressional faults.
A rather narrow and exciting road climbs to the summit of Mt. Diablo, the centerpiece of Mt. Diablo State Park. The summit building contains a visitor center and store, and includes an observation deck. Trails lead out in several directions from the summit, but one, the Mary Bowerman Nature Trail, circles the summit in about 0.7 miles.
North from the summit, the hills drop away rapidly to the Sacramento River and Carquinez Straits, where about 60% of all of California's fresh water flows. 32 of the 35 islands in the delta have subsided to below sea level. They are protected by poorly designed levees that are a century or more old. If a moderate earthquake strikes on one of the nearby faults, liquefaction will cause widespread failure of the levees, and the delta will be flooded with salt water. The California Water Project will be shut down for many months while the delta is slowly flushed out. The implications for water deliveries to the San Joaquin Valley and Southern California are frightening.
An odd sight is visible just to the north, the large open pit mine called the Mt. Zion quarry. The basaltic diabase is some of the oceanic crust mentioned earlier. It is a tough and stable rock, useful for breakwaters, road beds, and railroad lines. Note how the quarry lies on the ridge side opposite of the suburban developments of Clayton. Out of sight, out of mind...
North Peak is about a mile northeast of the main summit, and only about 300 feet shorter. Like the main summit, it is composed primarily of rugged Franciscan chert. Chert develops on the deep ocean floor as myriads of one-celled creatures with silica shells sank to the bottom and became more compacted (diagenetic alteration). The rock was carried on the Pacific Plate for thousands of miles before being scraped off in the subduction zone along the western edge of North America.
 The view to the east and southeast reveals my home. It's flat. They grow lots of stuff there.

Actually though, the oak-covered ridges in the foreground reveal something of interest. The Great Valley is a deep trough with upwards of 25,000 feet of sedimentary layers dating back to the Mesozoic Era, the age of the dinosaurs. We would know little about them except that along the eastern Coast Ranges, the sediments have been curled upwards and exposed by erosion. The rocks surrounding the core of Mount Diablo are in fact called the Great Valley Group, and they contain a rich fossil record, including plesiosaurs, ichthyosaurs, mosasaurs, and even an occasional dinosaur bone.

The easternmost section of the trail offers an excellent exposure of the Franciscan chert called the Devil's Pulpit. No one walking by was able to resist the temptation to climb it, including me!
The southern flank of Mount Diablo was burned last September. With the horrific drought, regrowth of vegetation has been limited, but there were lots of interesting flower species. The views included the Livermore Valley and the South Bay. A short distance later, I reached the end of the trail and we headed down the mountain. We made one more stop, at the very cool sounding Rock City.
After visiting with the resident raccoon, we set out to explore the bizarre rock exposures. We were looking at the Domengine Sandstone, a coastal estuary deposit that included extremely pure quartz sandstone and low grade coal called lignite. Earlier in the day we had explored one of the coal mines at the Black Diamond Mines Regional Preserve.
We made our way through a warren of criss-crossing trails and followed a sandstone ridge to Sentinel Rock. It is an eerie landscape, but it's also a lot of fun to explore.
Knowing that Sentinel Rock would be an irresistible but dangerous climb, the park administration installed cables and carved out steps.

Mt. Diablo State Park is an absolutely fascinating and beautiful island of wilderness in the midst of the Bay Area. It is a great place to visit, and a marvelous geological wonderland. If you are ever in the region, check it out!
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Up Close and Personal with a Western Tanager

