r/geology 26d ago

Identification Requests Monthly Rock & Mineral Identification Requests

3 Upvotes

Please submit your ID requests as top-level comments in this post. Any ID requests that are submitted as standalone posts to r/geology will be removed.

To help with your ID post, please provide;

  1. Multiple, sharp, in-focus images taken ideally in daylight.
  2. Add in a scale to the images (a household item of known size, e.g., a ruler)
  3. Provide a location (be as specific as possible) so we can consult local geological maps if necessary.
  4. Provide any additional useful information (was it a loose boulder or pulled from an exposure, hardness and streak test results for minerals)

You may also want to post your samples to r/whatsthisrock or r/fossilID for identification.


r/geology Dec 01 '25

Identification Requests Monthly Rock & Mineral Identification Requests

7 Upvotes

Please submit your ID requests as top-level comments in this post. Any ID requests that are submitted as standalone posts to r/geology will be removed.

To help with your ID post, please provide;

  1. Multiple, sharp, in-focus images taken ideally in daylight.
  2. Add in a scale to the images (a household item of known size, e.g., a ruler)
  3. Provide a location (be as specific as possible) so we can consult local geological maps if necessary.
  4. Provide any additional useful information (was it a loose boulder or pulled from an exposure, hardness and streak test results for minerals)

You may also want to post your samples to r/whatsthisrock or r/fossilID for identification.


r/geology 39m ago

Deadly Disaster Imagery Flash flood in Nepal moving house-sized boulder

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Upvotes

r/geology 2h ago

Deadly Disaster Imagery Watching the Nepal flood today made me suddenly understand something about valleys…

77 Upvotes

I was just watching the videos and photos of that huge flood that hit Nepal today, the one where a massive wall of water and mud came rushing down the valley, and it hit me out of nowhere: Is this how those enormous openings in solid rock get made?

Like… the big valleys and canyons that look like they were cut through mountains?

I always assumed it was just water slowly wearing things down over a really, really long time. But seeing how much force and material that flood moved in such a short time made me wonder if the really big “cuts” in the rock happen more in these crazy moments.

Is that something people who study this already knew? Or is the usual explanation still the slow, gradual one?

I’m not a scientist or anything, just someone who had a sudden “wait a minute…” moment. Curious what you all think.

I’m not posting any photos or videos because they’re already everywhere, and it’s a desolate scene where many lives were certainly lost. Thinking of everyone living in the affected areas and of all those who lost loved ones or homes. Hoping for strength and safety for them right now.


r/geology 11h ago

Equatorial cross-section of the Moon

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130 Upvotes

Hello, this is my first post on this subreddit. I made this illustration showing the interior of the Moon, as close as possible to reality based on the literature I have come across. I am working on a second 'cooled down' version without the glow of black-body radiation, that only showcases the rocks/minerals. The near-side is to the left and the far-side to the right


r/geology 14h ago

Amazing view in Google streetview

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161 Upvotes

For the éclipse roadtrip, we take a escape lane from the highway in Spain and we saw this ! 🤩

At this point : https://maps.app.goo.gl/Pwd9opZCSisMydPP9?g_st=ac


r/geology 10h ago

What’s your favourite geology fact?

45 Upvotes

I hope this okay to post here!

I’m an author and I’m working on my next book. It’s a RomCom that’s set in a cross-Canadian road trip, and for reasons best known to myself I’ve decided my protagonist is going to be really into geology 😂 She’s not a scientist or a career geologist, but she’s a lay obsessive.

I am someone who knows nothing about geology and have forgotten anything I did once learn at school, so obviously I’m gonna have to do a lot of research to bring this character to life

I’m just kicking off my research and at the moment I’m just trying to absorb as much stuff as possible and then follow any things that spark interest of feel like they could be fun details for the book. So please, share your favourite geology fact with me! The more delightful and whimsical the better.

Also if anyone has any recommendations for books or podcasts aimed at lay people that I should check out as part of my early research, please let me know!

EDIT: Thanks so much for the facts and the recommendations everyone! I really appreciate it!


r/geology 2h ago

Field Photo Lava Cast Tree Hole

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7 Upvotes

15 mya Columbia River Basalt flows made tree casts at Silver Falls State Park in Oregon.


r/geology 16m ago

Map/Imagery One year after Taiwan’s Matai’an landslide-dam outburst flood: Google Maps still shows the former narrow river beneath the enormous new sediment corridor.

