Ron E.

Here's A Strange 'un

80 posts in this topic

slickenside

more

This is very common in Texas, Hyway 35 going into Bell County from the south has some and over in Killeen also. You may also find these forming in clay here, mainly when Calcite fills in the cracks. Common in the Garyson Formation again along 35. What am I talking about, I had to clean the stuff out of my water heater once a month when living there!

Slickedsides are indicative of movement, usually along a fault plane, but also associated with mass wasting. It results in the polishing of the surface. It is for these reasons that I don't think this is stone displays that kind of structure.

While not familiar with the geology of your area, the area above, and below, the lineations exhibit classic styolites structure. The lineations are along the axis of the plane of one of the styolites, and orthogonal to the stress that caused it.

styolites

styolites (see the bottom of page 20)

Look at the photo in THIS link. Now, imagine the structure along one of the lines that is perpendicular to the bedding plane... viola!

Share this post


Link to post
Share on other sites
In S. Florida we occasionally run into Gypsum seams- lines of needlike xls that look similar to that. on the specimen below you can see that (in real life) by looking at the edge (unfortunately, my camera doesn't do well on things this small).

post-1313-1248089533_thumb.jpg

alright, frank, I am always glad to be corrected and to learn!

and personally, i do not think it is a slickenside or a styolite... it doesnt quite fit the definition of either..

my theory is that the limestone, while forming, was two different temperatures/density... and so the wamer particles rose straight up, cooling off as they went, until theyve cooled enough to stop moving....

(its just a guess.)

Share this post


Link to post
Share on other sites
and personally, i do not think it is a slickenside or a styolite... it doesnt quite fit the definition of either..

Why not? I explained why I think that it is not slickenside, why do you not think styolites?

Share this post


Link to post
Share on other sites

the links for the styolites you gave all mentioned something having to do with pressure... this does not at all look like it formed by pressure... it is too even/straight for that.

same with the slickenside.. "formed by one rock against another"... i do not think this has to do with physical happenings after the rock was formed... this rock was originally created like this, not deformed after being formed.

Share this post


Link to post
Share on other sites

I agree with Solius, looks like a Styolite of some sort. Slickenslides are way smoother and look like a smooth surface with just some scratches while styolites often have some structure. I doubt it's a coral as the rock just doesn't look right. Can you see any cross sections of the chambers? I could see it being a gypsum mold as that is a fairly common mineral in the type of formations in Texas. Since you had the ebb and flow of the sea over time Gypsum may have formed in lens shaped ponds at times and maybe this is just a remnant of a now dissolved lens.

Share this post


Link to post
Share on other sites

what about styoslickenesque? compromise is the essence of diplomacy when what's at stake is your brain exploding from trying to understand semi-fluid dynamics in geology.

p.s. - that was a rhetorical comment. i'm abandoning this topic for less stressful ones. (hah!)

Share this post


Link to post
Share on other sites
the links for the styolites you gave all mentioned something having to do with pressure... this does not at all look like it formed by pressure... it is too even/straight for that.

Click the high resolution pic.

The pressure involved in the formation of styolites can be due to the over burden, and not always tectonic stresses. The area above, and below, the linear feature appear to be classic styolitic structure resulting from pressure dissolution.

Share this post


Link to post
Share on other sites

Here's another hi-res pic, showing more detail not seen in the originals.

post-1880-1248118748_thumb.jpg

Share this post


Link to post
Share on other sites
Here's another hi-res pic, showing more detail not seen in the originals.

post-1880-1248118748_thumb.jpg

That changes everything. You can now see the same pattern in the bottom of the recess. That used to go all the way across the rock.

I still have no clue what it was, but it definitely negates my theory. Now it does resemble some sort of coral formation.

Share this post


Link to post
Share on other sites

i tole ya'll from the start that it's obviously a styolite. why are ya'll being so hard-headed?

"Do I contradict myself?

Very well then I contradict myself,

(I am large, I contain multitudes.)"

Whitman

Share this post


Link to post
Share on other sites

p.s. - that last picture convinced me that i was dealing with forces i'd never before seen or experienced, which is so often the case whenever i find myself not in abject, genuflective concurrence with all the RKIs on the forum. seems sometimes that my ole cap and bells just tees me to a fit!

love,

tracer, the exspurt

(p.s. - an "ex" is a has-been, and a "spurt" is a drip under pressure, so there you have it)

Share this post


Link to post
Share on other sites
Click the high resolution pic.

The pressure involved in the formation of styolites can be due to the over burden, and not always tectonic stresses. The area above, and below, the linear feature appear to be classic styolitic structure resulting from pressure dissolution.

First, they are not formed by pressure, they are formed by calcite crystals forming in clay, calcium carbonate comes down with water and really can grow large slabs of these crystal structures under ground, some get so thick that people who find them think they are fossil wood. They always follow the cracks, no tectonic stresses and no pressure, just a bunch lime clay. Come down here and look in these local caves and see some of the things hanging from the from them they are still growing. The name they used for this action is called "slickenside" and is referenced to the marks it leaves, this term cover a lot of territory and is general in it's meaning.

