Wednesday, June 6, 2012

A Wednesday Whatsit: What is it?

A pair of puzzles for a Wednesday afternoon. What are these???

Location is on the Colorado Plateau, southwestern part; the top photo is about three feet across, while the bottom photo is 3-4 feet across...
First prize is bragging rights!
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8 comments:

  1. Ron SchottJune 6, 2012 at 12:41 PM

    #1: Boxwork type veins (from a concretion?)

    #2: Tool marks (trace fossil on a sandy(?) substrate.

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  2. LockwoodJune 6, 2012 at 12:42 PM

    Upper one look like inverted cast of mudcracks- sand infills cracks, and after lithifcation, withstands weathering better than underlying mudstone. Lower one less certain about, but looks like some kind of drag marks. Amphibian/reptile tail(s)?

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  3. Callan BentleyJune 6, 2012 at 12:42 PM

    First one is cast of dino footprint in mudcracked mud, with the cracks radiating out from the footprint like a spider web, indicating the footprint came first or contemporaneously with the stresses that caused the mud to crack. Not sure about the second one...

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  4. Elizabeth RJune 6, 2012 at 1:40 PM

    The first is inverted mudcracks. The second are swimming tracks from a dinosaur.

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  5. Randy A.June 6, 2012 at 2:02 PM

    I agree with Ron Schott...

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  6. blog with no nameJune 6, 2012 at 5:29 PM

    Top one looks like "worm burrows" in the Kaibab Limestone.

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  7. megJune 6, 2012 at 5:57 PM

    1. I agree with Callan, I didn't notice the footprint until he pointed that out.

    2. Trace fossil? Maybe feeding traces (like from a trilobite?)

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  8. biobabblerJune 7, 2012 at 9:05 AM

    I have to say I really don't know, but these photographs are MOST delightful to contemplate. Imagination (esp. since I am a geology ignoramus) is a fun muscle to exercise. That 1st one (ignoring all the erudite guesses your blog visitors have posted) is a TOTAL mind bender!

    The 2nd looks a bit like BIG ol' leaves, but guessing from above comments, not likely. =)

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