#proterozoic

[whats-in-a-sentence]

A unified geologic time scale

"The Moon: A History for the Future" - Oliver Morton

[geologyjohnson]

Weird Precambrian Microfossils

Here is one of the weird fossils I've been working on since getting back to Belgium. It's about 60 microns long, or 0.06 millimetres and 1.4 billion years old and no one in the lab has seen anything like it before. The texture is not just a surface pattern, the light areas are pits, the dark areas are raised tubes. There are multiple layers of tissue and structures that look like pore that could open and close. These features indicate the fossil is probably from a eukaryotic organism - those with complex nucleated cells. I don't think this level of detail has ever been preserved in a fossil this old before. Additionally, you normally need to look at rocks less than a billion years old to find fossils with this level of complexity.

This fossil is significant because it lived at a time when we did not think life this complex existed yet. This is a period of time called "The Boring Billion" where the Earths environment and biology were thought to have entered a period of stasis - e.g. nothing changed for a billion years. My work will join a growing body of research that shows this interval was anything but boring, and was actually a pivotal period in the development of our planet and the life that inhabits it.

[goodrichthyseskdalensis]

People who think Dinosaurs is super controversial have never experienced the horror of debating the biological origin of early Precambrian supposed fossils.

[joemomrgneissguy]

Xkcd

[galswintha]

It's official! Skalickie Skałki (Skalice Rocks) confirmed as the oldest rock outcrop in entire Poland. Made of sillimanite gneisses they were said to be even a billion years old, but current estimations are closer to 600 mln yrs.

[redelk10]

I’m a bit of a rock collector. I don’t buy rocks, but whenever I go somewhere I always make sure to grab an interesting rock. Out of all my rocks, literally across the world, this is now my favorite and I found it in a local creek.

This is iron striated jasper, also known as banded iron formation (BIF). This rock was created 2.5 billion years ago as early photosynthetic bacteria repeatedly saturated the atmosphere with oxygen. When the atmosphere was saturated, iron in the oceans would rust and sink to the bottom (the black bands). Every time the atmosphere filled with oxygen, the bacteria that created it would choke themselves out and die back to near extinction. As the Earth slowly returned to normal oxygen levels, the rust would get covered with sediment. This rock is a timeline of the “boring billion” as life struggled to achieve equilibrium.

That’s pretty cool, right? This was already a bucket list rock because of that, but what’s even cooler about this specific rock and the reason why it’s now my favorite is where it was found- Cedar Rapids, Iowa (yes, kinda doxxing myself here).

While doing a creek walk for my behavioral ecology lab, I found this rock in Indian Creek. What’s weird about that is the closest banded iron formation is in Minnesota by Lake Superior. Specifically the Cuyuna Ranges almost 400 miles away.

How did a rock produced 2.5 billion years ago, 400 miles away get here? Glaciers. Most likely, the preillinoisian glacier 1,800,000 to 500,000 years ago. This glacier dug out this rock, dragged it from Minnesota to central Iowa and deposited it here.

Then, it was likely pretty recently, within the last 100 years, that this rock, a physical representation of an early biological struggle so intense it repeatedly altered the Earth significantly (and a type of rock that only exists on Earth, was only produced by biological means, and will never be produced again), was then exposed by the current of Indian Creek, pulled some distance by the current, and then found by a college student who just happens to be enough of a nerd to care about it.

I feel like my words don't do this rock justice, but this small, unassuming rock is profoundly impactful to me because of how it was created and what it took to get to where I found it.

[imposterfish]

Avalon Explosion but on the surface lol (theres two charnia that were washed up) (I drew this so much faster cause my bf gave me a drawing pen thing too)

[phoronopsis]

Starting a new conspiracy theory that aliens did visit Earth but it was like 2 billion years ago in the middle of the Proterozoic. They were like "holy shit look at all this ALGAE" and made a little research base and then after a few decades they ran out of funding and left. Everything they built was destroyed by billions of years of geological activity; they didn't seed Earth or anything cuz our microbial ecosystems were already established and everything; they left no detectable trace and we'll never know they existed (except for me cuz I'm built different 😎)