Archive for March, 2014

Local stone

31 March 2014

I always get a kick from old walls around Oakland that are made of local stones. This one is on Loma Vista Avenue, in the upper Laurel.

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Click the image to see a 1000-pixel shot of the whole thing. The mix of blue Franciscan rocks, golden Tertiary sandstones and the occasional reddish chert is distinctive, and it’s nothing that a local landscaping yard would ever offer. Its charm is homely and understated, but authentic.

We haven’t had a working quarry in Oakland for many years, so a lot of these walls are old, or rebuilt. Lovers of local stone today have to scavenge what they can from recycled rocks or their own cellar holes.

Our slides

26 March 2014

A large, deadly landslide in northern Washington has been making news. Smaller ones around here aren’t deadly, thank goodness, but they are sneaky and expensive and everywhere.

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This isn’t a landslide yet, but these concentric cracks in Skyline Boulevard are typical signs of slumping ground. A city with more money to maintain streets would have dribbled tar over these cracks when they first appeared, a year or two ago. As it is, each crack lets rainwater into the hillside where it promotes more slumping. Keeping the road sealed will buy a few years’ time.

This location is underlain by the same incompetent Sobrante Formation that gave the Caldecott Tunnel builders such trouble. But landslides occur in Oakland on nearly every geologic unit, from the lower streambanks to the highest hills.

Fruitvale Station vista

24 March 2014

Sometimes the weather is clear enough, but just hazy enough, to reveal the details of the landscape for quite some distance. A week ago the view down the line from the Fruitvale BART station looked like this.

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I know it’s a small image, so click on it for an annotated 1000-pixel version. Most of the view extends beyond Oakland city limits. The farthest peaks are in the Ohlone Wilderness east of San Jose, some 30 miles away. Once you become familiar with our skyline, it’s never boring.

The Easton & Wilson Quarry

6 March 2014

The Head-Royce School occupies a lovely secluded site next to Lincoln Avenue. Naturally, it was once a quarry.

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Not just any quarry, although its product was ordinary: crushed rock of indifferent quality. It was the quarry for Easton & Wilson, a paving and construction company founded in the late 1890s by Kimball G. Easton and Arthur R. Wilson. (Wilson also partnered with Easton’s brother Stanley in the Leona Heights Quarry.) In approximately 1905, the business was liquidated by transferring its assets to a new venture by Easton and his brother-in-law Warren Porter named Granite Rock Company. The firm is still in business today as Graniterock, which operates a large quarry on the San Andreas fault in Aromas, near San Juan Bautista.

The rock here was described by the state bureau of mines as “a blue metamorphosed sandstone” mixed with softer sandstone and shale that created a lot of waste. It is right at the edge of the Piedmont block of Franciscan sandstone, a district I described in more detail as the Oakmore block. Near the upper end of the school property, the rock walls are still exposed, as seen from Lincoln Avenue.

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Stone magazine reported in 1900 that Easton & Wilson was sued to stop from opening a quarry on Fruitvale Avenue, on the grounds that the blasting would “addle the eggs in the chicken ranches, which form the leading industry in the neighborhood.”

Apparently this ground sat for 60 years after the quarry closed. The Head-Royce School relocated to the property in 1964. The MacArthur Metro gave more details about the school’s history in 2013.


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