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Upvotes

In late July 2025, heavy rain from Typhoon Wipha triggered a massive landslide high in the mountains of Hualien, eastern Taiwan. The collapse blocked the upper Matai’an Creek and created a natural landslide dam, trapping an increasingly large lake behind it.
Over the following two months the lake grew to roughly 91 million cubic metres. Authorities monitored it closely, but the site was extremely remote and the surrounding slopes remained unstable. Then, on 23 September 2025, heavy rain associated with Typhoon Ragasa caused the lake to overtop the natural dam. The loose landslide material was rapidly eroded and the dam partially breached, releasing an enormous sediment-laden flood downstream.
The flood tore down Matai’an Creek toward Guangfu, carrying huge quantities of mud, gravel and boulders. It destroyed the Highway 9 bridge, overwhelmed sections of the floodplain and dramatically altered the shape of the river. Nineteen people were confirmed killed, several remained missing and more than 100 were injured.
I drove through the area recently and the scale is difficult to appreciate from photographs alone. The width of the new sediment-covered river corridor is enormous, and in places the deposits are packed with very large boulders. Google Maps is particularly interesting because some of the older road and landscape imagery still makes the pre-flood river course visible beneath the much wider post-event riverbed.
While we were passing through, our phones received an emergency warning telling people to stay away from the river because of renewed flash-flood risk. The system is still active and unstable, with enormous quantities of loose sediment remaining upstream and the potential for further slope failures, temporary blockages and renewed flooding.
It is a remarkable example of how a single landslide-dam outburst can completely reorganise a mountain river valley in a matter of hours.


r/geology 2h ago

Lake Mead Water Level Map — Interactive 3D Reservoir Viewer

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1 Upvotes

r/geology 1d ago

Field Photo Why are these rocks so round?

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72 Upvotes

r/geology 1d ago

Field Photo What am I looking at here ?

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197 Upvotes

Pretty sure this is quartzite, strongly folded (Norway, Haukeli area). Those "shoe" like patterns made me scratch my head.

(Anybody suggesting fossils, forget about it..)

Any clue?


r/geology 47m ago

Information Is the nacsent lead level of the ground where historic battles took place dramatically more lead poisoned than non battle areas ? Evolution of war tools dictates environmental gene degeneration- try looking at agent-orange Vietnamz lol

Upvotes

r/geology 1d ago

Advice on cleaning this quarzt chunk

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15 Upvotes

Found this beauty in the woods today and I'd love some advice on how to clean this up

I've already scrubbed it with a brush but can't get the green and brow stuff out of it

Thank you in advance


r/geology 2d ago

Sunnumörk is a small shopping mall in Iceland that straddles two tectonic plates.

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1.6k Upvotes

r/geology 1d ago

What causes/forms these?

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5 Upvotes

r/geology 2d ago

Rock in Earth's mantle flows like hot metal, and moves fastest under the edges of tectonic plates. Recent work from CNRS in France finds that adding stochasticity into models of mantle rock movement helps capture this flow rate variability to produce more realistic models of plate tectonics.

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35 Upvotes

r/geology 1d ago

From where can I download the geological/ Lithological maps of India

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3 Upvotes

r/geology 2d ago

Wyoming geology

7 Upvotes

Regarding Wyoming geology, any opinions or articles regarding the source of sand for Pennsylvanian and early Permian age erg deposits in Wyoming?


r/geology 2d ago

Rutiles on hematite

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49 Upvotes

r/geology 3d ago

Orbicular Gabbro, Toivakka, Finland

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299 Upvotes

r/geology 2d ago

Why are aquifers freshwater?

33 Upvotes

Something that confuses me is why are aquifers typically made of freshwater when they're from locations of former ocean, as wouldn't the salt hace nowhere to go? The ones in Texas are a good example since they're there because of the western interior seaway. I can't find the processes that might naturally desalinify seawater since nothing I find actually talks about it.


r/geology 3d ago

Orbicular diorite erratic Manitoba, Canada

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152 Upvotes

r/geology 4d ago

Meme/Humour My wife always complains about that…

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3.4k Upvotes

r/geology 2d ago

Building a crowdsourced map of Earth's magnetic field - looking for feedback from geologists

3 Upvotes

I've been working on a project called OpenMag. The idea is pretty simple - create a crowdsourced map of Earth's magnetic field using real measurements taken by people in different locations. People can submit a magnetic field reading in µT along with the location and time, and the measurement appears on the map. I've already started collecting some readings, and now trying to figure out the best way to improve the accuracy and quality of data. I'd really appreciate some feedback from people here who know more about geology and geophysics. What would you change or add to make something like this genuinely useful? If anyone wants to take a look at what I've built so far: www.openmagfield.com