Archive for the ‘Other topics’ Category

The armored shore

17 August 2020

Oakland’s shore is not what it used to be, not at all. The only hint of how it was is Arrowhead Marsh, part of the Martin Luther King Shoreline Park: a broad wetland laced with tidal creeks and vegetation for all gradations of water from fresh to salt.

And yet even Arrowhead Marsh is reputed to be an accident, formed when Anthony Chabot’s dam, under construction in the hills, had a failure that washed huge amounts of sediment down San Leandro Creek. To fans of nature this history, true or not, is scant comfort.

The geologic map (in this case the map of non-bedrock deposits in USGS Open-file Report 2006-1307) shows that every foot of Oakland’s original shore has been erased and built upon, with the small possible exception of the western tip of Adams Point.

Radio Beach at Oakland’s north edge, our nearest thing to a natural beach, exists on landfill.

Everything in the Oakland Harbor complex, from the Outer Harbor to the military grounds to the airport, is on landfill — “made land” as the old-timers called it.

Coast Guard Island is an artificial pile of Bay sediment, built with dredging spoils.

Alameda doubled its land area by dredging and piling. It’s all there on the map.

East Creek Point, the little peninsula of made land directly east of Alameda on the shore of San Leandro Bay, is a good place to contemplate this great undertaking, its aftermath and its possible futures.

Sitting here in 1852, when Oakland was first incorporated, this scene was a luxuriant marsh like that shown in the 1857 Bache map of San Antonio Creek where the Harbor is today. (The photos in this post are extra big, so click for the full experience.)

From here the view shows nothing of what once was, other than the water and the distant mountains across the Bay. The scene was a planar surface of green and blue, with added brown mudflats at low tide. There were no sharp lines between land and sea; none of the trees on the Corica Park golf course or anywhere else on Bay Farm Island; no brown hill covering a former landfill; no palms and wharves and homes — no ground at all — on the Alameda side; no riprap boulders on this side.

All the land in this view is “reclaimed” from marsh or built outright. Sandy mud was dug up from the Bay floor, crushed rock freighted down from quarries, sand and gravel carried in from excavations elsewhere, construction waste dumped on the shore. Trenches drained the marshes, removing the water to create low-lying land for development.

Even much of the water is artificial, in that it exists by virtue of dredging the Tidal Canal. From initial planning to dedication, the massive project took 28 years, every dollar intermittently funded by Congress. Here’s the canal’s east end from the High Street Bridge. An extension dug across San Leandro Bay is called Airport Channel.

Like the rest of the shore, the canal is heavily armored from end to end.

But what we have reclaimed, nature works to claim back. Around the bend from East Creek Point, the gentle Bay surf winnows out the finer grit and exposes the construction debris holding up the weedy shoreland.

The made land is wearing down, and rising sea level will accelerate the decay. There are two ways to deal with that, and both will be used as the century proceeds: more armoring, and returning the sharp shoreline to gentle transitional marsh. This restored marsh is a start. Similar projects are under way in Alameda, especially in the former military zones.

The “made water,” for its part, is filling up. The harbor needs regular dredging to stay open. That will never end as long as water flows and sediment is carried to the sea.

Finally, the made land is prone to its own problems. In this example near the west end of the High Street Bridge, the ground has settled around the water main in the last 80-plus years. Eventually something will need to be done.

It turns out that the Tidal Canal didn’t work as planned. It was supposed to allow the tide to flush through the Estuary and save the work of dredging the ship channels. That didn’t happen, but now we can’t fill it back up. What an alternate history we would have if it hadn’t been built.

Black geology matters

8 June 2020

Since my last post two weeks ago, the dreams of black Americans, deferred so often and so long, have once again exploded. I’m at risk for the Covid virus and not the type to join a march; still I have support to offer from this peculiar pulpit.

Geology is the whitest science in America. The geoscience community knows this, doesn’t like it, and keeps trying different ways to remedy it. I know this, I don’t like it, and I keep trying here in what I hope is a neutral way to expose you, whoever you are, to the geological wonders of this most excellent place. My hope is that adults will catch a spark of insight from me and pass it around, or nurture it within themselves, and bring this special side of our landscape into Oakland’s public affairs and popular culture for everyone’s benefit.