May 25, 2014, 1:05 am
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Seasoned birders won't be surprised at the excitement a rank amateur like myself feels the first time he or she sees an interesting bird up close. Western Tanagers (Piranga ludoviciana) are relatively common forest and woodland birds across the western United States and Mexico and I'm sure they are seen often by the experts.  I've only been seriously seeking out new species for the last five months, so I still get to experience the joy of seeing something new and different on a fairly regular basis as I add to the list of observed species.
I've known about Western Tanagers for a long time, but I've never been close enough with an adequate camera to actually get decent photographs of one, but that changed today. We were exploring the upper reaches of the Stanislaus River in the Sierra Nevada of California, and as I was driving down the Clark Fork Road at the end of the day, I saw a flash of yellow out of the corner of my eye. I hit the brakes, hoping against hope that I wouldn't spook the brightly colored male.
He didn't spook. I snapped a few distant shots, and then backed up the car hoping to get closer (I know that sounds like an odd way to do it, but from only forty or so feet away, getting out of the car would have spooked it more, I think). He hung around, as if he was observing me (a large rival in his territory?).
The tanagers are a large and diverse group of passerine birds centered mostly in the American tropics, but the Western Tanager ranges farther north than any other species, as far southern Alaska. For being so brightly colored, they are not often seen, as they tend to hang out in the upper canopy of the forest. I felt privileged to spend a few minutes observing this one, from basically all angles. Was he sending me a message with this last shot?

Brightly colored birds often carry the seeds of their own destruction because their feathers may be in high demand for one reason or another. Looking at the tanager reminded me of the large number of species of Honeycreepers that once existed in the Hawaiian Islands. A few of them are still hanging in there (two out of the original 51 species), but most of the others are extinct or nearly so, in part because Hawaiian royalty centuries ago demanded robes made out of their brightly colored feathers (habitat loss, malaria, and competition with invasive species and predators were major factors as well). The tanagers, with their wide range across all the western states avoided such a fate, but they were for a time considered agricultural pests and were poisoned or shot. They are protected today, and their numbers have grown to where they are a "species of least concern".

It was a privilege to see one up close and personal today.

PS: Mrs. Geotripper took a short video of the same bird...


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The Other California: Highway 108 and Donnell Vista - like Yosemite, only with Volcanoes!

May 25, 2014, 6:29 pm
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Those of you who've followed my blog over the years may remember that I produced a blog series called "The Other California" which existed long before any Toyota commercials with a similar slogan. I come back to it time and again when I find (or rediscover) those places that don't always show up on the tourist postcards, but which have incredible geology and are scenic to boot.

Today we are exploring a few corners of the Upper Stanislaus River drainage in the country north of Yosemite National Park. People from outside the region can be forgiven if they think that the Sierra Nevada is just Yosemite Valley, Sequoia National Park, and Lake Tahoe. The range is 400 miles long, and pretty much all of it is spectacular, except Yosemite and Sequoia are just a little more so. I cannot doubt that if Yosemite Valley didn't exist, the upper Stanislaus would have been one of California's national parks. In some ways, Sonora Pass and the upper Stanislaus are even more interesting in the geologic sense. The reason? Volcanoes.

Donnell Vista Point on Highway 108 about 18 miles above Pinecrest Lake and Strawberry is the site of today's exploration. The parking lot and quarter-mile trail to the viewpoint were recently renovated with funds provided by the America Recovery and Reinvestment Act. The old worn-out trail was resurfaced, and a new ADA compliant trail winds along the western part of the slope, providing some new views to the west.

The first thing one notices from the overlook at Donnell Vista is the deep U-shaped canyon occupied by the lake behind Donnell Reservoir. During the Pleistocene Ice Ages, rivers of ice repeatedly scoured the gorge below, with the last glacial stage ending only about 12,000 years ago. The ice exposed the underlying granite, forming steep cliffs and numerous small rounded asymmetical domes called roches moutonnées. Some nice examples of glacial polish can be found in the region.

The ice in most places removed a cover of volcanic lava flows and any soils were stripped away as well. As a result, wide areas of granitic rock are exposed, and the forest grows only in fractures and joints where bits of soil can accumulate.

