Happy Holidays from the Geotripper Gang.

Merry Christmas and Happy Holidays to all from the gang at Geotripper (that would be me and Mrs. Geotripper, and two cats)! As is our tradition, we offer up once again a very big Christmas tree, the General Grant Tree in Kings Canyon National Park. The tree is so large (268 feet high, 40 feet across at the base) that it took three pictures for me to capture it.

The tree was declared by Calvin Coolidge in 1926 to be the nation's Christmas Tree. At an early ceremony, park superintendent Colonel John White said ""We are gathered here around a tree that is worthy of representing the spirit of America on Christmas Day. That spirit is best expressed in the plain things of life, the love of the family circle, the simple life of the out-of-doors. The tree is a pillar that is a testimony that things of the spirit transcend those of the flesh."

I don't have a shot of the General Grant all dressed in snow, so here is another Sequoia after a surprise storm during an April trip some years ago.

Upper Yosemite Falls with a rainbow

The Sierra Nevada, as exemplified by Kings Canyon and Yosemite Valley, is the kind of place we think of when we dream of a white Christmas. We try to get up there whenever we can at this time of year.

The Cathedral Rocks

Christmas season is a time of gifts, and year by year I think more of the gifts that come from somewhere besides a store. One of the most precious gifts in my life is that I am able to live near places like these, and that I have the health and ability to visit them often. In places like Kings Canyon and Yosemite, we have a precious gift of nature. There are places near you that are gifts as well. It might be another national park, or it could be a state park. It could simply be a river, or a spot of forest surrounded by a city. My wish for you is that you can discover and explore a new place in the coming year. And if it is threatened, I wish that you will have the resources to help protect it. I have a feeling that we will need to fight for many of our precious wild places in the coming years.

El Capitan

I want to thank all of my readers, new and old, for your attention and kind comments over the last ten years that I've been blogging (that's 1,970 posts now, not that anyone is counting). I've always enjoyed hearing from you, and appreciate getting to know new friends from all over the world. I wish a wondrous season to you all!

Although this is a repeat of my traditional Christmas message, I can't help but add a bit the beauty I've experienced this evening, my first white Christmas in many, many years. The snow began here in the Seattle region in the afternoon, and now late in the evening there are a few inches on the ground. I had to relearn my snow-driving skills in a hurry. My friends in snow country might not understand the thrill, but my California friends who never see the stuff up close will understand completely. Have a wonderful holiday season!

Bug Art at Beetle Rock

There is always something new to see when you are on the road. We were exploring the geology of Sequoia National Park for a field class this last weekend, and we saw many marvelous and beautiful things, but this was a new one for me.

We were at Beetle Rock, an exfoliation dome in the Giant Forest area of the park. The view was wonderful, but I noticed the oak trees at the edge of the clearing seemed "off". There was a mixture of green and brown in the foliage, and it wasn't fall colors. A closer look revealed feeding trails of some kind of insect, perhaps some sort of Leaf Miner (I would appreciate some help with identification, bug people!).

I don't know if this extensive pattern of feeding is detrimental to the health of the tree. There are a lot of changes happening in the Southern Sierra Nevada as a result of extended drought and climate change, and the number of dead conifer trees was truly depressing. I'm worried that something has also made the oaks susceptible to insect attack.

I've not noticed this sort of thing in the past, but then again, I've been known to not pay close attention to plants when there are rocks to look at. And the rock at Beetle Rock is pretty interesting. I just wasn't expecting actual beetles...

The Sequoia Underground: An Exploration of Crystal Cave

It's true that Crystal Cave in Sequoia National Park can hardly be described as a wild cave. Since its discovery in 1918 and its development as a park attraction in 1940, the cave has been visited by more than a million people. Dynamite was used by workers to widen passageways, and besides the lighting and pathways, there was a generator, and underground bathrooms. And yet there is still something wild about the cavern. Because it was discovered by park personnel and protected from vandalism from the beginning, the cave presents some wonderful examples of speleothems (cave decorations). The cave has a total of 2.42 miles of passageways (the third largest in California), but only a fraction ever receives visitors. The rest remains an underground wilderness.

The cave is an integral part of our field studies course on the geology of Sequoia and Kings Canyon National Parks. We paid a visit this last weekend and made the cave our first stop. Our tour began with an orientation on White-nose Syndrome (a fungus that kills bats), and sterilized our shoes. We then started down the half mile trail to the cave entrance.

