Where the Sierra Nevada Rises from the Sea: Pfeiffer Big Sur State Park

Where the Sierra Nevada rises from the sea...in our last post, we found out how the Santa Lucia Range of the Big Sur Coast can be thought of as a part of the Sierra Nevada, being made of granitic and metamorphic rocks that were sliced off the south end of the Sierra and carried north by motion along the San Andreas fault. It's usually only missing the "snowy" part of the "Snowy Sawtooth Range (it always sounds better in Spanish), but in my readings, I found out that the north end of the range was actually called the Sierra Nevada early on.

We are continuing our random and arbitrary exploration of the most beautiful coastline in the world. We started our journey at Limekiln State Park, and Julia Pfeiffer Burns State Park would have been the next park to explore, but I gave it a detailed treatment here in Geotripper only four months ago. It may have the most scenic cove of all, given the presence of beautiful McWay Falls right on the beach.What we are doing instead is heading north up Highway 1 a few more miles, and a bit inland, to check out Pfeiffer Big Sur State Park.

Truth be told, Pfeiffer Big Sur State Park can hardly be called a hidden treasure. It is visited by half a million people a year. It has a nice campground complex tucked beneath the redwood trees, and a small inn and restaurant. The park is traversed by the Big Sur River which despite a long dry season runs all year.

Ridge trails provide airy views of the rugged mountains, while others might prefer to explore up the riverbed narrows.

The coast redwoods in the park are stunning. Ronald Reagan, in his early political years as a candidate for governor was once quoted as saying "if you've seen one redwood, you've seen them all". He didn't actually say that, but he did say something essentially as bad: "I think, too, that we've got to recognize that where the preservation of a natural resource like the redwoods is concerned, that there is a common sense limit. I mean, if you've looked at a hundred thousand acres or so of trees - you know, a tree is a tree, how many more do you need to look at?"

As Snopes points out, the statement was in the context of a pitched battle to save the remaining old-growth forests of Coast Redwoods in the northwestern corner of California (which culminated in the establishment of Redwoods National Park in 1968). And it is a fair question to ask, if the only point of preserving the tree is to have a forest that people and go and visit like a museum while we cut down the rest. The thing is, we did cut down the rest. In a century, we cut down 95% of the original redwood trees that existed when Europeans first discovered California. Is that a common-sense limit?

As it is, there is a string of pearls, the national and state parks that stretch along the California coast from Big Sur north to the Oregon border, but there is no longer an intact Coast Redwood ecosystem. The species of animals and plants are now trapped in isolated islands, and many are under severe pressure from lack of suitable habitat and suburban sprawl.

Pfeiffer Big Sur State Park is one of those islands. It is so far south, into the drier central California climate, that it was a biological island even before humans arrived. The trees can only survive in the sheltered canyons, in the microclimates that are cool enough and wet enough to allow the survival of the biome. With global warming, the survival of the trees here is even more tenuous as the years go forward. A vast wildfire (the 160,000 acre Basin Complex Fire) burned through the region in 2008, and it is not clear if the vegetation growing back will be like that which existed before.

In the meantime, the forest at Big Sur is a treasure, and an environment that evokes serenity. When I visited a few months back, I took the short hike up Pfeiffer Creek to little Pfeiffer Falls.

Granted, there weren't a whole lot of rocks to look at, but the views across the canyon were nice, giving a good perspective of the terrain (one can say it's also a good view of a terrane, but that's a geological in-joke). The ridge across the canyon is made of Franciscan rocks, and a major fault related to the San Gregorio fault system runs through the canyon below. Granitic and metamorphic rocks dominate the foreground ridge.

The falls are modest, more a pleasant turnaround point along a scenic hike than a destination. But the hike was delightful.

In late July, the setting sun shone directly through the canyon, providing light for far longer than I expected. While the rest of the state was sweltering, we were enjoying the natural air-conditioning provided by the nearby shoreline, and the night-time temperatures were mild as well. It was great base camp for our exploration of the Big Sur. But be sure to get your reservations early! They go fast.

Next, we head out to a Big Sur beach that isn't so easy to find (and I'm not going to make it any easier!).

"Another Earth" showing at the State Theatre, Modesto on Nov. 10

What happens if you meet yourself? What would you have to say?

