Uh what? I mean we can get geochemistry and look for trace elements.
Paleontologists will absolutely look for fossils in sand, they do it all the time. I just sent off a bunch of sand and clay for pollen analysis and I’m not sure how they process it but I know it involves dissolving inorganic material in acid sometimes.
Most of the time no one looks at sand in bulk. It’s…you can imagine, a daunting task. Sometimes people (individuals) will look at sand for some diagnostic purposes - usually in my line of work to note the type and abundance of minerals present, or especially the distribution of particle size and clay/silt content. I know other fields will survey things like diatoms and foraminifera for paleontology but also for I think oil exploration because indicator fossils are important but I don’t do that so I’m not really sure I can speak more to it.
A lot of time people look at sand in the field with a hand lens or drag it back to the lab to look at it with a basic microscope. Or slap it in epoxy and make a thin section. Sending it off for geochemistry is…possible but may not be especially illuminating depending on what you’re trying to learn. People can also date the sand using optically stimulated luminescence (OSL) to get a date of when the sand was last exposed to sunlight (and thus, deposited) if the sand is in the right age bracket (<150ka ish).
Rarely people get more involved with things like XRD/XRF, SEM, microprobe uh… something else, I’m sure. That’s more of a straight academia realm though.
I went off on a tangent but people slap sand in machines and other things to find out stuff all the time.
Note: Only some types of sand from some places have an interesting appearance microscopically. Most sand will just look like little rocks. Or at least that iirc from the last time this image was circulating.
Oops, indeed, updated title from “Sand is beautiful under a microscope” since that wasn’t totally accurate. “Oops” because I had in fact suspected as much!
Is this real? I feel like some of the details on these things in the pictures look very macro. Like the colored striations on the shell pieces. Super cool if it is, but I’m not so sure…
Having looked at sand under a microscope for many, many hours: kinda? These images are not just heavily curated but arranged. Yes I’ve had a bunch with random shell fragments and forams SOMETIMES but notice in those images the pieces are carefully spread out?
Most clean sand looks like the bottom right two images but even those are already filtered for interest. I have a bunch of stuff that looks like the bottom middle photo, which is a contentinal glacial sand deposit that is sorted by wave action to have more heavy minerals (pink garnet, black probably magnetite, a splash of green epidote and white qtz splashed in there). It’s usually a thin THIN layer found on some beaches. It’s like a “pretty” sand people know about and not indicative of the vast majority of sand.
Most sand even in a variety of environments is quartz and random lithic (rock) fragments.
I get a little annoyed when these images (usually the top 3) are shared and layman say, “look at how beautiful ALL sand looks! Appreciate the micro world blah blah some inspirational quote.” It’s straight up misinformation but because it’s “just sand” most people don’t care.
I care. Regular sand IS pretty and it’s neat to look at for a little bit. Stop making sand feel bad with unrealistic beauty standards :p.
This made me laugh but I can see why if you have interest you’d be somewhat annoyed by arranged and selected items. It’s not a natural sample. Sand’s not the only thing I’ve seen this done with. There are worse things in the world to be fussed up about tho’. And I do like the heart shaped piece 💜
But I did find this image of the garnet sand that would be a good example of the bottom middle picture in the post. You can make out the pink, black, and green zones and I think it looks rad.
I always think sand is worth looking at at least once, lol. Get a hand lens (like $10?) and check it out!
Also it’s probably pink not because of garnet but because of the oxidized bedrock. I’ve seen a ton of stuff that looked like that on the shores around the Lake Superior and it was usually some form of basalt, rhyolite, or rare sedimentary interbed. You’d probably see a bunch of smaller reddish pinkish sand grains along with darker gray ones and maybe some milky quartz. But IIRC Canadian Shield stuff is pretty diverse and I recall there being some gnarly meta stuff out there so you might find some glittery mica and garnets.
Do you know what the sand from elafonissi beach (Crete) looks like under a microscope? It really does look pinky when you’re there, and I was told it was because of a certain type of seashell that made up the majority of the top sand. I was a kid though, definitely could have been lies.
Never heard of it but sounds nice! Pink sands can happen for a variety of reasons and I’m not sure exactly what is going on in Crete. I collected some pink sand in the Bahamas that I found interesting and long story short, it was manganese stained fossil coral. It sounds like a similar process is happening in Crete with red stained foraminifera tests (tiny shells). Not sure what the red is in the tests in Crete without digging into it as I only did a cursory search but iron oxide and/or manganese aren’t horrible guesses.