Glaciers also scour out basins where lakes can subsequently form, but the lake below the view point is clearly not natural. It is Donnell Reservoir, constructed in 1957 by the Oakdale-South San Joaquin Irrigation district for storage of water for agricultural irrigation and power generation. It stores a bit more than 60,000 acre-feet of water which today is only used to generate electrical power. Storage for irrigation now takes place downstream in the much larger (and more controversial) New Melones Reservoir.

The high peaks to the north and east of Donnell Vista preserve the evidence of the volcanic activity that took place here 10-12 million years ago. The few remnants not stripped away by the ice form the mesa-like peaks on the skyline. When the volcanoes were active, the region would have looked a great deal like the Mt. Lassen volcanic center, which remains active today.

The lava flows filled a fault basin near the present-day Sierra Crest in the vicinity of Sonora Pass, and at times spilled over into the adjacent river valleys. One lava flow traveled nearly sixty miles to Knights Ferry in the Sierra foothills above Oakdale. The landscape surrounding the lava flow eroded away during the uplift of the Sierra Nevada block, leaving the lava flow as a prominent ridge called aninverted stream.
The upper drainage and headwaters of the Stanislaus River up to and over Sonora Pass offers up some fascinating geology. I helped edit a field guide of the geology of the region for a meeting of the National Association of Geoscience Teachers in 2012. It's for sale through Sunbelt Publications and the proceeds support scholarships for geology majors in California, Nevada and Hawaii. Get more information about the book here.

PS: Ron Schott has a great gigapan shot of the view from Donnell Vista at  http://www.gigapan.com/gigapans/114032

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The Other California: Clark Fork of the Stanislaus, a quiet version of Yosemite

May 27, 2014, 8:55 pm
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It's not really fair, of course. No place is like Yosemite, and I shouldn't compare Clark Fork to Yosemite. I doubt there is anywhere in the world that can compare to Yosemite Valley with the high waterfalls, sheer cliffs and strangely shaped domes. But there are some things that are not so nice about Yosemite. It's been used and abused for the last century and a half, and today something like four million people crowd into the few square miles of valley floor. It can be noisy, smoky, and crowded. It's possible to find lonely places on the valley floor where nature still dominates, but it's not easy.
Clark Fork on the Stanislaus River is a world apart from Yosemite Valley. Like Yosemite, it was carved by river erosion, followed by glacial scouring, although not to the same depths. There are small waterfalls and cascades, but nothing like the stunning leaps of Yosemite Falls or the others.
What is there is in Clark Fork is peaceful and uncrowded serenity. A single paved road diverges from Highway 108 and follows the valley for nine miles, passing just a few organizational camps and three campgrounds. No resorts, no stores, and no crowds. We were there on Memorial Day weekend, and there were still campsites available on Saturday evening. The road ends at beautiful Iceberg Meadow, which at this time of year was filled with Water Plantain Buttercups (to the best of my guessing)

Brooding over the meadow is the unique granitic monolith called simply The Iceberg. It's 8,350 feet high. From the perspective of the meadow it looks like a prominent peak, but a look at the topographic shows it to be the last knob of a long divide between Disaster Creek and Clark Fork. Just two miles away, Disaster Peak rises 1,600 feet higher.

The peak is composed of the granodiorite of Topaz Lake, which at about 84 million years is one of the youngest granitic intrusions in the Sierra Nevada batholith (granodiorite is similar in appearance to granite, but contains more plagioclase feldspar and mafic minerals that makes it slightly darker in color). The rock is broken up into joints that are caused by pressure release when the rock is exposed by erosion. This explains the general lack in Clark Fork of bold cliffs like El Capitan or Half Dome, which are relatively less affected by jointing. The rocks of peaks like the Iceberg are more readily eroded by glaciers, which can pluck out the jointed blocks or rock.
Photo by Mrs. Geotripper