To all of my Modesto area readers: I want to let you know about a great film series going on at our historical State Theatre in the downtown area (1307 J. Street). Science on Screen pairs films with a plot that includes a scientific component with experts in the field. Last month we paired "Spiderman" with a spider expert, with some very cool live arachnids in the lobby. This Sunday we are screening the movie "Another Earth", and our speaker will be Dr. Jim Hetrick, professor and chair of physics at the University of the Pacific (UOP) who will discuss the physics and astronomy in the film.

Another Earth stars William Mapother (Ethan in "Lost"), and Brit Marling (who also was one of the screenwriters) in a drama set at the time of the discovery of another Earth that might be a near exact match to our own planet. The planets in parallel Universes were identical up until the moment they became aware of the existence of the other. Tragedy at the time of discovery might not have happened on Earth II. Maybe.

The film was the first for director Mike Cahill, and when screened at the Sundance Movie Festival, it received a standing ovation and several accolades, including the Alfred P. Sloan Prize for "focusing on science or technology as a theme, or depicting a scientist, engineer or mathematician as a major character."

The State Theatre in Modesto is a wonderful 1930s vintage movie house that recently underwent a complete renovation. It is a marvelous place to watch a movie and other shows. We will have displays and activities in the lobby prior to the movie, which starts at 3:00 PM. The doors will open at 2:00.

Science on Screen is supported by a grant from the Alfred P. Sloan Foundation, and is a local effort to increase science literacy in our region. I've been on the steering committee for the last year and a half. It's a great program. I hope that my friends and readers in the area will take advantage of this great opportunity and come out for the show! More information can be found at the facebook page for the State Theatre at https://www.facebook.com/events/1426917090862479/. The website for the State Theatre at http://www.thestate.org/.

We have three more films in the Science on Screen series for this season: Whale Rider will screen on Sunday, January 12, Blue Butterfly on March 9, and Avatar on March 31. We also have a special program on April 13, Physics and Fastballs, a presentation by a recently retired Exploratorium expert on America's greatest sport (yeah, argue all you want).

Where the Sierra Nevada Rises from the Sea: The Big Sur Coast

Sierra: "A rugged range of mountains having an irregular or jagged profile, like a saw blade"

Sierra Nevada: A mountain range in California with the shape of a tilted block, composed largely of granitic and metamorphic rock (from the Spanish "snowy saw-tooth range").

The Sierra Nevada? Rising out of the sea? What's that about? The Sierra Nevada, California's well-known mountain range with Yosemite and all that is 80 or 90 miles away to the east, across the Great Valley. We are at the beach, so why are we talking about the Sierra Nevada?

You can look at the mountains of Big Sur (the Grande South!) as being a sierra in the sense of being quite rugged. Our location today, Limekiln State Park, is located along the Big Sur Coast north of San Simeon. The mountains here have never been glaciated, but the peaks above the park seem to be rather inaccessible. And they rise nearly a mile out of the surf (nearby Cone Peak is 5,155 feet high and only a little over two miles from the coastline). That certainly makes it a "sierra". But the Sierra Nevada?

The shoreline cliffs don't seem to recall the Sierra Nevada. The cliffs are composed of metamorphic basalt and graywacke sandstone of the Franciscan Complex, rocks that formed in the trench of a subduction zone that was active up until a few tens of millions of years ago

It's when you look at the boulders in the creek at Limekiln that you start to realize that there is a different sort of connection to the actual Sierra Nevada that lies so far to the east.

The boulders of Limekiln Creek are composed of granitic and metamorphic rocks that look a great deal like the rocks found in the southern Sierra Nevada and adjacent Mojave Desert. They are in fact the same rocks. The rocks are way out of place, a hundred miles or more from where they originated. But they are the rocks of the Sierra Nevada, and as such, the Santa Lucia Range, rising out of the Pacific Ocean, can literally be considered a part of the Sierra Nevada..

As to how they got here in Central California, one need look no further than California's favorite fault, the San Andreas.

The crustal slab of granitic and metamorphic rocks of the Big Sur country is called the Salinian Block, and as you can see on the map below the block lies west of the San Andreas (granitic rocks of the Sierra and Salinia are shown in red on the map below). For the last 28 million years or so, the San Andreas has been shifting at a rate of a few inches a year. Inches multiplied by millions of years translates to great distances of offset, at least 195 miles, and possibly more.

Limekiln State Park has a lot going for it these days. It is a second-growth redwood forest that has recovered much of its original beauty. The forest was originally cut down not so much for the lumber, but as the fuel for the lime kilns.