The special sauce of science is its neutral, trans-human point of view, in which new knowledge is born from the encounter between nature and the pure intellect. This viewpoint feels natural to folks like me, born in suburban white America to educated parents with good intentions. It’s an ideal that fosters a freedom to follow our curiosity wherever we wish.

My life since childhood has been one of dawning, then growing awareness that I grew up within a historical and political system with deep taproots in racism. Our inner lives are affected by how white people treat us. Duty calls upon white people in general to see this clearly and act accordingly. This post aims mainly at people like me.

That neutrality so tempting in science can be treacherous by masking us from ourselves. Inevitably, what we are affects what we see. To illustrate this point, I bring you the life of the notable geologist Joseph Le Conte. Well, a few years ago in this space I brought you the shallow, all-lives-matter version of his life. Since then I’ve looked more deeply and have more to say.

Joseph Le Conte was born on a Georgia plantation in 1823 and spent a cloistered, pampered childhood there. From the earliest days his mind sought the purity of nature and the comfort of social order. He passed the Civil War as a loyal Southerner in all respects. Le Conte first visited the Sierra Nevada in 1870, chaperoning a slapdash horseback expedition of Cal’s first undergraduates. In 1875 he published an edited version of his notes as “A Journal of Ramblings through the High Sierras of California.” (The Sierra Club reprinted it in 1900.) In the entry for 25 July, their fifth day on the road, comes this jarring passage:

Soon after leaving the plains, we stopped for water at a neat hut, where dwelt a real “old mammy,” surrounded by little darkies. On inquiry I found she was from Jackson County, Georgia, and formerly owned by a Mr. Strickland. She had come to California since the war. I was really glad to see the familiar old face, and hear the familiar low-country negro brogue; and she equally glad to see me. She evidently did not like California, and seemed to pine after the “auld country.”

That Le Conte saw fit to publish this vignette, deliberately and after reflection, says much about his and California’s deeply ingrained racism, but I want to note that it reveals the depth of his self-deception. This is the reminiscence of someone raised in “free plantation life” on the throne of white boyhood, but who never had to wield a whip on a human being or sign a human being’s bill of sale with his own hands (his share of the family’s property had an overseer).

By excusing the life he was born to on the basis of racialized Darwinism, he could wash his hands in pure intellectual water. It was only pure scientific truth and plain fact, he long argued, not a matter of malice or evil, that blacks were low and whites were high. And the lofty white intellects he prized most were in polite agreement (or mild, polite disagreement) with him. The key was that the men were articulate, mutually respectful and never raised their voices.

This man had a prominent role at UC Berkeley for thirty years, where he taught geology. He was named to the National Academy of Science in 1875. (“I might have been elected sooner,” he wrote in an autobiography, “but for the iron-clad oath of uninterrupted loyalty to the United States, which of course I could not take.”) He wrote textbooks and taught classes and all the while gave high-minded cover to the vicious forces of discrimination. Today UC Berkeley’s geoscience department is first-rate — I have no aspersions at all to cast on it — but it has a history embodied in its campus home, named Le Conte Hall.

We didn’t raise a statue to Le Conte, but we have erected monuments with his name on them: a Sierran peak, a college building, a city street, a children’s school and so forth. Those things are fair game for discussion and action. We are not to blame for our history, but we are responsible for it.

To get back to the moral, the neutrality of science is only the promise, not the guarantee, of a benign worldview or a neutral career. It’s not fair of me to suggest otherwise. What do white geologists owe this moment? I say we need to offer more effective help to those who don’t enjoy our privileges, people who are minoritized. They have reasons not to see the world as a reasonable place. They have reason to suspect our science as part of white hegemony.

A Change.org petition for geoscientists (which I’ve signed) puts this part of the problem well: “Geoscience is intimately tied to fossil fuels, mining, environmental contamination, atmospheric pollution, water quality, natural hazards, parks and tourism, and climate change. Black, Indigenous, and Latinx People and other minoritized groups are disproportionately impacted by limited access to these resources, and the negative impacts of each of these.”

We also need to admit that the minoritized have real reasons to beware being out in the wild, poking at rocks and acting unusual. I’ve encountered people who challenged my presence, and I know it’s easier being white. The minoritized need our full support in visiting the outdoors freely, without fear.

