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Above the base, there are thin beds of limestone with shale partings. These have a bluish gray color that is characteristic of the Cement City in the area:

 

post-6808-0-16625600-1324170029.thumb.jpg.930933a606db63075680b243abce9fda.jpg

 

The Cement City fossils I posted earlier came from this level. I didn't spot any fossils this day, though I certainly will return in the future.

 

Lodged into these beds is this giant 'nodule':

 

post-6808-0-94589500-1324170059.jpg.bcfa4d1987125c19ca2888cfdf90c585.jpg

 

This may be a bioherm, which is a small, organic, reef-like build-up on the sea floor.

 

Overlying these beds is the 'handy bench' bed we saw before. Above this, we see a fresh exposure of the nodular limestone:

 

post-6808-0-44533800-1324170097.thumb.jpg.a36910f608a35039dca1bb056e14ab01.jpg

 

This bed is puzzling to me. It looks brecciated, yet delicately preserved brachiopods can be found in the shaly matrix. I haven't seen this facies in any other exposure. Normally, there is a single bed of limestone in its place.

 

At top, there is a single, variable bed of limestone that shows cross-bedding in places:

 

post-6808-0-07998500-1324170202.thumb.jpg.b23b89f33a85f5664a22d5fa1c9b9416.jpg

 

This is the same stuff that caps the big waterfall up-stream. It is probably the bioclastic unit occasionally found in the region that has been called the 'Corbin City' in the past.

 

The thin bedded sandstone within the Chanute Formation, as seen on top:

 

post-6808-0-76410800-1324170227.thumb.jpg.332f187bc781938aa972bc7110fe7a21.jpg

 

Because the sandstone here seems to occur in isolated blocks, I suspect it may have slumped from a higher level. I'll need to search for more exposures further upstream to see how it fits into the column. It may be equivalent to the sandstones in the Chanute we saw earlier in a road cut.

 

And lastly, the handiwork of beavers can be seen all along the creek:

 

post-6808-0-90948700-1324170272.jpg.237f00c1e126e67805063a30c9424821.jpg

 

The little jerks have been quite busy this year. :)

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As I looked at this photo:

 

post-6808-0-05882400-1324187366.thumb.jpg.5cb9b1be0c70522f580a18e1cc73f4b9.jpg

 

 

I noticed a tongue-shaped object (circled). I'll have to return and check it out.

 

Also, three productid brachiopods are arrowed.

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Since my local excursions have been turning up empty fossil-wise, I will tide you over with some specimens from the Winterset Limestone found around the Kansas City metro....

 

I shall start out with the trilobite Ameura. Here is its head:

 

post-6808-0-84646900-1324290215.thumb.jpg.6e625dd77152f9d59483cdd44b379bd8.jpg

 

And its tail:

 

post-6808-0-47522900-1324290232.jpg.5a0970353819b9c006f533b526518751.jpg

 

Cephalopods can be found in the oolitic beds. Here is Metacoceras:

 

post-6808-0-94223700-1324290334.thumb.jpg.0a11456b85a2e4a0f56bb340e9401af1.jpg

 

Liroceras:

 

post-6808-0-95563500-1324290361.thumb.jpg.ea9ae4f9038c83c437e0bba25eec8b76.jpg

 

Stenodomatoceras:

 

post-6808-0-94481200-1324290400.jpg.fe48e3c1f57e470f4ba923c4b061a950.jpg

 

I've had this specimen for 24 years, and just tonight, I learned its genus name.