The kilns rise out of the forest like bizarre temples or alien landing beacons. They were built to process marble into lime for construction material, and were active from 1887 to 1890. After the marble was used up, the kilns were abandoned, and the forest slowly grew back. In the 1980s, a private landowner wanted to log the forest again, but many Big Sur aficionados objected and in 1994 Limekiln became a state park. The park has faced problems in its short existence, including a fire in 2008, and closure by the state in 2012 due to the budget crisis.

The park is back, though, and it is a pleasant place to visit. There is a modest campground with maybe two dozen sites with some sites near the beach and others up in the canyon among the redwood trees. It has a half-mile trail to the lime kilns, and a short spur trail to one of the more unusual looking waterfalls to be seen anywhere, 100-foot tall Limekiln Falls. The odd cone-shaped appearance of the fall results from the accumulation of calcium carbonate deposits dissolved from the mountains upstream.

This is the first stop on our exploration of the Central California coast, the most beautiful shoreline in the world (read the intro here if you want to argue the point!)

Seeking Geology Along the Most Beautiful Shoreline in the World: the Central California Coast

Oh, I know that the title of this post is a bit of hyperbole...there are many beautiful coastlines in the world, and you are free to argue for your favorite in the comments. But I think that geology has dealt a special hand to the part of California between San Simeon and Bodega Bay on the California Coast. It's hard to think of a more diverse place of intriguing scenery, with fascinating geological relationships at the same time.

I had two occasions in recent months to explore this most beautiful region; a three day trip with my students, and a spur-of-the-moment camping trip. We didn't visit every beach along the Central Coast, but we found several spectacular state parks, and I was reminded at every turn of the road what an incredible place live in. California is a wonderful place...

Here's a bit of a preview...we'll have a look at Julia Pfeiffer Burns State Park and wonderful McWay Fall, which at times falls directly into the sea.

We'll explore little-known Garrapata State Park, a stretch of beach that is pleasingly deserted much of the time.

Point Lobos State Preserve is better-known, but it also has a wonderful geological story: just where did those incredible conglomerates come from?

 Point Lobos also has some intriguing sea arches.

And Bodega Head...what is the Hole in the Head, and what stupid thing was nearly done here in the 1950s? I hope you will enjoy the journey!

The Way it Was Today: Yosemite Valley in November

What a wonderful week! I had the privilege of visiting the most beautiful place in the world twice in the space of a few days. It's true I was taking a bunch of students with me, but we were learning geology in one of the most spectacular settings possible and it was a fine and enthusiastic group. For some it was their first visit to the valley. For others it was the first time seeing the place in a geological sense.

It was an eventful week as well. A storm blew through, leaving a few inches of snow in the valley, but it was all but gone by the time we arrived this morning. Last week there were lots of leaves on the trees in full glory of color, but things were dusty. Today the ground and air were moist, the forest smelled sweet, but there were fewer leaves on the trees.

Our first stop was to visit the Tunnel View, a spot just a few hundred feet below where the valley was first discovered by Europeans in 1851. There was trouble between American settlers and the local Native Americans, so a militia had been raised to search them out. Their medical officer Lafayette Bunnell was entranced with the valley and wrote a glowing account of its beauty.

I seemed to be concentrating on Half Dome a lot today. We had arrived in a large bus, and buses aren't allowed to park in many parts of the valley, so we toured on the free trams with appointments to meet at several locations. I elected to walk between points, and had a few new angles with which to view the iconic chunk of granitic rock (granodiorite, to be specific).

Despite the appearance, the dome is not really in half. It might be more properly called Three-Quarter Dome, although I prefer the Native American name of Tis-sa-ack. The south east flank is a classic exfoliation dome, shaped by the slabbing off of the corners and edges in response to the release of pressure as the rock was exposed by erosion. The steep northwest face is a joint surface that was exploited by glaciers that flowed beneath the face of the dome.

There are other lesser known domes, such as North Dome, seen below. It is the rounded edge of a long ridge of granitic rock. Like Half Dome, it was formed by exfoliation. Glacial ice never covered it. North Dome lies above Tenaya Creek, across from the face of Half Dome.

I was walking from Yosemite Lodge to Happy Isles. I started by wandering through the forest in an unfamiliar direction and almost immediately discovered the central receiving facility for all the raw sewage in the valley (I don't know this for sure, as the building was locked and unlabeled, but the stench was convincing). I reconsidered my route and headed out to the meadow near Sentinel Bridge. I was rewarded with a beautiful panorama of the Cathedral Rocks and the Three Brothers (below).

