> this feature and the sounds of its vibration are sacred to Native American Tribes of the four corners region, and they ask that you listen and share with according respect.
Does anyone happen to know if this means they were actually hearing these vibrations in some way? (Only 25 times slower and less audible)
There were the lunkheads a few years back to pushed over a rock formation at another Utah park so as obvious as showing respect might seem, adding a reminder might get a few more people into the proper state of mind instead of thinking they're at Disneyland.
When you visit this arch, there are many signs telling you to treat it with respect as the natives do. They probably just got permission from the tribe to do the recording with the caveat that they treat the arch with similar respect.
It's an incredible arch, but one of the harder ones to get to.
It used to be easy to get to. Lake Powell came within a quarter mile of it when I was a kid. When it hit full pool, I think the lake actually extended under the arch.
At that time, nobody was particularly concerned with Native American sentiments about the arch. I mean, we didn't do anything that was obviously disrespectful to us, but I don't know how the Native Americans felt about us just walking up to and under it.
(And, technically, it's a bridge instead of an arch, since it goes across the watercourse.)
I find it one of the more amazing things, that so much of our physical world has a time/frequency dimension.
And our bodies have at least a couple of obvious senses (vision and hearing) to experience some frequency ranges. And with modern computing power, many natural phenomena on our planet and across the universe can be morphed into ranges we can see or hear.
And this in turn not only aids in scientific understanding, but also allows (some of) us to respond emotionally.
And that keeps me awestruck, even when other properties of our species can be utterly depressing.
You reminded me of this scene from Battlestar Galactica that has stuck with me since I watched it (spoiler alert). Conversely, the character laments the sensory limitations of the human body :)
This is wonderful! I can't help but to be reminded of the book (and excellent movie) The Hunt For Red October, where a [edit] "caterpillar" drive on The Red October sounds like seismic activity, but when sped up is clearly mechanical. This is not he same, I know, but it has the same vibe.
It's similar to what the astronomy people do with the data from probes floating in space collect [0]. They keep trying to find ways to make the data interesting as opposed to just numbers in a spreadsheet.
Following links at the bottom of the submitted page, there is a tonne of information on how this data was collected. There are animations of the different ways the rocks move due to the vibration.[0] I'm assuming the visuals are exaggerated, but that's just my uneducated on the subject mindset of rocks don't move like that.
The pure science/learning/hold my beer/etc aspect of this is pretty awesome.
I worked on a seismic monitoring system for civil engineering structures. We recorded data at 200 Hz (though all the interesting content is in the zero to 15 Hz range). Once I tried this experiment with some of the data from a bridge in a harbor. It was very cool, you could hear so much going on in the bridge.
Ambient seismic vibration is something of a hidden world around use. With a very sensitive accelerometer you can measure the shaking in a concrete pad due to cars a block a way. Looking in the frequency domain things like when rush hour is and which day is the weekend pop out like a sore thumb.
In between the acceptance of electronic intelligence and the dawn of everything being computer based, spooks spent a lot of time inventing ways to get this kind of info from dumb sensor data.
At one point MI5 could apparently lift crypto keys from the noise of the cipher machine through a wall. Obviously being MI5 this was to spy on the French and not the Russians, but still.
Also depending on the scale, seismic surveys are seriously affected by nearby roads and construction, where "nearby" can mean several km in some cases.
Song of Sand by Suzanne Vega
If sand waves were sound waves
What song would be in the air now
What stinging tune
Could split this endless noon
And make the sky swell with rain
If war were a game that a man or a child
Could think of winning
What kind of rule
Can overthrow a fool
And leave the land with no stain
https://www.youtube.com/watch?v=KzNyao--tuY
Video magnification -- I've always been surprised that this hasn't been commercialised. Would be valuable in e.g. infant monitors, or as a diagnostic tool in remote video medical consultations.
Strange there isn't a page for the Delicate Arch. That's got to be the most iconic arch in Utah. Very interesting project though! I think my favorite is the Rainbow Arch (not bridge). If you click through the links to Sketchfab there are 3D scans of the arches to get a better view than the pictures provide.
Also, I highly recommend seeing the Arches and other landmarks in Southern Utah if you have the chance. Some of my favorite places on this planet.
I long time ago I had an audio cassette of recordings from, I think it was Voyager, of the ambient interplanetary EM signals it encountered transposed somehow into audio. It was eerie and wonderful, a little like whalesong, and one of the most haunting and beautiful things I've ever heard.
Is there a name for shifting the recorded phenomena into the part of spectrum where humans can directly sense it? Or for converting signals into different medium, so that we can hear or see signals that we couldn't sense otherwise? I'd like to know the name so that I can hunt for more examples and applications.
A good example is Dwingeloo radio telescope where they convert pulsar signals into audio in realtime so that you can listen to it using headphones. Another example is playing a sound every time your runtime preforms garbage collection, to gain first-hand intuition for internal operation (like you can pick up any abnormalities in the car engine sound).
I think this is simply using one rate for sampling and another for playback.
Another comment suggests seismic samples like these are taken at 200 Hz. That is comfortably above the rock vibration frequencies of a few Hz. If one simply plays back these samples 100x faster the result would appear as 20 kHz sampling and the signal power that was originally around a few Hz would be heard at a few 100 Hz. The audio sounds a bit higher in frequency so perhaps these numbers are not precisely what were actually used but they give the idea.
That's just the shifting. Accelerometers are used for the original sampling so there must also be some sort of pre-processing in the original sampling domain (the example 200 Hz time base) to convert acceleration information into displacement. This is a 3D displacement so then some other transform must be applied to represent the 3D vibrations with a 1D model.
It's worth renting an SUV in SLC and some camping gear from REI on the way to arches, and driving through to Denver, dropping off the gear at REI and going home on the plane. You could probably even get some skiing in at Arapahoe Basin.
> this feature and the sounds of its vibration are sacred to Native American Tribes of the four corners region, and they ask that you listen and share with according respect.
Does anyone happen to know if this means they were actually hearing these vibrations in some way? (Only 25 times slower and less audible)
[0] https://geohazards.earth.utah.edu/tones/RainbowBridge.html