creek find 3

[Baddadcp]

Arundel Formation. Maryland. Lower Cretaceous.

 

What say you?

 

[Raymond Douglas]

Looks like a concretion

 

[ynot]

+1 for concretion.

[Darktooth]

Concretion, which sometimes form around a fossil. Give it a whack, there might be a hidden prize in the middle.

[Baddadcp]

5 hours ago, Darktooth said:

Concretion, which sometimes form around a fossil. Give it a whack, there might be a hidden prize in the middle.

There are typical concretions in every formation. They look the same and are usually common as heck. There are concretions here, common , and take a certain form. This is not it. It is becoming a disappiontment that you guys never ask for more information. But part of the game is learning the rules and what you are dealing with. Thanks for your learned opinions, I will take it under advisement.

[Rockwood]

27 minutes ago, Baddadcp said:

There are concretions here, common , and take a certain form.

Why do you think one form is all there should be ?

[Tidgy's Dad]

This one is a layered concretion with some of the outer layers partly broken and eroded away.

[Darko]

Concretion

[Darktooth]

2 hours ago, Baddadcp said:

There are typical concretions in every formation. They look the same and are usually common as heck. There are concretions here, common , and take a certain form. This is not it. It is becoming a disappiontment that you guys never ask for more information. But part of the game is learning the rules and what you are dealing with. Thanks for your learned opinions, I will take it under advisement.

If that is the way you feel, then why not just provide any pertinent information? But yes it is still a concretion.

[Fossildude19]

3 hours ago, Baddadcp said:

It is becoming a disappiontment that you guys never ask for more information. But part of the game is learning the rules and what you are dealing with. 

 

What other information should we be asking for?

What are your thoughts as to what this is?

 

We can only go by what we are seeing in the photographs. 

Creek finds can be erratic, as flooding and erosion expose numerous layers.  This could account for the differences in what you usually see in concretions.

If you question our opinions, you should take it to a nearby university, or museum to be looked at. 

It is always easier to make determinations of ID when you are holding the item or able to see it in person.  

 

 

[doushantuo]

found where?(map image from Jud/ROY.SOC.LOND/2015)

 

[DPS Ammonite]

Concretion. I do not see any egg texture. I do see coarse sand/ small gravel in the outer layer and the inner layer which suggests that this is not an egg fossil. 

[ynot]

There are several minerals that will form concretions and they do not look the same. Even concretions of one mineral type can have different appearance (they do not all look the same). One feature that is common among concretions is an "onion skin" layering, which is evident with the way the concretion will weather.

If You think some information is pertinent, why do You want Us to ask for that information. It would make more sense and facilitate an ID if You provide all the information that You think is pertinent, then We do not have to guess.

 

[Rockwood]

Perhaps 'cause it's those unknown unknown that get ya.  

[Auspex]

15 hours ago, Baddadcp said:

It is becoming a disappiontment that you guys never ask for more information.

OK, what ya' got? I hope it's more than "Arundel Formation. Maryland. Lower Cretaceous. What say you?"

Why don't you tell us why you don't think these are concretions? Please cite your evidence.

[Baddadcp]

50 minutes ago, Auspex said:

OK, what ya' got? I hope it's more than "Arundel Formation. Maryland. Lower Cretaceous. What say you?"

Why don't you tell us why you don't think these are concretions? Please cite your evidence.

Fair enough. Premise one, as I said, it is divergent from typical concretions of the area. The Lower Cretaceous in Maryland is well known for a variety of fossils and formations. Primarily ironstone and mud stone. See images. No shortage of concretions, just this is an aberration for the formation. Premise two, The gravel bars are of a material that I have seen for over fifty years, and though there have been grainy quartzite cobbles or even sandstone cobbles, they always have an stain. The environment is rich with red clay and colors everything. This has a color aberration for being in the environment. Premise three, the exposure is new, rich in fossils, and dropping unusual material every storm. I believe ANYTHING is possible in this exposure. Look on PBDB for "Branchville" and the other three citations for the immediate area then ask what is possible from this exposure. It IS NOT Muirkirk and doesn't look much like the material that comes out of Dinosaur Park. Premise four, the shape is unusual for the typical mud stone and ironstone float. If you look at Russian eggs and recent Chinese eggs, the nature is loose sandstone. A perfect example that has been beat in the creek would not likely have shell left (if what I see is as loose as it appears in the photos of defined eggs) see image. Premise five, It appears to have a bit of shell. Visible as a tangent on the third pic, lower right. It also appears to have bits of other material. It could have been a cast and collapsed, or could be a coprolite. It could very well be a concretion. But I promise you, I wouldn't waste you time if I didn't think there was something worth discussing. See image. Now, I am sure every one that has said it's a concretion has vastly more experience than I do in the field, and that's okay. Who has great experience in EASTERN Cretaceous fossils? The closest thing would be Hell Creek, but those come right out of the formations. These are wet environment and erode out. So are typically abused a bit.

[Miocene_Mason]

On 9/5/2018 at 7:37 AM, doushantuo said:

found where?(map image from Jud/ROY.SOC.LOND/2015)

 

See that dark band, in that

 

I think it’s a inclusion (like an agate rock or something like you see in conglomerates) that’s had a concretion form around it.

[Auspex]

On 9/5/2018 at 8:54 PM, Baddadcp said:

it is divergent from typical concretions of the area

 

On 9/5/2018 at 8:54 PM, Baddadcp said:

this is an aberration for the formation

 

On 9/5/2018 at 8:54 PM, Baddadcp said:

The gravel bars are of a material that I have seen

 

This establishes that , in your experience, the material is unlike any other you have seen from the formation.

Given the observable inconsistencies between your samples and known fossil eggs (not the least of which is the thick, concentric 'rinds' of your specimens), Occam's Razor demands we consider more likely alternative identifications. I propose that these are sandstone concretions, from an isolated depositional deposit (possibly a lag deposit) with diagenetic processes that differ from the rest of the formation.

Since it is this unusual deposit that generates the mystery, let's look to its geology for clues. What are the fossils in this deposit? Do they show signs of wear, possibly from redeposition by wave and water? Do they show an in-situ orientation? Are there signs of lamination in the sediment?