The trail itself is a pleasure, and a good introduction to the local geology. The rocks are part of the Kings Terrane, a group of metamorphic rocks that formed in a shallow marine setting in Triassic and Jurassic time (around 200-150 million years ago) with some parts possibly older. The rocks formed in the Pacific Ocean and were accreted to the western edge of the North American continent as the mass of continental crust entered into the vast subduction zone that was consuming the ocean crust. The collision and subsequent invasion of the rock by molten granite caused the silt, sand and lime mud to become schist, quartzite and marble. It is in the marble that we find the caverns forming.

The trail provides a nice view of the marble cliffs. Permanent springs cause Cascade Creek to flow year round, providing a cool stretch of trail on a hot day and some beautiful small waterfalls.

Soon we reached the entrance to the cave and met our guide. The cave is administered by the Sequoia Natural History Association and is generally open for tours from the early spring to late fall.

A cool breeze was blowing out of the cave. The temperature is controlled by the average year-round climate, so the cave is relatively cooler in summer, and warmer in winter. Although the darkness of the cave provides little in the way of food, a number of animals do live in the cave, including a number of species of bat, and small arthropods like spiders, isopods and pseudoscorpions.

Entry into the cave is controlled by the famous spider-web gateway. I remember vividly seeing that gate when I visited the park for the first time as a child in the 1960s, and I remember the gate (and the underground bathrooms) the best.

Given the number of visitors, it's amazing that any cave decorations are left. It's to the credit of the park service and history association workers that so little damage has been done, although plenty of bad things have happened (the park service actually allowed self-guided tours for a brief time with disastrous results). The improvements to the pathway have actually meant that some of the stalactites and stalagmites have begun healing from previous damage, as evidenced by the pure white calcite on some surfaces. Dust from tramping feet and smoke from torches left many features a dingy yellow or brown color.

We passed some beautiful stalagmites on the floor of the cave, and then moved into the Junction Room, which was filled with the sound of babbling little brook. The cave is still very active, as it diverts a nearby creek underground. There are several levels to the cave, developed as the local canyons outside have gotten deeper, causing the rivers inside the cave to erode downward. There are numerous benches and terraces attesting to the former presence of higher level streams.

We moved through the Curtain Room, where a profusion of cave curtains and draperies hang from the walls and ceiling of the cave. They are out of reach of vandals and are thus largely unbroken.

The Dome Room contains one of the cavern's most famous features, the Fairy Pools. The rimstone pools and soda straws are actively forming (and recovering slowly from vandalism).

A zoom onto the soda straws (below) shows the water droplets on the ends. In these conditions, soda straws can grow at maybe an inch per century.

The unbroken draperies show an intricate structure.

The Marble Room is the largest in the cave, extending for more than 100 feet, with the ceiling 30 feet above. It is an amazing sight. It's also where they turn out the lights and let explorers get a feel for total darkness. Some people really don't like the sensation.

There are nearly 300 known caverns in Sequoia and Kings Canyon National Parks (Boyden Cave, another developed cave, is just outside the park boundary). The caverns include Lilburn Cave, which at 28 miles of passageways is in the top twenty of the largest caves in the nation. Most of the wild caves are remote, and their locations are kept secret for obvious reasons. Clough Cave was known a century ago as a beautiful cave festooned with thousands of stalactites. When the cave was publicized, the speleothems started to disappear, and today Clough Cave is pretty much a featureless hole in the ground. Several vandals were caught by park rangers in 1997 stealing some of the last artifacts in the cave. What a crying shame.

In the meantime, if you ever visit Sequoia or Kings Canyon, be sure to give the cavern a look. You won't regret it!

The Hazards of Field Work: Distraction by Cuteness

Okay, maybe this one wasn't cute...

The perils of teaching in the field are paramount and legion: attacks by killer bees, mosquito bites, falling off cliffs, sunburn, and multitudes of other hazards. But there is something visceral with coming face to face with an animal that is capable of killing you with a swat of its claw. But it wasn't likely to be one of these fine creatures. According to my sources, there hasn't been a fatality in California from a Black Bear attack in at least a century. These animals, as powerful as they are, are incredibly patient with human beings.

I've seen a handful of bears over the years in my travels, but this last weekend in Sequoia National Park was extraordinary. I was teaching a field class on the geology of Sequoia and Kings Canyon National Parks when we saw not one or two, but seven different bears. Despite their reputation (which is mostly unearned), the bears were docile, doing bear things instead of ripping into cars or attacking humans. For all my travels, I've never seen a bear cub in the wild, but this last weekend I saw four of them!

The first ones interrupted my introduction to the geography of the Sierra Nevada. We had just arrived at Crescent Meadow in Sequoia when one of the students spied a bear through the trees. After a few moments we realized there were two of them! The two cubs were hunting for food in the meadow and occasionally playing with each other in a rough and tumble wrestling match.

