The California state rock is serpentine (correct name, serpentinite), which comes in many varieties, some which contain asbestos, which doesn’t get dangerous unless you grind it up and spread it into the air. Just sitting there, as it does through much of California and in other parts of the world, serpentine is mostly a greenish grace on the landscape.
Serpentine’s provenance is also remarkable (at least to geology types like me). It’s formed deep in the planet’s crust, under the spreading centers of oceans, where sea water penetrates mantle rock and, under great heat and pressure, lends lustrous colors and textures to what would otherwise become the plain old peridodite.
Or let the paleontologists dig it for you. That’s what a team led by Yale researchers did last year in southeastern Morocco’s Lower and Upper Fezouata Formations. The result is covered by LiveScience in Oldest Soft-Bodied Marine Fossils Discovered . Specifically, “The animals represented by these newly discovered fossils, including sponges, annelid worms, mollusks, and horseshoe crabs, lived during the Ordovician period between 480 million and 472 million years ago, making them the oldest ever discovered during this period.”
With your help, dear readers and fellow geobloggers, I’d like to run an experiment in social geology this summer. My hypothesis is that real-time/live-web tools and social networking can be applied to geology-focused road trips in ways that enrich the experience for both the road-tripper and the audience of active participants. This blog post is a call for collaborators, and a starting point for discussion and refinement of this hypothesis. I hope that it evolves into much more than that.
Me too. While Ron traverses The West, I’ll be heading to France for much of June and July. But I’ll keep up with him and enjoy vicarious digging of hard rock landscapes, many of which I already know but haven’t seen. Sez Ron,
The response to my blog poststwo weeks ago using excerpts from John McPhee’s Annals of the Former World has inspired me to attempt to GigaPan at least four more of his I-80 geologic localities on my way out to San Francisco. Tentatively, and subject to tight restrictions imposed by the vagaries of weather and the need to arrive at the conference on time, I’m aiming to GigaPan the Gangplank/Summit area of the Laramie Range, roadcuts in the Rawlins, WY area, something in the Rock Springs/Overthrust area of western Wyoming, the Wasatch Front/Great Salt Lake, the Golconda Thrust, and an ophiolite in the Sierra Foothills.
The only thick book I’ve picked up nearly as often as McPhee’s Annals is Tolstoy’s War and Peace (though the latter not in the last couple of decades, I regret to admit). The Gangplank and the Overthrust sites I have visited dozens of times in re-readings of Rising from the Plains, my favorite of the four prior books that Annals combines (with a bonus section called Crossing the Craton). The Wasatch, Salt Lake, Golconda thurst and Sierra Foothills ophiolites star in Basin and Range and Assembling California, which Annals also includes. Been to all of those many times as well.
Ron is a Gigapanner of the first water. Here’s the latest, shown with a Canon 5D like my own (though with a better lens than any that I have). Can’t wait to see what he shows. (Some samples from his professional work as a geology professor.)
Good to see by his tweets (he’s @rschott) that he’s still cruising the West Coast (after getting some gigapans in Utah en route ). While he’s still out there, here a few possible side trips I’d like to suggest :
Love Ranch, where David Love grew up. Love was the geologist who guided McPhee through Wyoming. The title of the resulting book, Rising from the Plains, comes from a diary of David’s mother, Ethel Waxham Love, a writer whose prose was equal to McPhee’s, and who carries much of the book’s narrative burden. Dr. Love and the ranch buildings are all gone, but not the landscape, nearly all the features of which were named by the Love family.
Red Bluff Ranch, near Lander and west of the Gas Hills, amidst red Triassic features raised to weather when the Wind River Range, said David Love to John McPhee, “just pooched out.” Red Bluff Ranch is where Ethel Waxham (years away from becoming a Love) arrived when she — as McPhee loves to put it — came into the country by stagecoach.