I said there were fewer leaves, but they certainly weren't gone by any means. Fewer leaves means that the remaining ones stood out in bolder relief.

The Merced River continues its late season serenity. Low flows provide marvelous reflective properties. The picture below is from a stretch of the river just downstream of the tent cabins at Curry Village.

The ravens were out in force. I stopped for a snack and they were flanking me. When I got up to discard my trash, they were thinking about seeing what was left in my pack. I found myself imagining that they will be the next truly intelligent being to evolve after we humans are gone. Like us, they seem capable of surviving practically anywhere (the deserts of Death Valley to the high peaks of the Sierra Nevada and across the desert southwest), and they are probably already smarter than the average touron in Yosemite (it's how they stay fed).

After meeting with the students at Happy Isles, we started back across the valley to Yosemite Lodge. I decided to walk and see if I could beat the tram. I did, by about 10 seconds (Unlike the tram, I didn't have to stop, and I could take the shortest route along roads and trails). I snapped a few shots while rushing along the road. Below is another view of North Dome, and a side of the Royal Arches, a form of exfoliation in reverse.

Washington Column is a steep cliff that overlooks the Mirror Lake area. The largest slide known from Yosemite Valley occurred here a few thousand years ago, forming the lake (that is a lake only seasonally). It may have been about twenty times larger than the biggest historical mass wasting event, the Middle Brother slide of 1987, which involved 600,000 cubic yards of granitic rock.

As I got closer to our final stop, I had one more wonderful view of Half Dome. The late afternoon sun was casting dappled shadows across the meadow. It was another beautiful day in a wonderful place. In a few more short weeks it will be winter!

You Think Your Halloween Monsters are Scary? Imagine What Your Ancestors Thought About These Terrifyingly Real Beasts...

(Modified from my post of June 8, 2011)

Happy or scary All Saint's Eve or Halloween, whatever your pleasure might be. As you cheer on the zombies and alien predators extorting candy from you, give a few thoughts about what would have been really scary: the terrifying animals that humans lived with many centuries ago.

Have you ever wondered why shadows are so effective in the best horror movies? It's pretty clear to me that there is a collective genetic memory in all of us of the monsters that we think of as myths today, but which were horribly real as recently as 12,000-13,000 years ago. The world was full of creatures that wouldn't have minded dining on us, and deep in our collective consciousness is a reflexive response to particular shapes and shadows. The pareidolia I wrote of once was a survival mechanism; we needed to see those faces in the underbrush in time to climb or flee to safety.

So who belonged to that mysterious shadow above? It was a short-faced bear, Arctodus simus, that lived in my home region, the Central Valley of California. Grizzly bears were a common presence in California when the Europeans arrived two hundred years ago. They described many of the native Californians as bearing wounds of encounters with the grizzlies, and compared to spears or arrows their guns were not much better as a defense against them. The short-faced bear was bigger, maybe 2,000 lbs or more. It may have been the largest mammalian predator ever.

There were roving packs of Dire Wolves, Canis dirus, as large or larger than their cousins in Canada or Alaska...

...and there were the Saber-tooth Cats, Smilodon fatalis, (below) along with the American Cheetah (Myracinonyx sp.)  and the Scimitar Cat (Homotherium serum). We have been living with the comforting insulation of modern civilization for a long time, but even a glance at a skeleton of these long extinct creatures can awaken nightmares in the recesses of our brains.

This museum display in Sydney gave me the willies...

If you want to see the rest of these creatures in a slightly less threatening atmosphere, check out the Fossil Discovery Center of Madera County, which opened for business a few years ago. The fossil creatures on display were found by the bulldozers of the Fairmead Waste Facility. They were digging a garbage dump, and found a treasure trove of fossil bones; 27 species of mammals and a half dozen other creatures dating from the Pleistocene. I find it to be a wonderful science resource for the region. It is well worth a visit.