Photo by Mrs. Geotripper

After finishing at Crescent Meadows and climbing Moro Rock we drove to the Giant Forest and prepared to walk down and see the General Sherman Sequoia tree, the world's largest living thing. We found these adorable cubs instead, looking for grubs or seeds in the forest next to the parking lot. Far from feeling threatened, we wanted to just pick them up and cuddle them. Which of course would have been stunningly stupid. We got out the cameras instead and watched them for a while.

They were doing the right thing, snuffling in the forest instead of tearing into cars. They seemed pretty unconcerned about the gathering crowd of people. In case you are wondering, we did know where momma bear was; she was up in the top of the adjacent tree knocking branches to the ground.

The cubs knew momma was up there, but didn't seem overly anxious to be climbing the tree. The crowd of humans grew a bit, but the cubs seemed unfazed by it all.

Momma finally climbed down out of the tree and collected up her young ones. I was pleased to see their total disinterest in the nearby cars. After a few more moments she wandered down the hill and the cubs followed. I was mesmerized by the sight. We gathered up the camera equipment and headed  down into Kings Canyon, our stopping place for the night.

It may not have been particularly geological, but it was a fun distraction!

A Merry Christmas and Happy Holidays to All!

Merry Christmas and Happy Holidays to all! To celebrate, I offer up once again a very big Christmas tree, the General Grant Tree in Kings Canyon National Park. The tree is so large (268 feet high, 40 feet across at the base) that it took three pictures for me to capture it. The Giant Sequoia trees have an ancient lineage that extends back to the era of the dinosaurs. They once grew across the northern hemisphere, but climate change and ice ages conspired to eliminate them from their former range except for a few dozen groves in the western Sierra Nevada. They can live for several thousand years, and few things can kill them, their main enemies being crown fires (ground fires don't hurt them generally) and the lumberman's saw.

The General Grant tree was declared by Calvin Coolidge in 1926 to be the nation's Christmas Tree. At an early ceremony, park superintendent Colonel John White said ""We are gathered here around a tree that is worthy of representing the spirit of America on Christmas Day. That spirit is best expressed in the plain things of life, the love of the family circle, the simple life of the out-of-doors. The tree is a pillar that is a testimony that things of the spirit transcend those of the flesh."

I hope that you all have a wonderful and safe holiday.

Oh, if you think Christmas trees should be decorated, I don't have one of the Grant Tree all dressed up for the holiday, but here is a nicely flocked Sequoia tree from a different trip...

The Other California: The Biggest Living Things and the Deepest Canyon in the U.S. (maybe, almost, perhaps)

Sequoia and Kings Canyon National Parks were established 50 years apart (1890 and 1940), and they preserve different aspects of the Sierra Nevada, but they are adjacent and as such are jointly administered by the Park Service. My Other California blog series is an attempt to spotlight the lesser known parts of our state that don't always show up on the postcards that tourists buy, but which have incredible geological features. As a pair of national parks, Sequoia and Kings Canyon don't seem to fit the bill, but I include them because the two parks are less visited, and yet have some of the most spectacular geological scenery to be seen anywhere. How many places can boast the highest peaks, the deepest canyons and the biggest living things in the world?

A bit of perspective on my claims, though. Sequoia National Park includes the highest peak in the lower 48 states, with Mt. Whitney (14,505 feet; 4,421 meters). Denali in Alaska is much higher, and Mauna Kea and Mauna Loa on the Big Island of Hawaii are the tallest mountains in the world (if you measure from the seafloor). Kings Canyon has a reasonably valid claim to being the deepest canyon in North America, but the deepest part of the canyon lies a few miles downstream of the park boundary (though it is partly protected as Giant Sequoia National Monument). But the biggest living things? Absolutely.

There has always been a bit of confusion about the Giant Sequoias (Sequoiadendron gigantea), because California has two gigantic tree species. The other is the Coast Redwood (Sequoia sempervirens), which grows in a narrow coastal corridor between Big Sur and the Oregon state line. The Coast Redwood grows to immense heights (nearly 400 feet), but is usually slimmer. The tallest Sequoia trees usually don't exceed 300 feet (the tallest is 311 feet), but the trunk is more robust to a high level, so the shorter trees have the greater bulk, making them the largest living thing on the planet. The state legislature was confused certainly, as they made the "native redwood" into the state tree without realizing the two trees were distinct. The attorney general of the state eventually got involved, making a final ruling declaring both species to be the state tree. Both tree species live for thousands of years, but neither is the oldest living thing in existence. That honor goes to the 5,000 year old Bristlecone Pine, also a California resident species.

