r/geology • u/seapube • 2d ago

What would the formations under the bridge be called?

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50 Upvotes

95% Upvoted

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31

u/Accomplished_Soup496 2d ago

IDK anything about this cave or the local geology but those features on the "square" blocks beneath the bridge are flute casts. Formed from scouring at the base of an ancient stream and backfilled with more sediment.

3

u/wenocixem 2d ago

what they say….

are they falling of the bottom of the floor upon which they sit or from the roof

1

u/Accomplished_Soup496 1d ago

The "breccia" that people are referring to means that the local blocks of rock broke away and were encased in much younger cave deposits, likely a mix of carbonate minerals.

1

u/stain_XTRA 2d ago

shi maybe it is dropstones

11

u/Siccar_Point lapsed geologist 2d ago

This is a cave collapse breccia, still within the cave. Very cool!

6

u/snakepliskinLA 2d ago

I could be wrong, but I would call it breccia.

11

u/The_pizzacutter 2d ago

In the caving world we just call that breakdown. It’s just stuff that fell from the ceiling/walls. If it was relithified it would be called solutional collapse breccia

1

u/HorikLocawudu 2d ago

That's the term I couldn't remember.

0

u/stain_XTRA 2d ago

Dropstones maybe? but that’s for rocks that sunk into sediment so I feel like it’s wrong

0

u/gertbfrobe22 2d ago

Breakdown blocks

-2

u/BucsLFC420 2d ago

Rocks in formation