Of course black folks are doing their own work, through organizations like Outdoor Afro (founded right here in Oakland), the National Association of Black Geoscientists, the American Association of Blacks in Energy and others. For its part, the Geological Society of America presents a prize each year, the Bromery Award, to worthy scientists from minoritized communities. Nearly every awardee mentions the special problems that nonwhite geologists experience.

But white folks need to open up, open up more, and do their part. For my part, I recognize that each of Oakland’s communities has its own idea of what the hills mean, what earthquakes mean, what the land around them means, who got the benefit of our natural resources and who did not. I’ve visited every bit of this town, including places some folks fear to go, and everywhere I’ve learned something about the variety of human and natural experiences Oakland contains. I want to listen harder, study deeper, avoid unintentional offense, spread knowledge and cheer, and help in whatever ways I can to set things right.

In search of lime

25 May 2020

I like to brag that Oakland contains more rock types within its boundaries than any other city in America. But alas, it’s missing one of America’s most widespread rock types: limestone. Yes, there are pods of dolomite limestone in the Claremont Shale, but that’s a far cry from what Oakland’s first outside settlers hankered for, which was real calcite limestone.

Limestone is essential for civilization because it’s the default industrial source of lime (calcium oxide or hydroxide), without which you can’t manufacture any kind of decent mortar, or plaster, or cement. Lime has been made for thousands of years by simply roasting limestone, which consists of the mineral calcite (calcium carbonate). This was traditionally done in a lime kiln, a stone furnace that was loaded with rock and firewood.

The Bay area does have bodies of limestone, and these were staked out early. But the nearby firewood supplies (i.e. forests) were soon depleted, and the industry was fitful and limited until reliable supplies of coal and, still later, oil became available.

One alternative to limestone in Oakland was oyster shells, which we once had in abundance. Unfortunately, many of the old Native shellmounds had oyster shells in abundance too, and this led to the end of them.

A few years ago I had the chance to visit the remains of an old-fashioned lime kiln in the Santa Cruz Mountains.

Another old site was on the coast near Rockaway Beach, south of Pacifica. I wrote a piece about it for KQED a while back that explains where most of our local limestone comes from, tectonically speaking.

This kind of industry lasted only a few decades. Around the turn of the last century, big manufacturers started to mine massive bodies of limestone. One was on the Santa Cruz County coast at Davenport; it supported a company town out there for a whole century. Another was in the South Bay near Cupertino, based in a quarry on Permanente Creek. One of Henry J. Kaiser’s early companies operated it, and when Kaiser eventually became head of an industrial giant, during World War II he took the name Permanente for the name of his innovative company health-care plan. The quarry is still digging, almost 80 years later.


By Steve Jurvetson from Menlo Park, USA – Flickr.com – image description page, CC BY 2.0, from Wikipedia commons

Another big limestone quarry was in American Canyon, in Napa County. But the one that fascinates me most is the former Cowell lime quarry, which sits between Walnut Creek and Concord, on Lime Ridge. For about 40 years, starting in 1908, this quarry exploited a thick deposit of travertine — hot-spring limestone. It supported a company town too. Now some of the workings are in Lime Ridge Open Space, where you can scrutinize these unusual deposits. They aren’t like anything else around.

This post was inspired by my maniac brother Steve, who explores the woods around his Lyme, New Hampshire home to locate old cellar holes. Now he’s branched into old lime kilns.

In other news, I’m happy to report that the latest Covid-19 guidelines now allow the use of public transit for outdoor recreation. This means that all of my geology walks and rambles can be undertaken again, and I’m looking forward to getting out there, taking due care of course.

Geologists at Mountain View Cemetery

16 March 2020

Longtime readers will recall my post about Joseph Le Conte’s gravestone, which begins, “Joseph Le Conte (1823–1901) is probably the most eminent geologist in Mountain View Cemetery.” Last week I looked into that statement in more detail. Having made a thorough study — well, fairly thorough — actually pretty cursory, given the difficulties, I can say that Prof. Le Conte is probably not the most eminent geologist buried here. It’s arguable.

Here are all the other geologists I’ve been able to find, in the order of their deaths.

Ezra Slocum Carr (1819-1894) lies in plot 4, in an unmarked grave next to his wife Jeanne Smith Carr (1825-1903).