 

Alongside the cephalopods are many types of gastropods. Here is Strobeus:

 

post-6808-0-84837100-1324290559.jpg.6cf28c0863c8cd36c693358d68319836.jpg

 

And Euconospira:

 

post-6808-0-05250300-1322388066.jpg.60fd6b61435ef53ad3327f721fd13a95.jpg

 

Pelecypods are plentiful as well. These large pectens are clustered together:

 

post-6808-0-58702200-1324290662.thumb.jpg.c2b867c2e49f9fda4834d904543dd158.jpg

 

This Aviculopecten is in dolomitized limestone:

 

post-6808-0-84136800-1324290721.thumb.jpg.11e94966c4a9aad69e2686d73dcf32e5.jpg

 

Mollusks of all kinds can be found in the bands in this rock:

 

post-6808-0-83780900-1320741160.thumb.jpg.dbf579e45e3cfda198b2b2e0207e7d31.jpg

 

Crinoids are present too. Here is a calyx of an Ethelocrinus magister, along with some stems and plates:

 

post-6808-0-88346100-1324290966.thumb.jpg.cba829e599a8871d6c55b38ae98589b1.jpg

 

Plants are often encountered in the Winterset. The strap-like leaves of Cordaites are the most common:

 

post-6808-0-48573500-1324291054.thumb.jpg.574e8fbe006a98aaf1452364bbe7c09d.jpg

 

Cordaites may have formed mangroves along the coastline.

 

And in a few isolated spots, ferns can be found. This is Pecopteris:

 

post-6808-0-70091200-1324291125.thumb.jpg.4133b895ccd7c97e415c7957974ba64b.jpg

 

Well, that's all for now.

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The Ameura trilobites are my favorite of the bunch although the entire Winterset faunal-floral assemblage you posted is spectacular.

Thanks for another amazing installment Missourian! :D

image.png.a84de26dad44fb03836a743755df237c.png

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I went back to the city park a second time to do some follow-up on the strata in the big creek. I was bugged by the apparently dislocated blocks of sandstone in the Chanute Formation. These two above the cliff are obviously dislodged:

 

post-6808-0-94935900-1324456691.thumb.jpg.df8b1ee77bc9df546e00616b6a6677e8.jpg

 

Also, note the second (possible) bioherm on the right.

 

I followed the big creek back upstream to see if I could find the sandstone cropping out near water level. Not too far above the first waterfall, I found this:

 

post-6808-0-69249300-1324456997.jpg.3bfbbdcb0dbf84808a0ee330a47ebb7e.jpg

 

These sandstone beds are about 3 or 4 feet above the Cement City 'cap rock'. Ok, good enough. I then went back to 'No-Trespass Falls', and I noticed this outcropping of rock sitting directly on top of the Cement City:

 

post-6808-0-68309600-1324456873.jpg.c35318058a8c13e22b224e785befea48.jpg

 

Hmmmm....

 

There was no other indication of any such beds above the falls ledge. Could this be the sandstone at a lower level? I went over to take a look. Well, no, this rock looked an awful lot like the Raytown Limestone. But there is a problem. There should be ~15 feet of shale and sandstone between the Cement City and the Raytown. How could such a widespread formation be missing, and then be present so close on both sides?

 

Well, I stared at the outcropping for a few minutes. "These rocks should not be here.... these rocks cannot be here.", I kept saying to myself. I had to use Occam's Razor for this one. "This outcropping must be artificial." As I studied the rocks, I noticed that some of the beds didn't line up quite as they should. There would be thin beds, and then a large chunk would be sitting next to them. I looked across the creek and noticed a somewhat similar piling of rocks. Since the road crosses the creek less than 100 meters away, I guessed that these stones could be the remains of an old bridge foundation. Another possibility is that an old mill or dam was built atop the waterfall. I would think such structures would have had exteriors made up of mortared blocks, but any such facades have been completely removed. So that's my theory, and I'm sticking with it. :)

 

Now that I solved that mystery, I then went back down to the cut bank with the full Cement City to do some more recon. I remember seeing a small stream entering the big creek on the opposite side. I followed it to find outcroppings of the sandstone and whatever else turned up. Pretty quickly, I found another waterfall over the 'cap rock':

 

post-6808-0-46178500-1324457115.jpg.319f992e75443282825df38777ffffcc.jpg

 

On the left, there is another block of Chanute sandstone. Here it is up close:

 

post-6808-0-18521200-1324457225.thumb.jpg.e7f12209f0bb39551d097c50caf4dea6.jpg

 

Pretty nice stuff. It was getting late, so I didn't have a chance to look for trace fossils. I will do that next time.