Storms are as much a part of nature as old growth forests, even when the former reduces the latter. Sad to read, however, that mosquito abatement has involved the draining of the woods’ pond, where generations of kids learned to skate in a beautiful setting.
For perspective perhaps it is helpful to note that the boggy parts of Borg’s Woods are among the few vernal remnants of glacial Lake Hackensack, which pooled over most of the Hackensack River watershed when the last ice age began to end around 15,000 years ago. The lake lasted several millennia, then drained around 11,500 years ago, when the terminal moraine near Perth Amboy broke. Back then the sea was still far outside the current borders of New York and New Jersey. Only when the rest of the ice cap melted did the oceans reach their current level — which, as we know, is still rising.
Meanwhile, back here in Boston, a winter snowstorm is headed our way, after treating D.C., Maryland and the surrounding regions to another heavy layer of snow, atop the deepest in memory, which hasn’t had a chance to melt. (One relative there went for many hours without power, looking out on a scene where his car appeared only as a low hill in snow through which only trees and houses protruded.) We’ve mostly been spared this winter, as have the ski areas to the north. Those will probably be spared again, since this storm is expected to do its heaviest dumping south of here. Bummer, that.
On Friday we fly back to Santa Barbara for The Kid’s winter school break. There are mudslide risks there too, though not as severe as in Los Angeles. (Our hills are mostly rock. L.A.’s are mostly dirt. Think of L.A.’s hills as sponges — because that’s what they are. Place a dry sponge on a steep incline, drip water on it, and see what happens when it fills.)
Maybe, if we’re lucky, we’ll miss the rain there, and get treated to some of those sunsets we’ve been missing. Hope so.
[Later...] I just got a call from my wife, awakened at 3:3oam in California by a call from the school here. A snow day has been declared. Doesn’t look like it yet, though. There are details in the clouds, like scales on a mackerel. But, as we can see from the radar, it’s coming.
[Later still...] It’s now 2:30 in the afternoon, not long before school gets out, and there has been approximately no snow at all. Just a mix of light flakes and drizzle. Good, I guess.
For most of Winter in the Northeast, skating is possible only during the somewhat rare times when the ice is thick and not covered with snow or other unwelcome surface conditions. And bad skating has been the story, typically, for most of this Winter around Boston. After an earlier snow, there were some ad hoc skating rinks cleared by shoveling, but those were ruined by rains, more snow, more rains, and intermittent freezes that made a hash of the surface. But recent rains and hard freezes have formed wide paths between remaining islands of ruined snow. On most ponds there aren’t enough open spaces for real hockey games, but there’s plenty enough for skating, and for hockey practice, anyway. (A note to newbies and outsiders: nearly all lakes here are called ponds. Dunno why yet. Maybe one of ya’ll can tell me. Still a bit of a noob myself.)
Hockey practice is what I saw when I paused to take a sunset shot with my phone at Spy Pond, which I passed it late this afternoon on a long walk along the Minuteman Bikeway, which is one of my favorite walking paths (and thoroughfares — at least when it’s warm and clear enough to bike on). As it happens, Spy Pond ice has some history. There was a period, in the mid- to late-1800s, after railroads got big, but before refrigeration came along, when New England was a source for much of the world’s shipped ice. And Spy Pond itself was one of the most productive sources. This picture here…
… shows ice being harvested for storage in ice houses beside the railroad which is now the Bikeway. I stood near the left edge of this scene when I took the picture at the top, and the boy and his dad playing hockey were about where at the center left, where a horse is shown pulling what looks like a man with a plow. (That last shot is from this historical display alongside the bikeway.)
There are now 120 of my shots in Wikimedia Commons. I put none of them there. I just tag shots aggressively and describe them the best I can (and have time for), and let nature take its course. In these cases nature was PDTillman. Hats off to him.
