Andrew Alden

@geology

Geology lifer Book: Deep Oakland: How Geology Shaped a City Monthly newsletter: deeperoakland.substack.com Fortnightly blog: deepoakland.com aboutgeology on Xitr Webmaster N Calif Geol Society: norcalgeolsoc.bsky.social Personal: andrewalden.bsky.social

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Andrew Alden@geology· 18d

CAUTION GRANITE CURB

Andrew Alden@geology· 19d

"The Trump administration hates academic science funding, full stop." Straight words in the current issue of Science. www.science.org/content/blog...

From Derek Lowe in the latest issue of Science: "The Trump administration hates academic science funding, full stop. They hate where that money goes, and they hate who it goes to. They want to keep all that money for themselves, to hand out to favored cronies who can help them get elected and to steer yet more money and more power back into their hands.

That’s it. That’s the story. They are naturally not putting it in those words, but instead talking about “gold standard science” and the “reproducibility crisis” and funding “bold inquiry” for “transformational breakthroughs”. This is all bullshit, and it’s important to realize that.

Andrew Alden@geology· 21d

Looks like a proper tectonic quake (now M5.1) in the Texas panhandle. Deep disposal well activity is a possible trigger but that's TBD. (earthquake.usgs.gov/earthquakes/...)

clip from https://earthquake.usgs.gov/earthquakes/map/ showing M5.0 event NE of Amarillo with steep oblique normal focal mechanism pasted on.

Andrew Alden@geology· 28d

Today's outing

Sandstone of the Redwood Canyon Formation framed by manzanitas

Andrew Alden@geology· 29d

My bus tour of Wrangell, Alaska, last month began as our guide passed around this specimen of almandine garnet. There's a former mine north of town where collecting and marketing the garnets is restricted to the town's children. Most of the garnets are small, but not all of them.

Fat 3-cm dark red garnet in a gray laminated matrix

Andrew Alden@geology· 29d

Shungite, the weirdest mineral(oid) I ever owned, is a pyrogenic hydrocarbon with way-low 13C: new paper in Geology (pubs.geoscienceworld.org/gsa/geology/...). More in the alt text

$Dark gray chip approx 4 x 4 cm with US penny for scale. Material resembles obsidian in fracture and luster but is much lighter and warmer in the hand. My old article on shungite is at https://web.archive.org/web/20140710202954/http://geology.about.com/od/mineral_resources/qt/What-Is-Shungite.htm$

Andrew Alden@geology· Jul 14

Some graywacke I looked at and put back on Saturday. There is no end to rocks!

Hand specimen of broken blond medium-grained gritty looking sandstone with a variety of grains from a neighborhood roadside.

Andrew Alden@geology· Jun 30

Distal turbidites at Prince Rupert, BC

Closeup of slate-grade turbiditic argillite exposed in a construction cut, light and medium gray with some small reddish zones.

Exposure of turbidite rock. Lush greenery in this very rainy setting has not yet covered the fresh cut. Boulders on the ground are mostly unrelated.

Andrew Alden@geology· Jun 28

Port Frederick (Hoonah), Alaska today. Good for whales, seals and sea otters!

Abundant gray clouds cover the mountains flanking a sea passage extending to a hazy distance. A light rain is falling in a cold breeze upon gently rippling steel-gray water.

Andrew Alden@geology· Jun 27

Local lichens on Sitka rock

Boulder the size of a medium boulder in Sitka Alaska, black basalt covered with lichens of various grayish hues

Andrew Alden@geology· Jun 25

Gulf of Alaska looking its best

Indigo-gray sea, scattered stratocumulus, clear horizon and a wide ship's wake stirring the water to a rich glaucous hue. Off frame to right, the St Elias Range rises, some 200 km distant, a low mottled fringe bisected by a thin wedge of cloud.

Andrew Alden@geology· Jun 24

Harvard Glacier; Smith glacier feeding it at left

Happy people at the rail of deck 15 admire a glacier filling the field of view; Chugach Mountains behind with more feeder glaciers

Andrew Alden@geology· Jun 24

Seward, Alaska

Cloudy day. Square two-story building clad in dark iridescent tile ranging from magenta through spruce green to deep purple. Letters on the side read "Seward Community Library & Museum"

Other face of the building with the local Kenai Mountains framing it

Andrew Alden@geology· Jun 21

Approaching Hubbard Glacier

Snowy jagged St Elias Range and smooth, ice-strewn Disenchantment Bay frame a wide, bluish tidewater glacier

Andrew Alden@geology· Jun 20

Johns Hopkins Glacier

A wide blue glacier winds out of the rugged Fairweather Range to a calm, ice-strewn expanse of cloudy water in Glacier Bay, Alaska

Andrew Alden@geology· Jun 20

Stout flight at Klondike Brewing in unique Skagway

Trail Coffee blonde stout, 2nd Ave territorial (local sources) stout and The Revenant BA stout (aged 2nd Ave; 4 yrs old, last barrel made by the late founding brewer). All of them intense. The BA is especially touching. Not shown: Whipsaw spruce ale for my viamin C. If I lived here I could live on this one brewer.