 

Up ahead, there are a few limestone beds of the Iola Formation, and more of the sandstone in situ:

 

post-6808-0-12715100-1324457328.jpg.7d48f674bd06b97ec97509f46427dbad.jpg

 

The Iola may have slumped a bit here, but probably not too much.

 

Speaking of slumping, that isolated 'exposure' of 'Iola Formation' high above the big creek mentioned in an earlier post may instead be chunks of Wyandotte Formation that had slid down from above. For those doing field work, the possibility of outcrop slip should be kept in mind.

 

The more prominent sandstones seemed to lie below this. This stratigraphic arrangement is similar to that of the formation in a cut bank near my old home. Although it no longer exists, I did draw up a chart of the exposure before they covered it over:

 

post-6808-0-84898700-1324459955.thumb.png.7c495454de448be06281cb63b32b4814.png

 

At least the former outcropping earned me some points in sed-strat class.

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The city park continues on the other side of the main road, as do the cut banks as we follow the big creek upstream. After a couple bends, I came across this beautiful scene:

 

post-6808-0-42789500-1324539640.thumb.jpg.72cbe03284717cc8ea943fa8cfd07aab.jpg

 

This is a really nice exposure of the Iola Formation. The main part of the Raytown Limestone was cleanly sectioned along a joint:

 

post-6808-0-47689700-1324539665.thumb.jpg.25b33a707ece0c44cb8f786e0785db53.jpg

 

As you may recall, the phylloid alga Archaeolithophyllum is abundant in this unit. It causes the wavy bedding in the middle.

 

The crinoidal bed at the base of the Raytown is well exposed. Again, this is a helpful marker bed if the underlying Muncie Creek is not apparent:

 

post-6808-0-68225900-1324539682.thumb.jpg.fbd55d8015b2a8c58cff3b586db65958.jpg

 

I then scrambled over to the other side of the outcropping to view this excellent exposure of the entire Iola. The top of the Chanute Shale is tucked under the ledge above the water:

 

post-6808-0-77323900-1324539700.thumb.jpg.a07d55608df14a161d80fc15eb66c36e.jpg

 

That ledge, which is the Paola Limestone, kept my feet from getting wet. Much of the Muncie Creek Shale above was covered with moss:

 

post-6808-0-70064100-1324539716.thumb.jpg.fc4ba26081e3b3b06f280bc71813d5d1.jpg

 

That didn't stop me from finding this concretion:

 

post-6808-0-64117400-1324539730.thumb.jpg.cdeb53c0b4a9b19930e8be4db8bdc646.jpg

 

Later, I popped the nodule. There was some vague chitin-like material inside. This may be an example of fish regurgitation:

 

post-6808-0-35228300-1324539895.jpg.89cebc82ce84b6e0608b7dcb3f33d074.jpg

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The next unit above the Raytown is the Liberty Memorial Formation. Unfortunately, this fossiliferous shale was completely covered.

There were some exposures of the Wyandotte Formation further up in the woods, but I didn't scramble up to them. Instead, I checked out a modest outcropping that I'd recently noticed back at the road:

 

post-6808-0-89337500-1324706117.thumb.jpg.bc72b0efc3f9bd69f325bca012818198.jpg

 

This includes much of the Argentine Limestone, and possibly the Frisbie Limestone and Quindaro Shale at the base.

 

A nice pair of Neospirifer brachiopods can be seen here, though I was afraid the chunk of rock they were in served as a keystone of sorts:

 

post-6808-0-41707500-1324539986.thumb.jpg.b5f0ab7d903d30f9c80a747c682422b0.jpg

 

And finally, a stratigraphic study would not be complete without a chart:

 

post-6808-0-93690500-1324540042.thumb.png.9ea7339401d564dda0977b16270ab821.png

 

That's all for today.