It’s a live recording of the slide that killed ten people in LaConchita, California, on January 10, 2005. We know people who knew people who were killed in that slide. The story of the Wallet family is especially tragic. Jimmy Wallet was walking back from a corner store with some ice cream for his family when the mudslide in the video above destroyed his house before his eyes, burying his wife and three little daughters. Only he and his teenage daughter, who was out with friends, lived. Six others also died.
I’ve been listening to KNX, which has been reporting on the heavy weather in Southern California, and I’m amazed to hear that a large percentage (40%, I think the reporter said) of evacuees are waiting it out.
Here’s the deal, folks: mudslides are inevitable. If you live below a steep hill or mountain slope in a part of Southern California that’s getting heavy rain, and you’re under an evacuation order, get out. Right now (5:45pm Pacific), Acton. La Crescenta, La Cañada-Flintridge, Glendale, Tujunga Foothill and Sierra Madre all have a total of nearly 2000 homes under evacuation order. (So says the official speaking at a news conference on KNX right now.)
In Los Angeles versus the San Gabriel Mountains, it is not always clear which side is losing. For example, the Genofiles, Bob and Jackie, can claim to have lost and won. They live on an acre of ground so high that they look across their pool and past the trunks of big pines at an aerial view over Glendale and across Los Angeles to the Pacific bays. The setting, in cool dry air, is serene and Mediterranean. It has not been everlastingly serene.
On a February night some years ago, the Genofiles were awakened by a crash of thunder — lightning striking the mountain front. Ordinarily, in their quiet neighborhood, only the creek beside them was likely to make much sound, dropping steeply out of Shields Canyon on its way to the Los Angeles River. The creek, like every component of all the river systems across the city from mountains to ocean, had not been left to nature. Its banks were concrete. Its bed was concrete. When boulders were running there, they sounded like a rolling freight. On a night like this, the boulders should have been running. The creek should have been a torrent. its unnatural sound was unnaturally absent. There was, and had been, a lot of rain.
The Genofiles had two teen-age children, whose rooms were on the uphill side of the one-story house. The window in Scott’s room looked straight up Pine Cone Road, a cul-de-sac, which, with hundreds like it, defined the northern limit of the city, the confrontation of the urban and the wild. Los Angeles is overmatched on one side by the Pacific Ocean and on the other by very high mountains. With respect to these principal boundaries, Los Angeles is done sprawling. The San Gabriels, in their state of tectonic youth, are rising as rapidly as any range on Earth. Their loose inimical slopes flout the tolerance of the angle of repose. Rising straight up out of the megalopolis, they stand ten thousand feet above the nearby sea, and they are not kidding with this city. Shedding, spalling, self-destructing, they are disintegrating at a rate that is also among the fastest in the world. The phalanxed communities of Los Angeles have pushed themselves hard against these mountains, an aggression that requires a deep defense budget to contend with the results. Kimberlee Genofile called to her mother, who joined her in Scott’s room as they looked up the street. From its high turnaround, Pine Cone Road plunges downhill like a ski run, bending left and then right and then left and then right in steep christiania turns for half a mile above a three-hundred-foot straight-away that aims directly at the Genofiles’ house. Not far below the turnaround, Shields Creek passes under the street, and there a kink in its concrete profile had been plugged by a six-foot boulder. Hence the silence of the creek. The water was not spreading over the street. It descended in heavy sheets. As the young Genofiles and their mother glimpsed it in the all but total darkness, the scene was suddenly illuminated by a blue electrical flash. In the blue light they saw a massive blackness, moving. It was not a landslide, not a mudslide, not a rock avalanche; nor by any means was it the front of a conventional flood. In Jackie’s words, “It was just one big black thing coming at us, rolling, rolling with a lot of water in front of it, pushing the water, this big black thing. It was just one big black hill coming toward us.”