Very much unlike Yosemite, there is an abundance of volcanic rocks on the higher ridges above the valley. They are visible from various points along the road and can be accessed by trails that lead up Clark Fork and side canyons like Arnot and Disaster Creeks. Similar volcanics are found along Highway 108 near the summit of Sonora Pass. As noted in the previous post, these rocks were erupted between 10 and 12 million years from a volcanic center along the Sierra crest, similar in appearance to the Mt. Lassen volcanic complex further to the north.
We didn't have a lot of time on our visit last Saturday, but we walked around Iceberg Meadow and saw not a single other person. Cattle are still allowed to graze in the region, but the meadow itself is fenced off to preserve it from damage (deer have no problems jumping the fences). Despite the drought, the meadow is a bright emerald green in places, though in some parts it looked bluish from the impending bloom of some irises or other swamp flowers. It's only May, and it should be still partly covered in snowbanks, but we'll take the short spring over none at all. I hope the drought breaks this year...
Photo by Mrs. Geotripper

Clark Fork is a wonderful part of the Sierra Nevada, one of those largely ignored corners of a beautiful mountain that would probably be a national park in any other setting. It is the kind of place that John Muir wrote about in the Mountains of California when he said “Climb the mountains and get their good tidings. Nature's peace will flow into you as sunshine flows into trees. The winds will blow their own freshness into you, and the storms their energy, while cares will drop away from you like the leaves of Autumn.”

Photo by Mrs. Geotripper

This is one of the irregular entries in my blog series called "The Other California" which existed long before any Toyota commercials with a similar slogan. It is an exploration those places in my fair state that don't always show up on the tourist postcards, but which have incredible geology and are scenic to boot.
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Spring colors from Clark Fork of the Stanislaus River (in the Other California)

May 28, 2014, 11:16 am
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Pride of the Mountain (Penstomen newberryi)

Today's post is a brief collection of the spring wildflowers we saw while we explored Donnell Vista and Clark Fork of the Stanislaus River over Memorial Day weekend. As many of you know well, I'm no botanist, so I freely accept corrections to my identification of particular flower species. I spend weeks in my mineralogy labs trying to get my students to identify their lab specimens by keying them out, but they'll often go right to the book and compare their sample with pictures. So how do I identify wildflowers? Keying them out? Of course not! I go to a wildflower book and flip pages until I find a similar picture....

I've been seeing the bright pink Penstomen species Pride of the Mountain growing in granite roadcuts for years without sitting down and identifying the species (top picture). They must be pretty extraordinary because alpine granite soils must be one of the least fertile growth environments in existence. There isn't much clay to store nutrients, the growing season is very short, and the water can't persist all that long in the small granite crevices, and yet these flowers seem to explode out of the barren rock.
Pussypaws (Calyptridium umbellatum)

Pussypaws are another extraordinary survivor, growing in barren stretches of sandy granitic soil where little else can grow.
Pussypaws (Calyptridium umbellatum)

The flowers are small and the colors muted from a distance, but this trip I got down on my belly and took a closer look. From this perspective, the flowers reveal a world of color and intricate patterns.
Pussypaws (Calyptridium umbellatum)

Spreading Phlox was another flower growing in the harsh environment of granitic soils (which, by the way, is called grus).
Spreading Phlox (Phlox divaricata)

In the deep forests along Clark Fork we saw a lot of Snow Plants (Sarcodes sanguinea). These are strange organisms that have no chlorophyll and must depend on fungus in their root system to make available the nutrients they survive on. They survive off of organic material in the forest soils.
Snow Plants (Sarcodes sanguinea)

Snow Plant (Sarcodes sanguinea)

Iceberg Meadow was covered with what I think were Water Plantain Buttercups (Ranunculus alismifolius).
Water Plantain Buttercup (Ranunculus alismifolius)

And finally, we found what I think is Pacific Hound's Tongue (Cynoglossum grande) growing at the margin of Iceberg Meadow. The flowers were small, but the blue color was striking.  
Pacific Hound's Tongue (Cynoglossum grande). Photo by Mrs. Geotripper
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Headed for the Hinterlands: Basin and Range and the Colorado Plateau.