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Well, I'm stuck here at work on Christmas Eve morning. I have no fossils, rock exposures, or cameras to play with. All I have is MS Paint. So, here's a quick rundown of the Pleistocene story of my neighborhood:

 

post-6808-0-03439600-1324743668.thumb.png.5e1b9cca169ee965c9cf246612d07b1a.png

 

I'm still trying to sort out why bedrock tends to be exposed on the southern sides of streams. I think it's due to glacial action or loess deposition (or both).

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On 12/24/2011 at 10:40 AM, squalicorax said:

any luck hunting down some horseshoe crabs ?

 

None in my neighborhood (that I know of).

 

I do have a few Euproops from Knob Noster, but I didn't find them myself. All material from there was collected by the landowner back in the 1990s.

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  • 2 weeks later...

Since we continue to have 50 to 70 degree days in January (!!), I made yet another strata recon walk. This time, I followed the creek downstream from my childhood home. After about a mile of re-engineered creek channel, I made it down to an exposure of the Cement City Limestone:

 

post-6808-0-46029400-1325924467.thumb.jpg.9053b6b8991b464be38a7c32650aa67f.jpg

 

As you can see, a nice waterfall has formed over the thick bed that is the base of the unit. Here's another view:

 

post-6808-0-69710100-1325924535.thumb.jpg.2ef7171888f00e5be2355da8480c493f.jpg

 

The Quivira shale is in shadow beneath the ledge. Visible just upstream, you can see where they dumped a mass of concrete that the city piled over the formerly productive middle part of the Cement City.

 

About fifty yards further up, a small patch of the fossiliferous beds can be found:

 

post-6808-0-81257900-1325924555.thumb.jpg.137a72c26ffba7626523c46a63fcd152.jpg

 

I guess the city missed this. :)

 

As I continued to walk downstream, I came across this bank made up of loess:

 

post-6808-0-57043300-1325924572.thumb.jpg.e36dde979a5cd0103ef298080793e128.jpg

 

Further down, I found this exposure of Cement City along an old, abandoned creek meander:

 

post-6808-0-69170000-1325924593.thumb.jpg.e2fbcd39ad36d4de8cfe39fad4e3aa5a.jpg

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After making my way through a tangled thicket, I dropped back into the creek when I spotted some limestone in the bottom of the channel:

 

post-6808-0-39951000-1325924676.thumb.jpg.a790688baa35fe5143d2ab1a724be68a.jpg

 

This is the Westerville. There is a three-foot section of the limestone on the side:

 

post-6808-0-80787800-1325924689.thumb.jpg.bb6e285a58458e65c75b46e93e89de8f.jpg

 

Better yet, the shale units above the Westerville are present as well:

 

post-6808-0-46181500-1325924706.thumb.jpg.4b6196bb6710abeaa267912d9d60ee9b.jpg

 

The greenish unit is the Nellie Bly Formation. The black, platy shale at top marks the base of the Quivira. The little stream of water that flows over the surface kept it free of algae and debris.

 

My main goal today was to find these shales, which fills a big gap in my stratigraphic column. Since I didn't find any fossils, I'll leave you with a couple specimens collected from the Quivira elsewhere....

 

Possible fish skull in a limestone concretion from near Raytown, Missouri:

 

post-6808-0-53287200-1322436064.thumb.jpg.b49b5059a3d1609c64a43f2a1cfa82f5.jpg

 

Unidentified cone cluster on black shale from the same site:

 

post-6808-0-80611900-1325924826.thumb.jpg.47d56076131eacad443a8cd350965568.jpg

 

This was one of those sudden pop-WOW finds that make my day (if you know what I mean). Fortunately, as the specimen was drying out and shell was beginning to flake off, my hunting partner happened to have a spray can of flat finish in the car.