Ezra is significant in American geology for being part of the 1857 geological survey of Wisconsin, along with James Hall and Josiah Whitney. Ezra was a professor of natural history at the University of Wisconsin when Jeanne met a remarkable young man named John Muir. Together, the Carrs — no other word for it — cultivated him and maintained with him an intimate lifelong connection. Ezra gave Muir his first instruction in geology, something the Scottish-born farmboy must have soaked up like a sponge. When Ezra accepted an appointment to the new University of California in 1869, he became its first professor of agriculture. Muir had already come to California and been smitten with the Yosemite country. Jeanne arranged for Muir to meet Louisa Strenzel, daughter of a wealthy Martinez doctor and orchardist, who became Muir’s wife in 1880. Ezra later became the state Superintendent of Public Instruction.

James Graham Cooper (1830-1902) lies in plot 31, lot 15 right across from the prominent knocker. I haven’t found his stone yet, if there is one.

Cooper was a restless guy, trained as a doctor as so many early American naturalists were. His interests included botany, zoology and fossils, and he made many contributions to paleontology. He served in several Western exploring expeditions, most notably Josiah Whitney’s geological survey of California. He lost out to Joseph Le Conte as first professor of natural history at UC Berkeley, but still crammed a lot of accomplishment into his lifespan.

The remains of John C. Merriam (1869-1945) are in the columbarium, which is hard to navigate so I haven’t visited his niche yet. Instead here’s a fine, unengraved boulder of Franciscan chert in the middle of a plot.

If you’ve heard of California’s tar pits — the major ones in Rancho La Brea in Los Angeles and near McKittrick in the San Joaquin Valley — Merriam was the guy who led the first scientific excavations there on behalf of UC Berkeley. He described Smilodon californicus, the sabertooth cat, our official state fossil. He also co-founded the Save the Redwoods League, ran the Carnegie Institution and was president of the Geological Society of America for a term. The UC Museum of Paleontology has a page about him, as does Wikipedia.

Andrew C. Lawson (1861-1952) was buried at Mountain View but later removed to Toronto, presumably in a family plot up there but that’s where the trail ends. Here’s my favorite outcrop of Franciscan chert at the cemetery — Lawson gave the Franciscan complex its name.

Lawson, another Scottish immigrant, was very influential through his long tenure at UC Berkeley. He was the first decent mapper of Bay area rocks and a demanding instructor, emphasizing rigorous fieldwork. Many of the rock units around here were named by him. And of course he did heroic service after the 1906 earthquake, heading the Carnegie Commission that thoroughly studied the event in the aftermath. His two-volume report, published in 1908, is still known among seismologists as “the Lawson report.” He recognized and named the San Andreas Fault — wags suggest that he’d indirectly named it for himself. The mineral lawsonite is named for him.

But for my money, this guy buried in plot 6 is Mountain View’s leading geologist.

Nicholas Taliaferro (1889-1961), of the old Kentucky Taliaferros, pronounced his name “TALLifer” but his colleagues and students knew him as “Tucky,” presumably because of his accent. At UC Berkeley he succeeded Lawson in teaching field geology, up in these hills. In a Bay Nature piece in 2010, Erik Vance described Taliaferro’s teaching style, a story I used to hear too: “He would walk into the hills with his students, lean back on the head of his axe, stare at a rock, and light a cigarette. The confused students would look around, try to figure out what he was staring at, and start taking measurements. After a bit, Tucky would stand, wander to another rock, and have another smoke. If you missed it, you missed it.”

He ran the department’s Geology Summer Camps for 33 years, training more than a thousand future geologists to make sense of the land around them. And when he wasn’t doing that he patrolled the Coast Range and Sierra foothills, covering some 50,000 miles on foot and mapping 26 whole quadrangles, a land area probably exceeded only by the late Tom Dibblee. Every paper on Coast Range geology of any depth will cite Taliaferro’s work, even today. UC Berkeley has memorialized him on this page.

I would love to learn of other geologists buried at Mountain View. Or, for that matter, at any other Oakland cemeterySt. Mary, Home of Eternity, Home of Peace or Evergreen.

There is one more prominent California geoscientist I found: Eugene Hilgard (1833-1916), UC Berkeley’s first mineralogy professor, but far better known as a pioneer soil scientist. He’s in St. Mary, in the Dormitory B section.