May 29, 2014, 10:12 pm
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Hitting the road tomorrow, and much looking forward to getting away for a few days. It may seem like I do a lot of traveling, and I have been, but it's mostly been day trips. We're putting in a few miles this time, heading across the Basin and Range province to an exploration of the Colorado Plateau.
If I can, I'll put in a few dispatches from the road. We'll hopefully be busy doing geology, and discovering some new vistas. I found out that my friends from SBCC will be at Grand Canyon the same time as I will, so I hope to see some familiar faces out there!

In the meantime...
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"Fly-over Country" Moniker Doesn't Do this Land Justice: Crossing the Basin and Range

June 1, 2014, 12:20 am
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The Basin and Range province is one of the largest geological provinces in North America, covering all of Nevada, parts of eastern California, half of Utah, and large parts of Arizona. It is also one of the least populated, at least outside of the urban centers of Las Vegas, Phoenix, Reno, and Salt Lake City. The region was stretched in late Cenozoic time (during the last 30 million years) so that the crust broke apart and gigantic blocks slipped against each other like shelves of books tipping over. Several hundred horsts (ranges) and grabens (fault valleys) are the defining features of the province.

We were on our way to an exploration of the Colorado Plateau, but needed to make our way to Las Vegas to meet our group. We could have taken the freeways through the Central Valley and Mojave Desert, but I've been down that road several hundred times over the last quarter century. We elected to cross the Sierra Nevada at Tioga Pass and cross the high ranges and deep basins of the region referred to by many as "fly-over" country. It's barren on some ways, but it is a treasure in so many others. How many places will you visit in your life where you have a decent chance of being the only human being on a particular mountain range? That can happen out here.
I could be accused of false advertising in showing these pictures of the alpine scenery of Yosemite National Park, but the presence of the Sierra Nevada is what forms the character of the Basin and Range. Many consider the Sierra to be the westernmost of the Basin and Range mountains, and the high 400 mile long mountain crest blocks the majority of precipitation from ever reaching the region. During the ice ages, the glaciers of the Sierra had a profound effect on the province, primarily in the formation of vast freshwater lakes in some of the driest places on the planet, Death Valley being an outstanding example. It once contained a lake 100-plus miles long and 600 feet deep.

A few of the lakes persist, barely. After we crossed Tioga Pass, we had an outstanding view of Mono Lake, which is huge, but it was once much larger and deeper. Evaporation (and water diversions by Los Angeles) have left behind saline water in which only small fairy shrimp and brine flies can survive. Not a complex ecosystem, but millions of birds depend on the rich protein.
Those birds include species like the gull below, which I suspect of supplementing its diet with scraps of sandwiches from the Whoa Nellie Deli!

The White Mountains, the next major range east of the Sierra Nevada, are spectacular, with a high point of 14,252 feet at White Mountain Peak, and several others exceeding 13,000 feet. The north end of the range extends into Nevada where Boundary Peak forms the highest point in the state of Nevada at 13,147 feet. We headed south along the east flank of the mountains in Fish Springs Valley.
The valley supports some ranching and alfalfa fields, but it's also very dry. We saw some immense dust devils that looked a bit like tornadoes.
We climbed to Lida Summit and looked back across one mountain range after another to the Palisades Crest in the Sierra Nevada.
A number of wildflowers were in evidence, including many Prickly Poppies and Globe Mallows. It's dry country, but lots of plants have adapted to the harsh conditions. The extreme range of elevations from 14,000 feet to below sea level have caused the province to have a stunning number of plant species.
We headed down from Lida Summit and started south towards Las Vegas on Highway 95.
As we rolled slowly (lots of speed traps) through the town of Beatty, Nevada, we encountered dozens of wild Burros. They are the descendants of animals abandoned by the early miners, and they have become a pest in many ways, contributing to overgrazing, trampling rare plants, and fouling springs, but darn it, they're also terribly cute. In hopes of controlling the populations of these creatures the Bureau of Land Management captures as many as they can and puts them up for adoption.