In geology, it would be known as a debris flow. Debris flows amass in stream valleys and more or less resemble fresh concrete. They consist of water mixed with a good deal of solid material, most of which is above sand size. Some of it is Chevrolet size. Boulders bigger than cars ride long distances in debris flows. Boulders grouped like fish eggs pour downhill in debris flows. The dark material coming toward the Genofiles was not only full of boulders; it was so full of automobiles it was like bread dough mixed with raisins. On its way down Pine Cone Road, it plucked up cars from driveways and the street. When it crashed into the Genofiles’ house, the shattering of safety glass made terrific explosive sounds. A door burst open. Mud and boulders poured into the hall. We’re going to go, Jackie thought. Oh, my God, what a hell of a way for the four of us to die together.
The parents’ bedroom was on the far side of the house. Bob Genofile was in there kicking through white satin draperies at the paneled glass, smashing it to provide an outlet for water, when the three others ran in to join him. The walls of the house neither moved nor shook. As a general contractor, Bob had built dams, department stores, hospitals, six schools, seven churches, and this house. It was made of concrete block with steel reinforcement, 16 inches on center. His wife had said it was stronger than any dam in California. His crew had called it “the fort.” In those days, 20 years before, the Genofiles’ acre was close by the edge of the mountain brush, but a developer had come along since then and knocked down thousands of trees and put Pine Cone Road up the slope. Now Bob Genofile was thinking, I hope the roof holds. I hope the roof is strong enough to hold. Debris was flowing over it. He told Scott to shut the bedroom door. No sooner was the door closed that it was battered down and fell into the room. Mud, rock, water poured in. It pushed everybody against the far wall. “Jump on the bed,” Bob said. The bed began to rise. Kneeling on it — on a gold velvet spread — they could soon press their palms against the ceiling. The bed also moved toward the glass wall. The two teen-agers got off, to try to control the motion, and were pinned between the bed’s brass railing and the wall. Boulders went up against the railing, pressed it into their legs, and held them fast. Bob dived into the muck to try to move the boulders, but he failed. The debris flow, entering through windows as well as doors, continued to rise. Escape was still possible for the parents but not for the children. The parents looked at each other and did not stir. Each reached for and held one of the children. Their mother felt suddenly resigned, sure that her son and daughter would die and she and her husband would quickly follow. The house became buried to the eaves. Boulders sat on the roof. Thirteen automobiles were packed around the building, including five in the pool. A din of rocks kept banging against them. The stuck horn of a buried car was blaring. The family in the darkness in their fixed tableau watched one another by the light of a directional signal, endlessly blinking. The house had filled up in six minutes, and the mud stopped rising near the children’s chins.”
Note that these flows don’t happen only when it’s still raining. Here’s one that happened along the Hayward Fault, in Fremont, that I remember watching from across the South Bay when we lived in Emerald Hills, California, in the late Nineties. It moved slowly and didn’t take out any houses; but it almost did, and was dramatic to watch. It wasn’t raining at the time. The mountainside was saturated with water from earlier rains, and chose its own time to give.
In terms of Geology, California is new. If you were to run a short video of the last few hundred thousand years in Southern California, you’d see a riot of mountains forming, sliding sideways and collapsing. If you were to do the same for the mountains of Arkansas or North Carolina, you’d see almost nothing happening.
Living anywhere is a game of russian roulette with nature: a bet that grand geologic or weather events will not occur within our brief lifespans. In communities like La Conchita, and others placed below dirt sure to move, there are many more bullets in the chambers.
But denial is a powerful force. When I first moved to Santa Barbara, and drove past La Conchita on Highway 1, I was astounded that anybody would chance to build there, because big landslides had obviously happened already, and more were sure to come. Since the mudslide of 2005, many people continue to live in La Conchita, and insist that the county “fix” the mountain above them — even though geologists have studied the region closely and said this:
The 1995 and 2005 landslides in the 200-m high sea cliff above the community of La Conchita, California, are known to be part of a reactivated Holocene prehistoric landslide. We propose that the prehistoric Holocene slide is part of a much larger, several hundred million cubic meter late Pleistocene slide complex composed of upper slumps and lower flows, informally termed as the Rincon Mountain megaslide.
