Archive for the ‘other’ Category

Suiseki 2011

19 June 2011

This weekend was the 16th annual show by the California Suiseki Society, held at the Lakeside Garden Center. This is what it looked like.


In my amateur opinion, it was a strong show with a lot of variety in its 35–40 stones. Nearly all the entries were from California with a heavy emphasis on the northern Coast Range. The photos below are a few of the stones that impressed me—but there were many more that were too hard to photograph well. Unlike last year, the exhibitors picked a background paper with a color that seemed a little too intrusive to me. But you’ll see how my camera did. I’m not going to comment on the styles of the suiseki because I’d surely botch them. But the rocks themselves are generally familiar stuff, like this dark slate.


I’m always taken with the serpentinite conglomerate of which there are several excellent examples each year.


This blue-green Klamath serpentinite is by Tony Saraceno. I have a nice streamworn boulder of it at That’s not a suiseki, just a specimen.


This one is by Tom Colby. Not everyone filled out their cards, but I like to acknowledge the collectors when I can.


Felix Rivera collected this nice serpentinite. He’s the founder of the society; see his site at where the society’s home page lives.


And Bob & Polly Gould exhibited this exquisitely weathered marble from Southern California. At least, I think it’s marble. Doesn’t matter.


Look for the next show in mid-June 2012, right here in Oakland.

Caldecott Tunnel and the Orinda Formation [updated]

17 May 2011

caldecott tunnel

Those of us in the geology community have been eager to hear more from the Caldecott Tunnel’s fourth bore project. The bore is cutting through the Berkeley Hills in a perfect transect, allowing geologists to sample every meter of the rocks along the way. This weekend, I heard some news in a presentation at the CalPaleo 2011 meeting.

The east end was where the boring began. The Orinda Formation is beautifully exposed there—most of it, anyway—on both sides of Route 24.

orinda formation

Much of it is coarse conglomerate of late Miocene age, about 10 million years old, that’s thought to represent landslides into a freshwater basin in the middle of volcanic terrain.

orinda formation

That part, naturally, has no fossils because the environment was too rugged for even large bones to survive. But there’s other stuff in the Orinda, like lava flows at the top of the unit belonging to the Moraga Formation. This is a view of the underside of the lava, where it flowed onto the moist sediments one day long ago.

moraga lava

And there’s a good amount of fine-grained sedimentary rock, suitable for preserving fossils, as you move down section toward the hills. Caltrans has a contract with PaleoResource, a well-regarded firm, to monitor the work and recover fossils that turn up. In the initial digs, the scientists found and cataloged thousands of items, including lots of fish fossils, clams and crabs, birds and the first leaf fossils ever found in the Orinda. The press tends to zero in on large mammals, though, so we’ve heard about bones from wolverines, horses, rhinos, camels, pronghorns and even the obscure oreodont.

However, PaleoResource scientists have told me that Caltrans has not allowed the paleontologists into the tunnel proper, in violation of the contract and the agency’s own policies. That’s the kind of thing that makes me awaken at night and grind my teeth. Not only are we not learning about the lower Orinda Formation, we’re not studying the transition into the underlying Claremont Formation and the Sobrante Formation on the west side.

I try to take the long view. The tunnel is being dug in three passes, and conceivably the rocks can be sampled later. But PaleoResource officials have told me their contract runs out this summer, before the next phase of digging.

So I try to take a longer view. Once upon a time, nobody cared about paleontology. Heck, they didn’t care about archaeology. Today, turning up a human bone will stop a job in its tracks. Fossils aren’t that disruptive; they can be salvaged and documented in a day or two. Many agencies and jobs go well, the paleo people and the construction people interacting well and yielding good science. Other jobs are jobs from hell, but the long arc of history is curving toward respect for science.

Update: I’ve put up some photos of new fossils from the dig on KQED Quest Science Blogs.

Geological Designs

19 February 2011

Block by block, I’m exploring Oakland. In West Oakland there isn’t much geology, but it has a thriving (or at least widespread) stone district. This small fabricator is on Peralta Street.

geological designs

This steel sign above the lovely window screen shows that the company name is actually “designs,” not “design.” So does Google.

geological designs

Stone, like concrete, brick and aggregate, is among the first things a new settlement demands. Like their wares, stone dealers seem to hang in there for the long term. I find them charming, but of course even stone has fads and trends and every other challenge a business experiences. The extra challenge of a stone business, I suppose, is gravity.

Stone shops tend to cluster around heavy transport, and an old rail line runs past this address. Other stone yards occur in East Oakland near the tracks there. And another common site for very specialized stone businesses is near cemeteries. I often stop and admire the monument shop on Piedmont Avenue just down from Mountain View Cemetery.

