Friday Rock Blogging: Mud

i-306fbb3155755cf0d7cecb755827bff8-mud-ridges.jpg
Picture courtesy reader Martin. Or maybe Martin doesn't actually read this blog, and it's just Wren. Anyway, thanks, Wren and Martin!

Today's rock is a geopuzzle: What's up with these ridges? How did they get there, and what determines their size?

I don't actually know the answer, so this is the best hint you're going to get out of me.

More like this

Every so often on Cognitive Daily, someone will post a comment asking for help on a paper they're writing for school. It's pretty clear where these people come from: they've done a Google search on video games or whatever it is that interests them, and our post is the first thing they've found that…
This time around, we're talking to Mark Chu-Carroll of Good Math/Bad Math. What's your name? Mark Chu-Carroll What do you do when you're not blogging? Chase my children around.... (I've got a 6 year-old girl and a 3 1/2 year-old boy.) Cook. Chase my children some more. Make bizarrely elaborate…
Janet D. Stemwedel: Hey, can we talk about pseudonymous blogging? Dr. Free-Ride: Haven't you already written a bunch of posts about that? Janet D. Stemwedel: Yeah, but the blogosphere seems to be discussing it again. Dr. Free-Ride: You know I only work on Fridays, right? Janet D. Stemwedel: Get…
"For I dipped into the Future, far as human eye could see; saw the vision of the world, and all the wonder that would be." -Alfred, Lord Tennyson This weekend, the Sun is shining here in Portland, as we've gotten our first annual spell of warm, sunny days recently. It's got me thinking of the…

Based on your clue, this is clearly a strange phenomenon that exists only along the border of Wales and England, possibly due to a secret EM fence between them :)

Could it be that a tidal bore moves up this waterway and when the tide drops, these ridges of sediment result from erosion?

Just guessing here, but looking at the raised edges and their shadows, I'm wondering if this is mud that has run over a tilted slate bed, or some such similar structure.

Overbank flood deposit? Control: duration and size of flood

or

A semi careened off the m48 and into the water and created a big wave. Control: Size of semi.

Well geez, let's bring the entire aviary in on this! I think these waveforms are actually mimicking the wingbeats of an unladen swallow. The real question is... African or European?

I wonder if the pylons of the bridge there play some role in the formation.

Ooo! The M48! The road that takes me home. This picture is making me homesick for the Severn, there's some great fossil hunting to be done along there... *sigh*

Anyway. Before I saw the larger picture I was going to say that they were current formed ripples as there is definite bifurcation on some of those crests.

hmmm...at first glance, the features have an erosional rather than depositional look to them ... I might have to agree with cope above...something along those lines.