We made to Sin City, and today we met our fellow travelers for the coming week. We had a great day touring the geological environs of Las Vegas, and pictures will undoubtedly appear soon here on Geotripper!
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Revealing the Riddle of the Red Rocks

June 2, 2014, 11:05 pm
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 It's pretty amazing the places that didn't get made into national parks. It's pretty amazing that tens of millions of people visit Las Vegas and never make it just a few miles west of the city limits to see an incredible place where the rocks are red, and the rocks are a bit of a riddle. The problem? The rocks on the top, the gray limestone seen on the distant ridges is 300 million years older than the red rocks underneath. They are out of proper order.
The red rocks are the Aztec Sandstone, a Jurassic aged sand dune deposit that is correlated with the Navajo Sandstone, found in national parks like Zion, Arches and Capitol Reef. They developed in an immense sand dune "sea" that once extended from Wyoming to Arizona to eastern California.
The red color comes from iron oxide (the mineral hematite, or natural rust) coating the sand grains. I haven't found a lot of agreement over whether the red staining is a secondary effect, or a primary feature of the sandstone.
In either case, the outcrops are colorful, in shades of white, pink, red and brown. The rock exposures also display beautiful crossbedding, the sloping layers representing the slip faces of the ancient dunes, frozen in time by calcite or other mineral cement. In many places the rocks are broken up as if they have been through a gigantic nutcracker.

Which, by the way, they have.
Faults run through the region, an earlier set representing intense compression related subduction off the western coast of North America, and a later set formed during the extension that led to the development of the Basin and Range Province. The compressional thrust faults had the effect of pushing the older limestone rocks up and over the younger Jurassic sandstone during the Sevier Orogeny towards the end of the Mesozoic Era (that's the one with the dinosaurs). There are several such faults in the area, but the best known is the Keystone Thrust.
The later normal faulting dropped the valley floors and lifted the mountains, exposing the older faults to view. Erosion has resulted in the spectacular outcrops that make up the conservation area we see today.

Red Rock Canyon National Conservation Area is a wonderful place to visit, whether you've blown all your money at the casinos and can't afford to do anything else (hold back $10 for park admission!), or if you came to Vegas for the expressed purpose of visiting this wonderland of rocks. It is a much better use of your time if you ask me!

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It's a Dam Big Reservoir, But There Are Some Dam Scary Things About It.

June 4, 2014, 10:00 pm
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First off, I am so sorry for the dam puns. I'm a geologist, and we geologists are just no dam good at resisting stupid puns. It's something you'll just have to take for granite.

In any case, this is a dam big reservoir. It's Hoover Dam, the first of the gigantic mega-dams constructed in the U.S. back in the 1930s during the height of the Great Depression. Thousands of hungry unemployed men came from all over the country to work in the construction, and in the dangerous conditions, more than one hundred of them died. It's 726 feet high, which at the time was the highest dam in the world (it's the 18th highest now). It holds back about 30 million acre-feet of Colorado River water, equivalent to more than two years of normal stream-flow. At least, what was normal thirty years ago.
It's an astonishing achievement even if I seem to belittle it with semi-sarcastic puns. Walking across the dam is an experience in perspective. It is really big. Ultimately, some thirty million people in three states and Mexico depend on the water that it stores.
Not that it's pretentious or anything, but there are trimmings that make me think of the old USSR. Gigantic statures of winged gods greet the visitor on the Nevada side of the dam, and a loudspeaker emits a constant stream of platitudes about the glory of the achievement of making a river slow down for an instant of geologic time.
Can you guess the purpose of this golden door? Is it the entrance to the Watermaster's Throne Room, the portal into the Cathedral of Power Generation? No, it's actually the door to the men's bathroom on the top of the dam. Unfortunately it is undergoing renovation, so I can't show you the pretentiousness that awaits within (plus, I would have been arrested as some sort of creepy person).

