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> And then there’s all that plastic. Studies have shown that increasing amounts of plastic “marine litter” are being deposited on the seafloor everywhere from c
by alquemist 6y ago
> And then there’s all that plastic. Studies have shown that increasing amounts of plastic “marine litter” are being deposited on the seafloor everywhere from coastal areas to deep basins, and even in the Arctic. Wind, sun, and waves grind down large-scale plastic artifacts, leaving the seas full of microscopic plastic particles that will eventually rain down on the ocean floor, creating a layer that could persist for geological timescales.
Sandstones. Sandstones originate as far as hundreds of million years in the past. Occasionally they harbor fossils, which are indeed rare. But a lot of sandstone is made of sanded up organic material which we can readily identify, even if we can't point to the specific organism they originated from. We only need a tiny industrial-related grain of sand (ceramic, glass, metal, plastic traces) to point to a past civilization. Nobody ever noticed such a grain of sand.
- phreeza 6y agoThey we would not have access to petroleum, so no plastic.
- c22 6y agoSure, and the article mentions other possible signs of civilization as well, then it goes on to say: > So it might take both dedicated and novel detection methods to find evidence of a truly short-lived event in ancient sediments. In other words, if you’re not explicitly looking for it, you might not see it. That recognition was, perhaps, the most concrete conclusion of our study. I'm not bullish on pre-historic civilization, and neither is the article, but the takeaway is we may not have reason to expect that we'd have found these tiny industrialized traces without a search aimed specifically at them. As far as I know, such searches have not been carried out in earnest to date.
- alquemist 6y agoWe've put old rocks under the electronic microscope. That's how we identified billion year old cyanobacteria fossils. While there is no readily available comprehensive record of who searched for microfossils by looking at what old rocks, with or without a microscope, it's not like it's a new idea. https://ucmp.berkeley.edu/bacteria/cyanofr.html https://ucmp.berkeley.edu/bacteria/cyanofr.html
- c22 6y agoI feel like we're talking past each other here. The very first sentence of your link says "The cyanobacteria have an extensive fossil record." In the next paragraph it says "Cyanobacteria are among the easiest microfossils to recognize. Morphologies in the group have remained much the same for billions of years..." So not a truly short-lived event in ancient sediments then.