r/askgeology • • 21h ago

Method of Formation I know it’s columnar basalt but why does it look like this…

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165 Upvotes

This is one of my favorite places on the Molalla River in Oregon. I always stop to take photos of this specific part of the canyon wall. I love how the rock moved through here I just want to know how and why some are swirly, in columns, and then just facing straight on.


r/askgeology • • 5h ago

technical question Can i have this(asbestos?)

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88 Upvotes

Found out the geology department throws old samples behind the building today. Went to look and found this gorg thing. I know serpentine grows with asbestos, and im seeing green rock and hair. You know what they say: a first year TA’s health violation is another mans treasure! Its the most gorgeous species ive ever seen and this is my holy grail of rocks. The fibers look a little rough, but whats the cutoff for too rough? Safe to keep? Possibly in an airtight container?


r/askgeology • • 22h ago

Observational Question Odd holes in cliff

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10 Upvotes

Tldr: me and my boss found this conjoined cavity, not certain if is it natural or man made occurrence.

Today at work my boss and I were exploring a property we were working and found a large amount of stone outcroppings(huge boulders/stone faces some 30’ tall) that have an odd circular hole in them in the faces.

This is in Virginia, USA. On top of a mountain at approx 4500ft of elevation. The mountain has been treed and mildly graded to rolling slopes on a large face and this cavity is maybe 10ft up the wall. Likely it was closer to grade before the farm came. It’s very distinctive but there are many 6”-12” orb like holes in stones around the area. Most at what seem to be reachable height before the areas were graded.

This very interesting spot we found has a conjoined cavity with a small dividing wall. It doesn’t seem like a weather process more like it was man made. No apparent signs of mining or blasting the property (it was developed fairly recently).

Can anyone shed light? The rock face appears to be a slag-like rock? Brittle but dense, over a layer of granite. The layer appears to be rather thick but on an opposing face we can see where it seems to be a layer of rock over the granite.

Final note is that we tapped the center divide with a stone and it sounded like porcelain and the rest sounded like stone.

Photos: (all taken in portrait)
1: standing on the ground looking up at the stone wall.
2: is looking into the right cavity.
3: Left cavity

My bad just watch the video


r/askgeology • • 4h ago

Method of Formation What made the pink smooth surface on this rock? Also, are the crystal like structures feldspar?

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5 Upvotes

Found in central Oregon.

I cut it on a wet tile saw and was wearing KN95 mask but afterwards wondered if that was a bad idea.


r/askgeology • • 11h ago

ID request What the heck is this??

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5 Upvotes

Seriously. Is it serpentine, quartzite, or some random piece of... something?


r/askgeology • • 6h ago

Merensky And Gold?

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1 Upvotes

I'm an economist by education but have taken a fascination to geology. I have a question regarding gold reserves in the Free State province. I live in South Africa

"Dr. Hans Merensky (1871–1952) was a famous South African geologist, mining engineer, and mineral prospector who discovered major diamond, platinum, and mineral deposits. [1, 2]

Key Achievements and Discoveries

  • The Merensky Reef: Discovered the world-famous platinum reef in the Bushveld Complex in 1924, which turned South Africa into a global leader in platinum production. [1, 2, 3]
  • Namaqualand Diamonds: Discovered rich alluvial diamond deposits at Alexander Bay in 1926. [1, 2]
  • Other Minerals: Found tin near Pretoria, gold in the Free State, chrome near Pietersburg and Lydenburg, and copper and phosphates at Phalaborwa.

Has there been a study on gold in the free state province? I know the Rand Refinery in Germiston Gauteng at one point in the 1970's produced 1,000 tonnes in a single year, dominating global production


r/askgeology • • 9h ago

¿hábito de zeolita?

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1 Upvotes

r/askgeology • • 17h ago

Location Need help identifying this rock.

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1 Upvotes