The trees are tremendous. They occur in about 60 groves between about 4,600 and 7,000 feet along the western slope of the Sierra Nevada. Such giant trees would seem irresistible to loggers, and many were cut, but the wood was actually of low quality for most purposes and was usually made into pencils, shingles or grapevine stakes. Today nearly all the groves are protected in the national parks (Yosemite, Sequoia, and Kings Canyon), a national monument (Giant Sequoia), and a state park (Calaveras Big Trees).

The trees have a geological story. They once thrived across the northern hemisphere, and in North America fossils of the trees are preserved in Yellowstone and Petrified Forest National Parks (the direct ancestors are preserved in Nevada). The petrified trees in Yellowstone are several tens of millions of years old, but the trees in Petrified Forest are several hundred million years old! Ancestors to the Sequoia date at least to the Jurassic Period, so the trees were witness to the evolution of the dinosaurs and their extinction. Climate change seems to have been the tree's nemesis, and the Pleistocene ice ages probably eliminated them from most of their former range. The trees were able to survive in the Sierra Nevada in part because they could propagate downslope and upslope in response to the advancing and receding glaciers (see this National Park Service article for the details on the origin and distribution of the Sequoia trees).

I'm opening a can of worms by discussing the deepest canyon in North America. Hells Canyon on the Snake River along the Idaho-Oregon border is usually described as the deepest, but measurements vary, as well as the precise definition of canyon. I won't make a judgement other than to say that the two canyons are very close to being the deepest, only a few tens of feet apart, and that both of them are 2,000-3,000 feet deeper than the Grand Canyon (The Grand really is grand, though. According to the park service, with a volume of 4.17 trillion cubic meters, it is the largest canyon in the world). Spanish Peak, at just over 10,000 feet (in the photo below), looms 8,000 feet over the canyon bottom at Rough Creek.

How can this canyon be so deep? If you saw my last post, you would recall that the southern Sierra Nevada is topographically different than the northern Sierra. It is more a high plateau than a westward tilting block. The adjacent Central Valley is different as well. It's been sinking, so much so that some of the sedimentary fill has buried portions of the Sierra foothills. Strange things are happening in the southern Sierra, and it may be related to a process called delamination. The Sierra may have had a dense root of mantle material that was out of equilibrium with the surrounding hotter and slightly fluid mantle. The large mass broke away and sank deeper into the mantle. The overlying crustal rock, the Sierra, popped upwards like a ship losing an anchor. The Kings River, with an increased gradient, started cutting rapidly downwards within the last few million years. Spanish Mountain can be thought of a high secondary ridge like the Great Western Divide, but it was breached by the erosion of the Kings River.

What's ironic? The river that carved the deepest (or second deepest) canyon in North America doesn't flow into the sea. The Kings River historically flowed mostly into a large lake in the southern Central Valley (Tulare Lake) and evaporated away. Some distributary channels delivered water to the San Joaquin River (and then onto the Pacific Ocean), but today the river is fully utilized for irrigation, and even the lake is gone, replaced by agricultural fields.

When we visited a few weeks ago, the road into Kings Canyon was still closed. The problem isn't snow (there wasn't any to speak of). The canyon slopes are so steep and rocky that rockfalls are a continuing hazard when the ground is still saturated and subject to freezing conditions. We had to take a pass this time around, but we'll be back in the fall for a field studies class. Look for pictures around early October!

Oh, and there were some cute dogs hanging out at Grant Grove....

The Other California: Springtime along the Great Western Divide

Lupines along the Kaweah River gorge (Moro Rock and Alta Peak in the distance)

The Great Western Divide? Where's that?

My off and on blog series on the Other California is an exploration of the little-known places in my fair state with interesting, even fascinating geological features. Sequoia National Park might seem too familiar a place to be included as part of the "Other California", given that my own definition of the series is that it should include those places that don't normally show up on postcards, and Sequoia National Park certainly does.

So why include Sequoia? The primary reason is that it actually is less known than other parts of the Sierra Nevada. Ask folks where they go in the Sierra, and Yosemite Valley or Lake Tahoe are often the first places mentioned. And people often come to the park not so much for the geology, but for the biology, mainly to see the trees after which the park is named. But the park has a rich geological heritage as well.