Andrew Alden@geology· Jun 18

Lupine season under way in SE AK

Four blue-indigo lupines opening from their bases in front of mossy rock wall

Andrew Alden@geology· Jun 17

Entrance to my favorite name water body: Fords Terror

Placid green water, furrowed by cruiseship's wake, in front of narrow high-walled inlet with a vigorous meltwater freshet cascading out of hanging valley on right side. Sea-level passage curves quickly left out of sight.

Andrew Alden@geology· Jun 17

Recent retreat of Endicott Glacier

Bare rock zone ~100 meters up the fjord side with dark weathered lightly vegetated rock above, topped with low clouds, greenish cloudy seawater below, smooth, with scant brash and bergy bits

Andrew Alden@geology· Jun 12

I'm off to sea tomorrow. Here's where I went last weekend on the NCGS field trip.

Wave-polished bluish-gray diorite of the Salinian block at Bodega Head, half buried in coarse blond feldspathic sand.

Polished striated serpentinite boulder protrudes from brown sand at Shell Beach on the Sonoma coast.

Gray striped high-grade metagreywacke of the Goat Rock block in Franciscan melange. Ferocious wind not visible.

Closeup of well-rounded iron-stained cobbles in Late Cretaceous conglomerate on the Russian River just east of its mouth. A split cobble displays its coarse-grained plutonic nature. Rock is a dead ringer for the familiar Oakland Conglomerate of similar age and origin: a deep-sea basin outlier of the Great Valley Sequence.

Andrew Alden@geology· Jun 4

Bill Bakun recounts the Parkfield EQ prediction experiment in Seismo Research Letters (pubs.geoscienceworld.org/ssa/srl/arti...)

"Somebody, most likely John Filson, the USGS Office of Earthquakes, Volcanoes, and Engineering (OEVE) chief and my old friend, decided that I should be the First Chief Scientist of the Parkfield Earthquake Experiment. I found this out when two branch chiefs, Bill Ellsworth for Seismology and Wayne Thatcher for Tectonophysics, walked into my office and shut the door. One branch chief is a load, but two in my office with a shut door was very intimidating. I do not remember what they said, but they promised to provide support. I said whatever to get them out of my office. A few minutes later, Al Lindh walked in. Al told me that both of us were 5 yr too late for the plate‐tectonics revolution, contribute to earthquake prediction, the next big thing in seismology. I told him that I would think about it and tell him the next day. Al was a persuasive guy, and the next day I said yes."

Andrew Alden@geology· Jun 2

I argued that we should give our moons localized names. deeperoakland.substack.com/p/deeper-oak...

"And then there’s the set of names we’re supposed to call each full moon over the course of the year: the Harvest Moon, the Hunter’s Moon and so on. These outsider names come to us from farming lore in Old Britain or tribal traditions in New England (real or fake). Once these names are trapped in the Farmer’s Almanac, they gain the arbitrary status of birthstones and are similarly exploited by media corporations whose business model, like that of a street beggar, is to catch my eye by whatever means necessary.

"I let the Moon in our sky catch my eye. In August our full moon marked the height of blackberry season and the emergence of pink, fragrant belladonnas (aka naked ladies). Both the berries and blooms pop up in all sorts of places and are always yummy (to taste and smell, respectively)."

Andrew Alden@geology· May 30

The June "Deeper Oakland" newsletter goes out tomorrow; subscribe any time. deeperoakland.substack.com

Boulder of autobrecciated greenstone in Peralta Creek, East Oakland

Andrew Alden@geology· May 29

Talus at Davie Tennus Stadium, formerly the Alameda Macadamizing Co. quarry: half argillite, half tennis balls

$Fallen rock bulges a mesh steel fence. A large fraction of it is tennis balls knocked out of bounds by tennis players and never recovered.$

Andrew Alden@geology· May 13

Enough doomposting. How about a nice serpentinite?

Blue-green serpentinite exposed along the footpath at Serpentine Prairie preserve, in the Oakland Hills

Andrew Alden@geology· Apr 25

Sunset at el Arroyo de Loreto

Silhouetted against a golden sky are jagged peaks of the Sierra Gigante, behind the airport control tower and a wide gravel dry riverbed flanked by 10-meter levees.

Andrew Alden@geology· Apr 24

My new favorite thing is sopa de tortilla in Loreto #GSACS26

tomato broth puored into a bowl of crisp tortilla strips with avocado y cotija, sour cream and salsa on the side, and a "Mi Loreto" margarito at Mi Loreto ristorante on Calle Salvatierra

Andrew Alden@geology· Apr 22

View from the poster hall at GSA Cordilleran Section meeting. Yes it's outdoors on a shaded fifth-floor patio, yes it's full of birdsong, yes there's a gentle warm breeze, yes it's the Sea of Cortez

view south, Loreto BCS showing calm sea and long island

view north to boat landing and distant island

Andrew Alden@geology· Apr 21

Harvey Milk Terminal at SFO is so nice everybody here is strolling and gawking and smiling

View south from my comfy chair at gate B9 (benign!) through cool polarizing windows toward runways and SF Bay

Andrew Alden@geology· Apr 16

SRL paper: Seismology AI needs engineering-style followup; pure research isn't enough. pubs.geoscienceworld.org/ssa/srl/arti...