“Unfortunately, though, the reason the Marina came closest to getting wiped off the map that October afternoon ties directly into the way the Marina put itself onto the map to begin with: artificial fill. The land of the Marina is not natural land at all. It’s a combination of sand and brick and wreckage put in place to recapture some real estate from the Bay. And when it comes to earthquakes, that’s a very bad kind of land to be on.”
A boulder the side of a house balances itself in Vedauwoo, outside of Cheyenne, Wyoming.
This is an awesome example of a precariously balanced rock!
This kind of rock can actually serve as a crude strong-motion paleoseismometer. Basically, it can be assumed that the amount of ground motion required to knock the rock off its pedestal has not occurred in the amount of time that the rock has been precarious like that.
Photogrammetry can be used to make 3D computer models of the rock, and samples can be taken to determine the density. From there, knowing the shape and mass of the rock, calculations can be done to determine the amount and direction of shaking that would be needed to knock it over. Samples of the surface of the rock can be analyzed to determine how long the the rock and its pedestal have been exposed to the sun, which correlates to how long they’ve been out of the ground and precarious. So, you get a length of time and an amount of shaking, and then you can say how long that spot has gone without experiencing that intensity of shaking. That in turn allows you to say something about the earthquake hazard in the area.
Pretty cool, huh? All the more ingenious that someone though to do this just based on seeing a rock perched like it’s about to fall over.
(via twapa)
I am a seismologist with a musical background, and as such, I’ve been compiling as many songs about earthquakes as I can possibly find for the past several years. My criteria for a song to make this list are either that it actually really truly be about earthquakes, or that there be fairly extensive earthquake-related imagery or metaphor. Name-checking specific events or faults gets more points than just saying the word “earthquake” once, even if the song isn’t directly about anything seismic (ie. “Wayward to Hayward” is an instrumental, “Neal’s Fandango” is a pre-1989 song that still mentions Loma Prieta peak a whole lot). The shorter subset playlists I’ve made out of this longer set tend to also include things like “All Shook Up,” “Shakin’ All Over,” “Shake Rattle and Roll,” or “I Feel the Earth Move.” I don’t include those on this list because branching out to include songs that sound seismic in context would be daunting, especially since I am not including every single song I’ve found that actually mentions the word “earthquake” once and only once.
Here is my list as it stands now, in alphabetical order by title. Despite there being many titles in common, each and every one of these is a unique song. None are covers. (Yes, I was surprised to find so many songs called “Loma Prieta”!)
A Quake! A Quake! - The Animaniacs
Another Earthquake - Aaron Carter
The Ballad of San Andreas - Julie Felix
The Burning of Frisco Town - 1906 period song
California - Belinda Carlisle
California Earthquake - Cass Elliott
California Earthquake - Norman Greenbaum
California Earthquake Song - Danney Ball
The California Shake - Margot Guryan
Day After Day (It’s Slippin’ Away) - Shango
Earthquake - Alicia Healey
Earthquake - Fortunate Youth
Earthquake - Little Boots
Earthquake - Sarah Cheevers
The Earthquake - High Country
The Earthquake Came At Dawn - 1906 period song
The Earthquake Of Your Love - Al Kooper
Earthquake Rumble - Bill Nye the Science Guy
Earthquake Song - The Little Girls
Earthquake Song - Ventilator
Earthquake Weather - Beck
End of the World - REM (or Great Big Sea)
La Falla de San Andrés - Kevin Johansen
Getting Through To Her - 311
The Great Alaska Earthquake of 1964 - Bob Blake
Livin’ on the Fault Line - The Doobie Brothers
Loma Prieta - Amy Cook
Loma Prieta - Liz Pappademas
Loma Prieta - Matt the Electrician
Natural Disaster - Muse
Neal’s Fandango - The Doobie Brothers
New Madrid - Uncle Tupelo
Of Pressure - Mirah
Phoenix and the Faultline - The Plastic Constellations
The Quake of ‘89 - Kathy Kallick
Richter Scale - Kent Clark, Elliot Davis, and the Caltech Stock Company
San Andreas - Meg Hutchinson
San Andreas - Steve Gollnick
San Andreas Fault - Anique Granger
San Andreas Fault - Bazza
San Andreas Fault - Lu Watters and the Yerba Buena Jazz Band
San Andreas Fault - Natalie Merchant
San Andreas Fault - The Sundowners
San Andreas Fault - Top Of The Fair
San Francisco, Our Beloved -1906 period song
The Santa Barbara Earthquake - Green Bailey
Shakin’ Shakin’ Shakes - Los Lobos
Sin City - Uncle Tupelo
Southern California Wants To Be Western New York - Dar Williams
Wayward to Hayward - Ricky Skaggs
Why Does This Always Happen To Me - Weird Al Yankovic
Wrecking Ball - Gillian Welch
Any glaring omissions? Any suggestions for expanding this list to an even more insufferable magnitude?
by renowned seismologist Susan Hough:
- Animals sense impending earthquakes: “Every pet owner understands that, say, cats and dogs sometimes behave strangely for no apparent reason; that’s what cats and dogs do. And if an earthquake had not subsequently struck, you can bet we would not be talking about strange animal behavior this week — because we wouldn’t have noticed anything out of the ordinary.”
- The frequency of large-scale earthquakes has spiked: “The number of earthquakes greater than magnitude 7.0 has been somewhat high in recent years but well within the range throughout the 20th century.”
- Small earthquakes are helpful because they release pressure and prevent larger ones: “For each unit increase in magnitude (i.e., going from 5.5 to 6.5), the energy released rises by a factor of about 30. (…) If enough stress has built up on a fault to generate a magnitude-7.0 earthquake, say, it would thus take about 1000 earthquakes with a magnitude of 5.0 to release the equivalent energy. The Earth doesn’t work that way. (…) If there is significant strain energy to be released, it must be released in large earthquakes.”
- “Don’t worry, it was just an aftershock.”: “The implication is that an aftershock is somehow a less worrisome event. Yet, as far as we understand, an aftershock of a certain magnitude is no different from an independent temblor of a similar magnitude. The shaking and rupture are the same; the energy released is the same. And aftershocks can be more damaging than larger “mainshocks” if they strike closer to population centers.”
- Earthquakes are a West Coast problem: “As millions of people on the East Coast were just reminded, less active does not mean inactive. By the end of the 19th century, two of the most notable temblors in the United States were the 1886 quake in Charleston, S.C., and a sequence of large events centered near the boot-heel along the New Madrid Fault of Missouri in 1811-1812. We don’t know exactly when or where the next Big One will hit the United States, but the central and eastern United States will inevitably experience large quakes in the future. (…) You have been warned.”
A 3-D view of the surface rupture of the April 4, 2010, El Mayor–Cucapah Earthquake (red line) reveals a new fault line connecting the Gulf of California with the Elsinore fault, which is likely to become the main fault at the boundary between the Pacific and the North America plates. Credit: Caltech’s Tectonics Observatory. (via Caltech)
Complex and bizarre fault geometry for the win!
(Though I’m surprised about this “Superficial Simplicity” part of the title of the Nature Geoscience paper. The mapped surface rupture from this event is a mess!)
Julian. 28. Riverside. Seismology PhD student. Player of many musical instruments. Occasional camera wielder. Personifies places and things and draws comics about them. My heart is in San Francisco.