 

Oh, and a strat column for the day:

 

post-6808-0-35896100-1325930090.png.f66690cc12f726a17ffd1fea48f75a6c.png

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I just read that in localized spots, the Nellie Bly Formation fills channels cut into the underlying Westerville. This photo illustrates an example of this not too far from where I live:

 

post-6808-0-64482800-1325967152.jpg.54936edd3b1d5707b3bd5cd5cef62498.jpg

 

Nellie Bly is 'NB' and Westerville is 'Cws'. This may explain the spots I mentioned above where the Westerville Limestone is anomalously thin. So keep this in mind when trying to figure out the stratigraphy of an area. :)

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Beautiful hunting location and finds. Great thread also! Thanks for sharing!

"The road to success is always under construction." Author Unknown.

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Thanks Missourian! I look forward to new posts on this thread and walkin through the woods with ya! Nice scenery, good pics and I learn something new every time we stroll through your backyard! :)

It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.

Charles Darwin

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Thanks everyone for the comments. I love the diversity of the Pennsylvanian, and it's nice seeing outcroppings in a natural state.

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Yes, the places are very peaceful looking too.. Those are

my favorite places to hunt (quiet streams, back roads,

anywhere off the main path..

Welcome to the forum!

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These strolls with you are some of the most engrosing and informative topics in recent memory: Thank You!

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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Here, I'm returning to the big hill featured at the beginning. When I started this thread, I kind of breezed through the descriptions of the strata. I'd like to tie up some loose ends.

 

Here is an exposure of Farley Limestone tucked away in a gully:

 

post-6808-0-55691700-1326007112.thumb.jpg.c3eb36da1490c42acf7eef42491339dc.jpg

 

It includes both limestone beds and the intervening shale. Again, note the joint pattern in the upper limestone.

 

The lower oolitic limestone can be seen here with what is probably the top of the Island Creek Shale. I'm not sure of the nature of the thin beds at the very bottom:

 

post-6808-0-65972900-1326007131.thumb.jpg.4f74add73e5e1239ed1192b2084ce35c.jpg

 

The Farley is extremely variable in thickness, lithology, and stratigraphy. Besides featuring two limestones and a shale, the exposure here is not necessarily representative of the unit as a whole.

 

The Plattsburg Formation, on the other hand, is more consistent. The Merriam Limestone appears pretty much as it did in the road cut shown before:

 

post-6808-0-38769100-1326007159.thumb.jpg.1bc0c2568bf67046b13a0bcd8556846b.jpg

 

At the bottom of the Merriam is a single layer of limestone that weathers into thin beds. Here it is again as a loose block:

 

post-6808-0-17604900-1326007709.thumb.jpg.dd99855f507debbbbdb770a7e2dd7c90.jpg

 

I didn't see any similar bed at the road cut exposure shown several posts back. The Hickory Creek Shale is covered here, but its position is marked by a wide bench in the excavation.

 

Being near the summit of the hill, there's not much left of the Spring Hill Limestone here:

 

post-6808-0-74994300-1326007723.thumb.jpg.c8e3e5e41c26cc94788710cc97707652.jpg

 

Here is an improved strat chart:

 

post-6808-0-85951300-1326012337.thumb.png.cb6c15a9f4788710923b8486d02f49a7.png

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I recently found an old photo from the early 1990s of the nice sandstone exposure near my childhood home:

 

post-6808-0-77842900-1326056274.jpg.e5a59071fd60e69a28efeb80deacd0a1.jpg

 

Sorry about the leaves. :) The entire section was about 12 feet thick.

 

Here is the strat chart I included in an earlier post. This time, I numbered the units:

 

post-6808-0-65446400-1326056250.thumb.png.9a2269ed0b89d5f830224988c8630a5d.png

 

1. Claystone. This contained thin coal lenses. I believe this unit is in contact with the underlying Cement City Limestone.