On the positive side, rain on SoCal’s low elevations in winter means snow on the high peaks. If the air clears, Los Angeles will be flanked by white alps. I guarantee great skiing on Mt. Baldy when this thing is over. Provided there isn’t a debris flow blocking the road going up there.
John McPhee is the best nonfiction writer alive. My opinion, of course. But I happen to be right. Nobody describes anything better. No writer does a better job of digging into subjects most would find dull (rocks, pine barrens, river levees, minor species of fish) and making them not only interesting but relevant. Sometimes extremely so.
Take what he wrote in The Control of Nature about the Mississippi river, describing, among much else, what would happen to New Orleans when a levee failed. Which, ineviably, one would. In a chapter titled Achafalaya, McPhee handicapped the Army Corps of Engineers against the Mississippi. That was in 1987. The New Yorker ran it again in 2005, after Hurricane Katrina gave McPhee’s words the ring of phophesy.
Another chapter in The Control of Nature is “Los Angeles vs. The San Gabriel Mountains.” That one has special relevance today, when torrential rain on mountains denuded by fires brings the threat of mud slides — a term that doesn’t describe what really happens. McPhee:
In the blue light they saw a massive blackness, moving. It was not a landslide, not a mudslide, not a rock avalanche; nor by any means was it the front of a conventional flood. In Jackie’s words, “It was just one big black thing coming at us, rolling, rolling with a lot of water in front of it, pushing the water, this big black thing. It was just one big black hill coming toward us.”
In geology, it would be known as a debris flow. Debris flows amass in stream valleys and more or less resemble fresh concrete. They consist of water mixed with a good deal of solid material, most of which is above sand size. Some of it is Chevrolet size. Boulders bigger than cars ride long distances in debris flows. Boulders grouped like fish eggs pour downhill in debris flows. The dark material coming toward the Genofiles was not only full of boulders; it was so full of automobiles it was like bread dough mixed with raisins. On its way down Pine Cone Road, it plucked up cars from driveways and the street.
Geologists call mountain-building “orogeny.” In his Pulitzer-winning book on geology, Annals of the Former World, McPhee explains, “in the fight between orogeny and erosion, erosion always wins.” Fires side with erosion. Rain does too, especially when teamed with fires.
It is important to understand, if you live on or under their slopes, that the mountains of Southern California are brand new and not all well built. There are volcanoes that grow slower than some of these mountains, and come down slower too. Many of the canyons and ravines in the San Gabriels — the Big Tujunga, the Pacoima — are flanked by dirt whose angles of repose nearly exceed the temporary frictions that hold the land in place. Water-soaked dirt can weigh more than rock, and will seek a level lower than its own. Burn off the desert chapparal that carpets the slopes, and debris flows become certain once the rain soaks in.
So that’s not just what to watch for in the current heavy weather. It’s what to expect.
I posted a lot today, but nothing matters more — or has been more on the front of my mind — than Haiti. What hell that such an already troubled country should be hit by an earthquake so bad, and so close to its most dense population centers.
So, as I try to get my head around the situation, here’s a list of links, in the order that I visit them:
There are mountains, and there is the Matterhorn. It’s all a matter of sculpture and presentation. Great art, great framing.
The Matterhorn is ice sculpture. It was carved by ice out of rock pushed to the sky by a collision between Italy and Europe that’s still going on. The ice was as high as the mountain, or higher, and the carved off parts are scattered all over the Alps and its alluvial fans, discarded by water and wind when the ice cap melted, only a few millennia before the Pyramids showed up. Go back to when the ice was at high tide, and the Alps looked like the near-buried parts of Greenland do today. (See here, here and here.)
The shot above was what the Matterhorn looked like by moonlight on our way back to the hotel tonight. There’s hardly a thing on Earth more impressive than that.