Still, there are some dam frightening things about visiting Lake Mead and Hoover Dam. First and foremost, the dam is missing something. Water. It's missing a lot of water. It's sitting at the lowest level ever seen since the dam's floodgates closed in the 1930s. It hasn't been full as far as I know since the flooding in 1983, and prospects are not good for changing this situation in the face of ongoing drought and climate change.
Then you see stuff. Walking down the stairway from the new parking structure, there are all these square pieces of metal stuck to the cliff. What the hell? Those are rock bolts, essentially long screws encased in concrete and bolted to the rock wall for the purpose of maintaining the rock wall as an actual wall, instead of a rock fall. If the dam is built in stable rock, what do they need rock bolts for?
Then you start to notice other things. In the roadcuts across the highway from the dam there are strange looking scratch marks on the rock surface. They're called slickensides, and they develop as one block of rock grinds against another. Along a fault. Yeah, those things that cause/result from earthquakes.

Before I started researching the field seminar that I'm currently conducting, I assumed that Hoover Dam was anchored in ancient stable metamorphic and plutonic rocks. That is the kind of rock that is exposed in Black Canyon downstream from the dam. A close look at the rocks reveals a different composition: they are rhyolitic volcanic rocks, and according to the guides and the maps, they are Neogene in age, from around maybe 15 million years ago.
The volcanic rocks erupted in a complicated geologic environment of extension and transcurrent faulting that opened up spaces between crustal blocks that allowed magma to rise to the surface. They have been complexly faulted, and it turns out that a walking tour of the dam site is a nice lesson in a comparison of normal and strike-slip faulting. The dam engineers and the dam architects back in the 1930s declared the dam abutments to be safe and stable, and who am I to argue with them? I am not a dam engineer or a dam architect. It doesn't look like any leaks are occurring in the canyon walls downstream, unlike a certain other dam reservoir that I was looking at today.
The other dam thing I saw today wasn't really scary, except in my imagination. You have to realize I was looking down 200 feet at this big fish, a carp or something. It may have been three or four feet long, and for a moment it looked a dam shark! Maybe that Sharknado thing really happened, and a few landed in Lake Mead...

The dam morning was almost over, so we hit the road. We were headed towards the Grand Canyon, a much better place to appreciate the Colorado River.
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Exploring the Depths of the Grand Canyon...By Car?

June 8, 2014, 2:13 pm
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The Grand Canyon is one of the great spectacles of the Earth. Millions of people every year stand on the edge of the abyss and peer in, taking in the vivid colors and hidden depths. Tens of thousands venture down some of the few trails that reach into the incredible gorge, and several thousand raft the river. But how many drive the canyon? Did you even know you could?
And no, I'm not talking about visiting the canyon "Thelma and Louise" style...

For more than two hundred river miles, no road crosses the Grand Canyon (plus another hundred miles to Lake Mead). Navajo Bridge near Lee's Ferry is at one end, and Pat Tilman Bridge near Lake Mead is at the other. In between in the depths of Grand Canyon there is a single road that reaches the river. It's called Diamond Creek Road, and it starts on Hualapai Nation lands at Peach Springs. It's a marvelous adventure.

Without even considering the philosophical objections to building roads through the wilderness world of the Grand Canyon (objections I completely agree with), there are staggering engineering barriers. There are a series of formations, including the Redwall Limestone and the Coconino Sandstone that form sheer cliffs. The locations of trails in the Grand Canyon are controlled almost entirely by the few locations where they can surmount the cliffs of these two layers.