By the way, I have a new gig with KQED Quest as one of their science bloggers. My posts go up Thursdays at

Fake rocks

28 January 2011

The Hillcrest School, up in upper Rockridge/Broadway Terrace, has a beautiful campus with gardens, trees and this play structure.

fake rocks

I wish it were real rocks. Of course the artificial outcrop is good for encouraging unstructured play, confidence using one’s body and all the rest. The lessons it teaches will serve the kids well as they move on to indoor climbing walls and other safe amusements. But I cherish grit, lichens, little holes with secrets inside, moss, roughness that scratches to get your attention. I favor visual texture, variegation, the presence of minerals in their cryptic typicality, the possibility of fossils. I want kids to explore wild rocks in wild places, even if it’s only a roadcut or a vacant lot. I think these kids deserve a real, local knocker, the kind their neighborhood abounds in. We have enough fake rock in our Disneylands and along our freeways.

Thank you.

Northbrae rhyolite

27 December 2010

Berkeley is full of interesting rocks, many of them preserved in pocket parks. The most prominent of these is Indian Rock.

indian rock

Click the photo for a 1000-pixel version. Some 100 years ago this tough rhyolite, a volcanic rock very high in silica, was mapped as part of the same rock body as the one in Leona Quarry and farther down along the hills. But a master’s student at Cal State Hayward gave it a good look in the 1990s and determined that the Northbrae rhyolite, as this occurrence was named, is quite a different rock. (In fact the Leona rhyolite isn’t considered a rhyolite any more, but rather a high-silica welded tuff/volcaniclastic sequence.) Whereas the first mappers thought that both rocks were Pliocene, which is quite young (about 5 million years), the Leona was later shown to be Jurassic (about 150 m.y.). The Northbrae is not that old, but neither is it as young as Pliocene. It’s just a little older than the Moraga Formation basalt and the volcanic rocks of Sibley volcano, about 11 million years, making it Miocene. It came out in that same episode of eruptions, which today sits to the north around Clear Lake and The Geysers.

And it’s still definitely rhyolite. Rhyolite is the stiff, slow-moving lava that makes up little volcanoes like the young dome inside Mount St. Helens, or the rugged knobs of the Inyo Domes, over the Sierra in the Mammoth Lakes area, or farther south in the Coso Range. It makes great rock for climbers—strong, imperishable, full of handholds and rarely giving way under a person’s weight.

The rhyolite of Berkeley is well worth a visit. Just go at a time when the climbers aren’t busy; the rock parks swarm with them in nice weather. I don’t think Oakland has any of this rock, but it might.


22 September 2010

A few places in Oakland feature these sandstone blocks. Two I can think of immediately are on Lakeshore Avenue, including this one.

sandstone blocks

I always wonder whether the stones were salvaged from somewhere else, like Andy Goldsworthy’s wonderful “Stone River” on the Stanford campus. They have tool marks on them, and I don’t know much about stonecarving tools, but I’ll bet they haven’t changed in centuries. These stones echo the most ancient practices of civilization, in which building stones were recycled again and again without regard to the structures they previously gave life to. The stones were precious in bulk rather than as individuals, the way that gold bullion is precious.

These stones always remind me, every time I see them, of one of William Randolph Hearst’s greatest follies. He purchased an ancient chapter house, built in Spain by Cistercian monks in 1190, and shipped it to California as disassembled stones. He never got around to putting them back together again, and as I recall the story, they sat in a pile somewhere in Golden Gate Park. (That’s probably an exaggeration, but who knows?) Now those stones were precious in the way that old gold coinage is precious—they embody history. These days we are a sentimental people, and the Spanish stones have a bit of holiness in them, as if the monks’ prayers had saturated them. Scattering them on the ground in a strange land is an affront to their previous owners.

That’s why I loved today’s Tribune column by beer writer Jay Brooks. A California branch of the Cistercians, the Abbey of New Clairvaux north of Chico, has acquired the stones and plans to reassemble the chapter house using the profits from a series of Trappist-style beers to be made by Sierra Nevada Brewing next year. The Trappists are the order of monks that include the Cistercians, and they’re famous for brewing Belgium’s greatest beers. That’s worth a toast.

San Francisco suiseki

1 August 2010

Last month the California Suiseki Society had its 15th annual show in the Lakeside Garden Center. It was a sublime exhibit with an attentive audience.


The best photo I got that afternoon is this stone by Jim Broadhurst. See more of the stones here and here.


There is an older suiseki society across the bay, San Francisco Suiseki Kai. They are such purists that until recently they did not even use English, but their current president, Janet Roth, is an Anglophone. Their 29th annual exhibit is coming up next weekend: August 7 and 8, 10 am to 4 pm, in the Japan Center, at the Union Bank Hospitality Room at 1675 Post Street. The collectors themselves award winners of the exhibit by voting for their favorite stones. Me, I love finding out where the stones come from, then scratching my head in happy confusion at the mixture of thoughts, aesthetic and geologic, that arise as I contemplate them.

Janet Roth couldn’t resist saying in her note to me announcing the show, “Of course, if the legislature outlaws serpentine we will be in a pickle.”


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