Eureka Valley Thinkwalks (spots open) & a rupture!!
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Joel Pomerantz
May 14, 2025, 2:19:43 PM5/14/25
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Hi!
There are still about half the spots open for the May 24 and May 30 Thinkwalks listed below. Please let me know if you wish to join. I’ll accommodate all I can fit, up to 12 people per walk. The one on the 10th was such a great discussion, weather, everything!
Also, here’s a mind-boggling nature moment. Be prepared to have your socks knocked off. Be prepared to watch this half-minute video multiple times. I did NOT take the video, as you will see.
First, watch the video. Then come back and read more of this email.
https://youtu.be/77ubC4bcgRM?feature=shared
[thumb twiddling]
[etc.]
As it happens, we live in earthquake country. Don’t you forget it! This video was taken just a couple days ago during a devastating and deadly quake in Myanmar. OK, now, did you notice the tiny cracks forming in the driveway and think, um that was click-bait and not dramatic? If so, go watch again and look at the power tower in the upper right collapsing, the water tanks on the roof on the left falling and breaking, the dust rising from the rumpling ground in front of that dumped water. AND the entire background land shifting a couple meters to the right!! The split is right under the farther house, causing it to rotate a little. This is an astounding moment and location to catch on video.
The actual rupture—which caused the shock waves you see swaying the camera—is about 19 kilometers below the surface. The surface effect is dramatic, too, and very similar to the type of fault movement we have in our area: Hayward and San Andreas Faults. Slipping side-to-side rather than forcing up or down means the fault type is called “strike-slip”. The subcategory “transform fault” is used for the one in this film. But it’s another strike-slip like ours. If you want to see the result of similar movement (but not as big) go to the parking lot of the Hayward Plunge and look at the misaligned low walls less than 100 feet east of the parking lot, toward the Ward Creek Trail. They are only offset by a few inches but it’s because of this same type of slip, since those recent walls were built. Some paving in the area is split, too.
Never turn your back on the ocean (or the land, I guess!?) and never turn your mind away from natural systems all around you! They are astounding. And important. [more preaching to the choir]
Joel
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On Tuesday, May 6, 2025 at 12:59:12 PM PDT, 'Joel Pomerantz' via Thinkwalks <think...@googlegroups.com> wrote:
Hello to you!
I invite you to an elevated Thinkwalk this Saturday—or one of the other days listed. Please consider reserving a top-notch spot on high!
We will gather a group three separate times (attend only one) to explore and discuss the water features and hydrodynamics of:
Upper Market Street—Eureka Valley from Ashbury Heights to Kite Hill.
(=) Overview of the city—both literal views and water-wise
(=) Discussion of local historical springs and their status
(=) Walking among the hills with a little up-and-down
RSVP to learn of the meeting spot.
I will ask for a donation at the end, cash or electrozap (digital). Suggested range (pre-adjusted for tariffs and/or poverty) is Zero to $48. Throwing meaningless numbers around is all the rage, I hear.
Sat. May 10 10am to noon-thirty [in the past!]
Sat. May 24 11am to 1:30
Fri. May 30 6pm to 8:30
Pick one! Second choice may also be useful.
In other news: The resource that is arguably most useful for historical research in California is on the ropes.
A withheld-funding emergency has hit our state’s main digital newspaper center, which is at UC Riverside. I use it—the California Digital Newspaper Collection—to search old articles all the time. For some reason, CDNC's state funding disappeared for the present funding period. There was some confusion about next year, but turns out it’s this year’s funding that got yanked. Restoring it and ensuring the future may be a separate matter, but right now:
URGENT!!! This resource will go out of existence if they can’t raise what they need within eight weeks. Contribute what you can at
California Digital Newspaper Collection
cdnc.ucr.edu
There are still about half the spots open for the May 24 and May 30 Thinkwalks listed below. Please let me know if you wish to join. I’ll accommodate all I can fit, up to 12 people per walk. The one on the 10th was such a great discussion, weather, everything!
Also, here’s a mind-boggling nature moment. Be prepared to have your socks knocked off. Be prepared to watch this half-minute video multiple times. I did NOT take the video, as you will see.
First, watch the video. Then come back and read more of this email.
https://youtu.be/77ubC4bcgRM?feature=shared
[thumb twiddling]
[etc.]
As it happens, we live in earthquake country. Don’t you forget it! This video was taken just a couple days ago during a devastating and deadly quake in Myanmar. OK, now, did you notice the tiny cracks forming in the driveway and think, um that was click-bait and not dramatic? If so, go watch again and look at the power tower in the upper right collapsing, the water tanks on the roof on the left falling and breaking, the dust rising from the rumpling ground in front of that dumped water. AND the entire background land shifting a couple meters to the right!! The split is right under the farther house, causing it to rotate a little. This is an astounding moment and location to catch on video.
The actual rupture—which caused the shock waves you see swaying the camera—is about 19 kilometers below the surface. The surface effect is dramatic, too, and very similar to the type of fault movement we have in our area: Hayward and San Andreas Faults. Slipping side-to-side rather than forcing up or down means the fault type is called “strike-slip”. The subcategory “transform fault” is used for the one in this film. But it’s another strike-slip like ours. If you want to see the result of similar movement (but not as big) go to the parking lot of the Hayward Plunge and look at the misaligned low walls less than 100 feet east of the parking lot, toward the Ward Creek Trail. They are only offset by a few inches but it’s because of this same type of slip, since those recent walls were built. Some paving in the area is split, too.
Never turn your back on the ocean (or the land, I guess!?) and never turn your mind away from natural systems all around you! They are astounding. And important. [more preaching to the choir]
Joel
————————————
————————————
————————————
————————————
On Tuesday, May 6, 2025 at 12:59:12 PM PDT, 'Joel Pomerantz' via Thinkwalks <think...@googlegroups.com> wrote:
Hello to you!
I invite you to an elevated Thinkwalk this Saturday—or one of the other days listed. Please consider reserving a top-notch spot on high!
We will gather a group three separate times (attend only one) to explore and discuss the water features and hydrodynamics of:
Upper Market Street—Eureka Valley from Ashbury Heights to Kite Hill.
(=) Overview of the city—both literal views and water-wise
(=) Discussion of local historical springs and their status
(=) Walking among the hills with a little up-and-down
RSVP to learn of the meeting spot.
I will ask for a donation at the end, cash or electrozap (digital). Suggested range (pre-adjusted for tariffs and/or poverty) is Zero to $48. Throwing meaningless numbers around is all the rage, I hear.
Sat. May 10 10am to noon-thirty [in the past!]
Sat. May 24 11am to 1:30
Fri. May 30 6pm to 8:30
Pick one! Second choice may also be useful.
In other news: The resource that is arguably most useful for historical research in California is on the ropes.
A withheld-funding emergency has hit our state’s main digital newspaper center, which is at UC Riverside. I use it—the California Digital Newspaper Collection—to search old articles all the time. For some reason, CDNC's state funding disappeared for the present funding period. There was some confusion about next year, but turns out it’s this year’s funding that got yanked. Restoring it and ensuring the future may be a separate matter, but right now:
URGENT!!! This resource will go out of existence if they can’t raise what they need within eight weeks. Contribute what you can at
California Digital Newspaper Collection
cdnc.ucr.edu
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