At Diamond Creek, the Hurricane Fault has offset the formations in just such a way that the cliffs can be avoided entirely. For the entire twenty mile length of the road, there is nary a cliff to worry about, as the road follows the bottoms of desert arroyos and washes. The biggest worry is flash floods and mudflows, which can easily shut down the road in July and August during the monsoons (and badly inconvenience river rafters who plan to take out at Diamond Creek).
One can certainly discuss the idea that it's "cheating" to drive to the bottom of the canyon, and there is a certain validity that scenery that hasn't been "earned" by completing a stiff hike might end up being less appreciated. But many people can't handle the very strenuous hiking and many simply don't have the time. Driving down into the canyon is a unique opportunity to study the oldest rocks of the canyon, the ones that are the very hardest to access in any other situation.
Diamond Creek cuts through to the Granite Gorge Metamorphic Suite, which is the oldest group of rocks found in the American Southwest, dating to as early as 1.8 billion years ago. At roadside there are marvelous exposures of schist, gneiss, and pegmatite granite with bright shiny crystals of muscovite mica and quartz.
A bit farther up the canyon one can see the layers of the Tonto Group, a series of three formations called the Tapeats Sandstone, the Bright Angel Shale, and the Muav Limestone. The three layers formed as the Pacific Ocean transgressed and covered much of the western North American continent in Cambrian time, just over 500 million years ago. The Tapeats Sandstone sits atop the rocks of the Granite Gorge Metamorphic Suite.

That last sentence needs a bit more explanation. The boundary between the Tapeats and the Granite Gorge rocks is a profound unconformity representing a gap of more than a billion years. This unconformity is actually called the "Great Unconformity", and is an erosional surface that was witness to not one, but two major mountain-building events. The metamorphic rocks were once the core of a vast mountain range that formed 1.7 billion years ago when the North American continent collided with a set of two exotic terranes, the Yavapai block and the Mazatzal block. Imagine an island the size of California or New Zealand grinding into the edge of a continent along a subduction zone and you will get the picture. This massive mountain range eroded to a flat low-relief surface over the next few hundred million years.
Later on, about a billion years ago, the continent stretched and broke apart, forming a series of fault-block mountain ranges that reached heights similar to the mountains in and around Death Valley National Park today. The rocks of these mountains are exposed in the easternmost part of the Grand Canyon, but they too were eventually eroded down to a low-relief surface as well, although small  ridges a few hundred feet high persisted. Along the lower reaches of Diamond Creek Road, you can lay your hand on a boundary between two rock sequences with a gap of more than a billion years between them. The unconformity can be seen in the photo above where a conglomerate rests on contorted metamorphic rocks in the bit of shadowed ledge. The "Diamond" of Diamond Creek is the uniquely shaped peak on the left side of the photograph. It is actually a sliver of rock caught between two branches of the Hurricane fault system.
Another layer that is prominently exposed along Diamond Creek Road is Devonian-aged Temple Butte Limestone. Most park visitors never see it because in the eastern section of Grand Canyon National Park the Temple Butte is a discontinuous thin layer that is pretty well invisible from the rim. In western Grand Canyon it is more than 700 feet thick. It formed as a tidal estuary and tidal flats along the edge of the continent about 385 million years ago.
The most "mysterious" aspect of Diamond Creek and Peach Springs Canyon is that the tributary canyons to this creek are older than the Grand Canyon itself. It's an odd problem. Along the upper reaches of Peach Springs Canyon, there are a series of Paleocene to Miocene-aged rocks clinging to the canyon walls. They once filled the canyon, meaning the canyon was carved prior to sixty million years ago, and the rivers that carved it flowed northeast, opposite of the Colorado River today. Apparently the land subsided so that the canyons were filled with sediment, and then they were exhumed when the modern Grand Canyon was carved, most likely within the last four or five million years.
Photo by Mrs. Geotripper

Diamond Creek is a fascinating excursion. It is entirely on Hualapai lands, and they charge a fee of around $25 per person for permission to drive the road. I never mind paying the fee, because the tribe doesn't have many sources of income or all that many jobs on the reservation. The town of Peach Springs where the road starts has a very nice motel and restaurant (and not much else), and if you are a train lover, you'll be able to listen to them all night long. The rails are amongst the busiest you'll ever see.The town is on one of the last remaining stretches of the original Route 66.
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