Whoa you were not kidding about that being pink. Holy cow. I mean…the pink grains could potentially be garnet but I’m a little doubtful and unsteady at saying that for sure. They have conchoidal fracture and a vitreous sheen which could easily be quartz, perhaps stained by something else going on in the area (Mn? > Fe).
Those blue green grains are fricken neato, I don’t have a good explanation for them and can’t really get a good look from the photos.
I see a couple of green grains that could be epidote or some other green mineral, and one that looks a little olivine-esque but it’s hard to tell.
It’s one of those things that you poke and prod and rotate and stare at for a while before giving a broad, hand wavy guess.
It would probably be helpful to look up the location and the formation to get a better sense of what to expect.
Probably some combination of electromagnetic effects in that specific section. Happens to oscillate just right. Though these weights can be used for wind issues, I’m seeing a lot of references to dampening other kinds of vibrations. Might help you find a better answer.
Hmm. It’s odd that this isn’t ALWAYS vibrating, but it IS only between these two poles that I’ve noticed the vibration. But why not between other sets of poles? And since the cable vibrating the most isn’t a power cable (I believe it’s fiber, but it could be copper - but it’s definitely telecom, since it’s not insulated on the top crossbar, as the other power cables are), it can’t really be much power going through it. I’m kind of hoping someone else has seen similar behavior somewhere else. You can see the anti-wind-twist devices (don’t know what else to call them) bolted to the other telecom cable (sort of diamond-shaped) and they will cause the cable to stabilize when the wind is really blowing, but you can see the wind isn’t blowing at all, and the cable continues to vibrate quite noticeably. I really do hope someone else has seen something like it elsewhere…
In regards to it only being between those two poles, I’d wager it simply comes down to tension. The other cables are tensioned correctly and this section is either too loose or intentionally loose as some sort of expansion/contraction relief.
This is indeed very interesting. I can reccomend asking the telecom company that owns the line with a quick email as to whats going on here, they usually like to answer such questions. Maybe post in a sub thats more familiar with mechanics/electronics or even general asklemmy?
Did you measure the distance between the poles? I suspect it’s different from all the other spans, so this one happens to have a resonant frequency that exactly matches whatever vibration source is already there (could be the tension too). As for sources of vibration, wind is probably it, even if it’s not strong. If it just happens to create the right frequency, the cable will vibrate just like a violin string.
I immediately thought of the original Tacoma Narrows Bridge, which collapsed after wind caused a resonance to build up and literally shook itself apart: en.wikipedia.org/…/Tacoma_Narrows_Bridge_(1940)
No, I’ve never tried to quantify the variables in that way. Just out walking the dog, and notice this strange behavior from time to time. I always assumed the poles were placed a specific distance apart, but honestly, I’m not sure. I suppose if I ever have the urge to pace it out to get a good estimate, I will…
For what it’s worth: I counted about 85 or 86 “clicks” in 10 seconds. It’s a loud click followed by a quieter click, like as if it’s oscillating towards and away from you. The sound of the click itself is loudest at about 2.6 khz - whether that is simply the sound of friction, or some sort of electrical phenomenon, I don’t know.
The fuzzy area at the bottom half of the spectrogram is the dull roar of distant wind. The clicks themselves show up as spikes, and the intense colors on the right are from where the voice starts speaking. The dark band above 10K is just the data lost from audio compression.
Well, I can say definitively that I know what is making that clicking sound. It’s hard to see since the cable is in silhouette, but there are silver-colored spirals wound around the cable, and the sound is made by the plastic sheathing of the black cable wobbling inside of those metal spirals. The spirals are made of aluminum, I’m pretty sure. Those spirals are put there to stiffen the the hanging cable, and appear on the hanging cable between every set of poles (not just these, that are wiggling). There are two spirals mounted on each cable between the poles. I assume the spirals are mounted there to provide damping, just in case the wind does cause the cable hanging between the poles to swing too much. But, there was no wind blowing when I shot this video (Dec 5, 2023). The voice you hear is mine, just speculating on what might be causing the oscillating cable…
mildlyinteresting
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