While I was in the Bay Area, I did some touristy things, like riding the cable cars.

I think they used the same model for the safety tips sign as for the “watch out for illegal immigrants” signs along I-5 near San Diego.

Riding the cable cars is fun, but as I mentioned before, San Francisco is pretty hilly.

And there is that moment when you’re approaching the top of a hill and your heart skips a beat as you wonder where the road went.

And then you’re going down the hill and you think to yourself, “Wow. If the brakes failed right now, we’d all be dead. Because, you know, you’re basically riding a park bench down the hill.”

That’s actually not the worst hill. On the worst one, I was too scared to move let alone take pictures.

I also went to Alcatraz, because what says fun like a defunct high-security prison?

Don’t drop the soap!

Getting thrown in solitary gets a nice view of nothing once that door is closed, but with the added bonus of knowing that San Francisco is visible through the windows right outside your own personal hell.

The old warden’s house. I guess excellent ventilation is one of the perks of being the head honcho.

There’s a time capsule! I’m not sure I’ll be around when it’s opened, but here’s hoping!

How’d you like to eat three meals a day knowing there are canisters of tear gas hanging right above your head?

Alcatraz is no escape from the hills. They tell you, several times, that the walk from the boat dock to the main cell block is the equivalent of 13 stories. It’s also no escape from the birds. In fact, if you’re afraid of birds, you’d probably want to avoid the place like the plague the birds probably carry.

It’s hard to see in that picture, but there are hundreds, if not thousands of birds down there. They’re everywhere. And the whole island smells like bird crap. You can’t escape it.

While I was on the boat waiting to leave, something set the birds off, and they all took to wing at the same time. It was freaky, like a Hitchcock flick.

And then they started flying over the boat, which left me covering my head in desperation to avoid being a target. And as you leave, the birds mock you from the warning sign, because these prisoners need no help escaping.

While in San Francisco, I ate a ton of sourdough bread. That stuff is addictive. Who knew some meager little bacteria could produce something so wondrous? But I didn’t take any pictures. And for Monique:

Alas, I did not spend all my time in the Bay Area wandering around San Francisco. I also went to the Winchester Mystery House in San Jose. They don’t let you take pictures inside, and I forgot my camera anyway, so here’s a cell phone shot of the outside.

The place is kooky but fun. I love the winding staircases with the teeny-tiny risers, even though they made me dizzy. Hey, can I make a geology link here? I can! the house was damaged quite badly in the 1906 San Francisco earthquake (there used to be a seven story tower but it came out of the quake leaning and had to be demolished) and Mrs Winchester was trapped in one of her rooms for several hours because all the walls were leaning so badly the doors couldn’t be opened. She thought the spirits were telling her that she was spending too much time working on the front rooms, so she immediately boarded them up and never repaired the damage.

I went looking for some geology, and I found some! First, I went to Hayward to find the Hayward Fault. This fault runs parallel to the San Andreas and was the source of an 1868 earthquake which was called, at the time, The Great San Francisco Earthquake. Of course, that moniker was usurped less than 40 years later.

If you look at a map of the Bay Area, you’ll see a lot of valleys running roughly southeast to northwest. These are all caused by accessory faults to the San Andreas, and run parallel to it.

The path of the Hayward fault is easy to see because it separates the flat lands of the bay from the Berkeley Hills to the east. And it runs right through the cities of Hayward and Fremont.

This is a curb at the corner of Rose and Prospect Streets in Hayward. The fault is running right to left right through this curb. I’m standing on the west side of the fault, and the block I’m on is moving north relative to the east side of the fault. I don’t know when this curb was last aligned, but you can see someone marked a line through it in 2006 (it’s a famous curb!).

It hasn’t moved much in the last 5.5 years, but that’s not necessarily a good sign.

In this shot, I’m looking west down Sunset Blvd from Prospect Street and across the fault. The fact that I’m looking down a hill is due to the fault, and you can see some creep in the sidewalk.

This is the old Hayward city hall, which was built, you guessed it, right across the fault. Oops! It was starting to get too expensive to repair the damage caused by continual creep along the fault, so it was abandoned and a new city hall was built a few blocks away. Even though this building is currently empty, it still looks pretty nice (although there a few broken windows) and I saw no external evidence of fault damage.

It seems that this isn’t an isolated problem! Building city halls on top of faults seems to be the thing to do in the East Bay. Because the city of Fremont did the same thing. Then they discovered that the fault ran right between the support columns. Oops!

Well, as part of that complex they expanded the sag pond and made a nice little park around it.

I had mentioned sag ponds briefly before, but I didn’t really explain how they form. And that’s probably because I didn’t really make the geometric connection, but now I get it, so here goes. I talked before about how the “big bend” in the San Andreas causes a local area of compression. That’s because it’s a left hand bend in a right lateral strike-slip fault. If the bend is a right hand one, you get an area of extension. Since compression gives you mountains, extension gives you valleys. And since water tends to collect at low points, you get sag ponds.

faults

Here’s some really bad art to illustrate. (Man, drawing that with a touch pad was really hard, and I’m pretty artistically challenged anyway.) So all three are right lateral strike-slip faults; see how if you were to stand on one side and look across, the other side is moving to your right in all three cases? The left drawing would be a perfectly straight fault. You get only (or mostly) lateral motion. The middle drawing shows a left hand jog which causes compression and mountains. The right drawing shows a right hand jog which causes extension and sagging.

Incidentally, the Fremont park was filled with Canada geese the day I was there. It was also filled with Canada goose poop. Have you ever seen Canada goose poop? I hope they don’t defecate in flight because if one of those hits your car from a significant height, you’re gonna need some body work.

Last part to come soon!

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