Fossil Discovery Center of Madera County

19450 Avenue 21 ½
Chowchilla, CA 93610

Take the Hwy 99 Exit 164, SW corner of Road 19 ½ & Avenue 21 ½

That Volcano is Dead Right? There's No More Hot Magma? Bumpass Hell at Lassen Volcanic National Park

"Now, I don't know,  I don't know where I'm a gonna go, when the volcano blow"
Jimmy Buffett

Mt. Tehama is long gone, and Lassen Peak blew off all her accumulated stresses and frustrations with the eruption in 194-17, right? I mean, it's all a national park now, and that means it's like an amusement park and the park service would never allow the volcano to go erupting on all the tourists, right?

Actually, the Lassen Volcanic Center is on the short list of the most likely sites of volcanic activity in California, according the the California Volcano Observatory. And there is plenty of evidence that hot magma still lurks beneath the surface in the national park: there are five active geothermal areas in the park boundaries.

It was the last day and the last stop of our late September field studies adventure through the Cascades of Northern California. We had explored the Castle Crags, Mt. Shasta, Lava Beds National Monument, Medicine Lake Highland, and McArthur-Burney Falls, as well as Chaos Crags, Lassen Peak, and Mt. Tehama in Lassen Volcanic National Park. Our destination was Bumpass Hell, at the end of a spectacular 1-1/2 mile hike.

Bumpass Hell was named after an early pioneer rancher in the area, Kendall Bumpass who had good reason to call this place his hell: he inadvertently put his leg through a thin crust of silica and plunged it into the boiling acidic water beneath. He eventually lost the leg.

Being the most active geothermal area in the park, one might think that Bumpass Hell sits atop the magma chamber, but it actually lies a mile or two east of the body of molten rock (which sits at a depth of about 3 miles). Water at depth is heated until it turns to steam at temperatures exceeding 400 degrees, and the steam rises along fractures and fault lines where it condenses and reacts with local pockets of groundwater. The water is general highly acidic, and emerges at the boiling temperature (as discovered by Bumpass and numerous careless tourists who choose not to heed caution signs).

In a general way there are four kinds of geothermal features, and three of them can be viewed at Bumpass Hell. If it is the dry season, there might not be very much water and the vents will be filled with the clay and mud formed from the decomposition of the surrounding andesitic volcanic rock. The mucky cauldrons are called boiling mudpots. These acidic pits are definitely not recommended for facial care schemes.

The black sludge in the picture below is made of finely divided particles of iron pyrite (fool's gold). That might be counter-intuitive given the familiar brassy luster of the mineral, but geology lab students will recall that the streak (color of the powder of a mineral) is black.

More familiar features are hot springs. Hot springs can be found in many geologic settings, including along fault lines, but volcanic hot springs are in a class by themselves. They are not the kind of springs that one would want to be soaking in. The temperatures at Bumpass Hell are at the boiling point, and as previously noted, the water is highly acidic.

If there is not very much water available, for instance in the late summer or fall, steam vents will be common. They are called fumaroles. Fumaroles are a good spot to see sulfur crystals growing (see the picture below). At the top of my list of worst possible jobs would be that of sulfur miner. I've seen articles on mine workers in South America who have to climb into volcanic craters and scrape off the sulfur crystals from active fumaroles, risking scalding burns and the scarring their lungs by breathing in the acid-rich air.

The only type of geothermal feature that is not found at Lassen Volcanic National Park is a geyser. Geysers like those found at Yellowstone National Park (where something like 70% of all the world's geysers are found) require very specific conditions underground that are not present at Lassen. The main reason is probably that the rocks and magmas at Lassen are not as silica-rich as those at Yellowstone. The groundwater plumbing maze beneath Yellowstone is coated with silica deposits which produced a closed system in which the pressures can build high enough to produce the spouting fountains. There are too many "holes" in the plumbing at Lassen.

Does the presence of magma underground at Lassen mean that an eruption is coming soon? It's hard to say. It may be that the eruption of Lassen in 1914-17 really did relieve pressure and stress in the magma system and that the magma today is simply cooling off and solidifying. This is suggested by the relative rarity of eruptions at Lassen (the recent event, Chaos Crags a thousand years ago, and the formation of Lassen around 28,000 years ago). But it could also be that the magma chamber still has an eruption or two left in it. In any case, we can be fairly confident that we will know something is afoot, because magmas don't sneak up to the surface without causing other forms of mayhem, such as earthquakes, changes in ground elevations, gas emissions, and increased geothermal activity.

I'll be watching. And when everyone else is running away from the eruption, me and lots of other geologists will be trying to get closer!

I hope you've enjoyed this little vignette on the Cascades of Northern California. Look for an exploration of the central coast of California next!