Moro Rock from the Kaweah River gorge

The shape of the Sierra Nevada is often described as a tilted block of granitic rock and metamorphic rocks. That's true in the Sierra Nevada north of Sequoia. Driving to Yosemite National Park from the west involves a gradual climb up the western slope that continues to the Sierra Crest before dropping precipitously into the Owens Valley or Mono Lake on the east. Sequoia and the Southern Sierra Nevada is quite different. When one arrives from the west (which actually is the only way in which the park can be approached by roads), the road climbs steeply to a plateau, and the slope continues to a high crest. But not of the Sierra Nevada. It's an entirely separate mountain ridge called the Great Western Divide. The actual crest of the Sierra Nevada lies farther east, across the deep gorge of the Big Arroyo and the Kern River.

The Great Western Divide is a spectacular mountain range. It rises nearly to the height of the actual Sierra Crest, with several peaks exceeding 12,000 feet in elevation (A dozen or so peaks on the Sierra Crest reach 14,000 feet). Despite being far to the south, the peaks were high enough to be scoured by the glaciers of the Pleistocene Ice Ages.

A few weeks back we had the chance to pay an early springtime visit to Sequoia National Park. We came in from the west, up Highway 198 along the Kaweah River through the town of Three Rivers, and then up the Generals Highway to the Sequoia groves for which the park is justly famous. The road is notably curvy, and climbs through a rugged canyon choked with giant boulders that have tumbled from the cliffs above.

We soon passed one of those kitschy things that Civilian Conservation Corps workers in the 1930s seemed especially fond of constructing: a drive-through rock (to go along with "drive-through" trees). They enlarged the opening under the immense boulder, and put the road through it.

If one wonders why the road today circumvents the rock tunnel, one need only look at the underside of the boulder. People driving in scenic national parks are not known for paying close attention to their driving, and in a time of massive recreational vehicles, this kind of thing just doesn't cut it anymore.

A hat tip to the arrival of spring in the Sierra Nevada...the redbuds were in full bloom up the canyon, providing a splash of vivid color on the dark green slopes.

Although not as colorful as redbud, the ceanothus shrubs added a wonderful fragrance to the air. The bees and other pollinating insects were in heaven.

As we went further up the canyon, Moro Rock loomed ever higher above us. The granite rock of the dome expanded as the rock was exposed at the surface. The plutonic rock tended to fracture parallel to the surface, which had the effect of removing corners and edges from the rock outcrop, eventually leading to the formation of the dramatic dome. The process is called exfoliation. It would be so cool to climb the dome, but we knew that most of the park access roads would be closed because of the winter snowpack.

Except that they weren't. When we reached Giant Forest, there were a few snow patches here and there, but the snowpack is currently at half the normal level. All the roads were open, so we headed over to the Moro Rock trailhead. As dramatic as the dome is, trail access is easy because the CCC put in a stairwell to the summit. Easy that is, if you don't have problems climbing 300-400 steps. The views in the clear spring air were stunning.

Immediately across the Kaweah Gorge were the Castle Rocks (9,000+). The spires and towers of granitic rock exhibit the other result of rock expansion: jointing. When the fractures that result from pressure release are vertical, they allow water to get into the narrow spaces. If the water freezes it expands, wedging the rock apart. The water also aids in the chemical weathering of the rock, so as time goes on the cracks widen, forming the prominent spires.

Moro Rock is best known for the wonderful perspective it provides on the Great Western Divide. The mountains are often hidden from view by other high ridges or thick forest, but Moro Rock stands out from the mountainside, and the view is tremendous.

With the covering of winter snow, one can imagine the glaciers that carved the horns, aretes, and cirques that are so well exposed here. Cirques are the bowl shaped basins on upper ridges where the glaciers accumulated. Aretes are the knife-edged ridges that divide glacially carved valley, and horns are the sharp pointed peaks that result when glaciers pluck rocks from the base of the cliffs in the cirques and aretes. The Matterhorn in the Alps is a familiar example, but there are many horns to choose from on the Great Western Divide.

I have not yet had the privilege, but the High Sierra Trail winds its way from Crescent Meadow in Sequoia to the summit of Mt. Whitney and the Whitney Portal trailhead. It is 60+ miles long, and crosses two major passes, and it must be a marvelous adventure. It is second only to the John Muir/Pacific Crest Trail in popularity.

The picture below illustrates the difference between glacial erosion (the cirques and horns in the upper part of the photo), and the weathering and exfoliation that happens at the lower elevations (the domes both right and left of center).

Moro Rock also provides a wonderful view west towards the Sierra Nevada foothills and the usually invisible Central Valley. You are looking at the most polluted air in the United States: Bakersfield and Fresno. It's not entirely their fault, as they don't necessarily produce more pollution per capita, but the towns are surrounded by high mountains, so they can't blow their pollution into someone else's area the way other municipalities are able to. The photo below is as clear as I've ever seen it from Moro Rock.

Next, we took a look at some trees with a unique geologic history...