Share this post


Link to post
Share on other sites

the way JP just explained it seemed to fit.... except I cannot imagine where the 'cracks' would be that it follows..

Ive been in plenty of caves, and that was my first thought.. but I cant imagine this thing forming in a cave...

Ron, look at the little holes... do they seem like air bubbles, weathering, little fossils, other chunks of (missing) limestone/calcite crystals, etc...

Share this post


Link to post
Share on other sites
Ron, look at the little holes... do they seem like air bubbles, weathering, little fossils, other chunks of (missing) limestone/calcite crystals, etc...

If you're referring to the holes beginning about 1/4 the way down, not air bubbles, not weathering, more like cleanly missing chunks.

Share this post


Link to post
Share on other sites
If you're referring to the holes beginning about 1/4 the way down, not air bubbles, not weathering, more like cleanly missing chunks.

same with the larger holes, too?

Share this post


Link to post
Share on other sites
the way JP just explained it seemed to fit.... except I cannot imagine where the 'cracks' would be that it follows..

Ive been in plenty of caves, and that was my first thought.. but I cant imagine this thing forming in a cave...

Ron, look at the little holes... do they seem like air bubbles, weathering, little fossils, other chunks of (missing) limestone/calcite crystals, etc...

Clay, at one point lay on top of the ground here, drys out gets cracks and is covered with whatever, years later water trickles down and starts laying down calcium carbonate crystals bottom to top, dissolving out the the whatever and following the crack you then get this pattern. Take a stalactite cut it and look at it under a loupe, you will see the crystals lots of them.

Share this post


Link to post
Share on other sites
Clay, at one point lay on top of the ground here, drys out gets cracks and is covered with whatever, years later water trickles down and starts laying down calcium carbonate crystals bottom to top, dissolving out the the whatever and following the crack you then get this pattern. Take a stalactite cut it and look at it under a loupe, you will see the crystals lots of them.

what youre describing just seems to be fossilized mud cracks... and this certainly is not a mudcrack...

maybe if the matrix was denser than whatever caused those lines, they crystallized upward?

maybe it just is a type of crystalline limestone.

Share this post


Link to post
Share on other sites
Come down here and look in these local caves and see some of the things hanging from the from them they are still growing. The name they used for this action is called "slickenside" and is referenced to the marks it leaves, this term cover a lot of territory and is general in it's meaning.

What you are describing is a process associated with soil mechanics. this thing appears, at least from the photo, to be a carbonate stone, and from my understanding, it could not be associated with karst.

I am very familiar with karstic processes. I wrote several papers back in the day. Too, my area is one of the finest in the world for karst topography. What you are referring to is aragonitic flow stone. I have seen thousands of examples, but none that I have seen resemble what is pictured.

Can you provide a paper(or abstract).

Share this post


Link to post
Share on other sites
same with the larger holes, too?

10-4.

Share this post


Link to post
Share on other sites
10-4.

Is it a mudstone, or a carbonate?

Share this post


Link to post
Share on other sites

NO, no, no. If you have not see it you will not understand it, most of the time you can not even pick this stuff up. I falls apart. But that's not the point, we are talking abut the pattern, only.... And they are not fossil mud cracks, they are not karstic processes, have you ever seen this before, yes or no? It has been forming here for millions of years and you can see it in just about ever formation there is. When they were building the new side roads on 35 just 2 years ago, they moved most of the side of a hill and after a heavy rain most of the side of the hill was crystal. It was a solid mass sparkling in the sun. It just came apart to the touch. But all of this means nothing anyway, "slickenside" has a lot of meanings and all are in use today but the one in use here is for the pattern only. That Pattern is found in clay and limestone where ever, the man has a rock with a pattern in it, none of your ideas hold water, it was formed when it was still clay, folks calcium carbonate comes and goes, but the finger print remains......

Share this post


Link to post
Share on other sites
Is it a mudstone, or a carbonate?

Basically, the rock's appearance looks identical to the limestone that is abundant in this area. The prominent ridge is what attracted my attention, upon further examination, the whole rock is pretty enigmatic for this area. But if laid next to a classic piece of limestone rip-rap, it would blend right in.

Share this post


Link to post
Share on other sites

Let's try to narrow down what it is we're dealing with here. Put some acid on it, both on the patterned surface and on another. Might not tell us anything, but it might eliminate some loose ends.

Any other simple mineral tests that can be thought of?

Share this post


Link to post
Share on other sites
Basically, the rock's appearance looks identical to the limestone that is abundant in this area. The prominent ridge is what attracted my attention, upon further examination, the whole rock is pretty enigmatic for this area. But if laid next to a classic piece of limestone rip-rap, it would blend right in.

That's what I was talking about there is the fingerprint, and thats what I was using to describe it is just a term, nothing more. Limestone, lots of calcium carbonate.

Share this post


Link to post
Share on other sites

so it was just a type of crystallized limestone..?

a method of crystallizing, so to say?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.