2. Shaly Limestone, single bed. This contains ostracods, wood fragents, and poorly-preserved pelecypods and bellerophontid gastropods. I happen to have saved a piece:

 

post-6808-0-85277600-1326056403.thumb.jpg.0ab57618778409f4cdbc5bc0602e6e8e.jpg

 

Note the partial large Myalina at bottom.

 

3. Calcareous sandstone, thin-bedded. This contains ripple marks and trace fossils. As shown before in this thread, here is a slab from this exposure (or the one that was 100 meters or so upstream):

 

post-6808-0-52710600-1322767909.thumb.jpg.d1c5d7f6f9ba87ee055a015d8a4dec84.jpg

 

4. Shale (top of Chanute). Thin coal lenses were present in places. Plant fragments were found as well.

5. Limestone (Paola), single bed.

6. Shale (Muncie Creek). The unit was ill-defined, but a couple phosphatic concretions were found.

7. Limestone (Raytown). Ill-defined. Only scattered fragments were present. Trilobite parts were present in one:

 

post-6808-0-55824800-1326060823.thumb.jpg.6c90dae71464de58759861ff3a62f5c0.jpg

 

post-6808-0-52249400-1326060852.jpg.88e34f0e4306f102413ab5b1a617e184.jpg

 

It's possible they were in the Paola or even in a glacial erratic. I'm not sure of the genus. It doesn't quite look like Ditomopyge, and it certainly isn't Ameura. Any trilobite specialists out there have any ideas?

 

Speaking of glacial erratics, there was an old, sorted glacial morraine draped over the bed of the creek here:

 

post-6808-0-16843000-1326056829.jpg.2f0209bd1562fb89d41ddba9076b7245.jpg

 

The chunk of displaced Block Limestone that is 'Dracula's coffin' can be seen below the hanging tree on the right. :)

 

As metioned before, this exposure was covered over when the city re-channeled the creek. Here is the site now:

 

post-6808-0-59615900-1326060896.thumb.jpg.736bd35542346193f58b6c53973de36a.jpg

 

This was an excellent, nearly complete exposure of the Chanute. It's a shame the city thought they had to shore up the creek slope here, even though there was nothing but woods above.

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It's dark outside, so I can't hunt for fossils. I'm at work, so I can't take photos of fossils. So what's left to do? Well, I can draw something in MS Paint.

 

In the previous post, I included this photo of the boulder deposit that used to be in my creek:

 

post-6808-0-20836900-1326343558.jpg.3de8aab03b3fe21d4ec66e4efaa865d0.jpg

 

Here is my interpretation of its history:

 

post-6808-0-98120200-1326353090.thumb.png.04ef6abd63ebd437527a26b44965c4ed.png

 

So the backstory of that little spot of earth goes something like this:

 

1. Mountains or hills somewhere are eroded, and the resulting sand eventually flows into a warm, shallow sea.

2. Wave action moves the sand around. Ripples form in the surf zone, where small creatures burrow into and crawl across the sand.

3. Mud from an advancing delta covers the sand. As the sea deepens, carbonate mud begins to be deposited.

4. Many hundreds, if not thousands of feet of sediment are deposited above. The sediments are compressed and mineralized.

5. Eventually, all the overlying strata are removed by erosion. A valley network is established in the landscape.

6. Glaciers move in, eventually melt, and deposit rocky material upon the surface. Certain characteristics of the ice flow and the terrain cause debris to concentrate into a morraine along a slope.

7. Over time, the elements remove the finer clay, sand, and gravel from the morraine. A jumble of boulders remains.

8. The boulders are covered with stream sediments, material creeping downslope, or perhaps loess.

9. The modern creek forms a cutbank and erodes into the unconsolidated material and bedrock. Resistant to movement by stream flow, the boulders pretty much stay put.

10. The city brings in a bunch of land-moving equipment, strips out the boulders, and covers everything in rock-filled gabion boxes and landscaping fabric.

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Wow, thank you for sharing! This is such a great report! I love the ripples in that sandstone. I can't see too well from the picture, but do they appear pretty symmetrical? Beautiful stratigraphy as well!

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