Mollusk fossils

[Rocca Hombre]

The specimens that I've collected have washed down from the Monterey Formation, there are three watersheds that flow away from this Formation, I have agatized mammal bone, oysters, and agates from clams, muscles, these are two bivalves, the same species's one is quite larger than the other, also agatized oysters

[digit]

Sounds interesting. Looking forward to seeing the images.

 

 

Cheers.

 

-Ken

[Earendil]

Interested in the mammal bone! Also want to hear the area you found them in.

[Rocca Hombre]

This agatized bone

6 hours ago, yardrockpaleo said:

Interested in the mammal bone! Also want to hear the area you found them in.

 

[digit]

Looks like the image didn't properly load. You might wish to try uploading the image again so we can all see.

 

 

Cheers.

 

-Ken

[Rocca Hombre]

This was found at the Ventura river mouth, it comes from the Monterey Formation

[JohnJ]

This appears to just be a tumbled river stone.

[abyssunder]

I'm not familiar with the Monterey fm., but it looks like something with bioerosional marks, maybe echinoid and pholad borings.

If that's correct, your specimen was in a marine environment for a long time.

[daves64]

Looks sort of like solidified foam. 

[Plantguy]

Yeah cool rock! 

I agree with the others....it does have the tumbled look of a some big mollusc/oyster shell with the rounded edges/corners that has been attacked by sponges with all those tiny holes in it but I think its as the others have already mentioned not a mollusc fossil--but rather a rock that been tumbled and bored by invertebrates while submerged in water with the larger holes being the burrow traces. If tested and it doesnt fiz with vinegar/acid I'm guessing its probably a non-sedimentary rock--non-calcareous, possibly volcanic. 

 

Im thinking the tinier/smaller holes are possibly vesicles (frothy gas bubble s/pockets) like you find in pumice/scoria in amongst layers of rhyolite. I know there were volcanics in the area and part of the Monterey formation itself, if it indeed it originated from the Monterey formation. If it was found loose in a river bed and not insitu (making up part of a conglomerate matrix) it could have come from a ways up stream possibly from other another formation in the Ventura river's drainage area. 

Cool find! Regards, Chris 

 

 

[Rocca Hombre]

Thank you for the response, the fact of the matter is I have others, but smaller in size, I have others that are not the same shape, but the same matrix, at one point it rained for years at a time, all the watersheds that flow from the formation all have the same characteristics. Some material, for instance, rhyolite, birdseye rhyolite, which they say is only found in Chihuahua, Mexico, also have others that are the same shape but are agatized and have the same markings but just older in geotime... also lots of fossiliferous, fossilized oysters, giant.oysters

[Rocca Hombre]

here's the same, but much smaller

[fifbrindacier]

I agree with @Plantguy, this is a volcanic stone, the little holes have been made by the gaz escaping from the lava.

[Rocca Hombre]

Happy New Years, hope your field trips are rewarding and fullfield with mind blowing stuff... Ok, here are more examples of other mollusks that will support my claims about fossilized mollusk

[Rocca Hombre]

Ok, here are a few photos to check out

[Ludwigia]

Nice colorful stones, but I don't see any mollusks there.

[Tidgy's Dad]

I can see them, they're showing up now. 

But I don't see bone. 

[Ludwigia]

And how else do you propose to support your claim other than showing us photos of a few stones?

[Rocca Hombre]

[Tidgy's Dad]

Rocca, are you thinking the quartz/calcite bands are shell material?  

[Rocca Hombre]

On the previous post, these fossils come from the miocene period from the Monterey Formation, and as I said in the post that they tumbled around in the surf for thousands of years, and of course you have some wear and has changed the original shape, if you had the opportunity to feel the material you will see and feel the way feel of the stone, this is something I wanted to share, this has already been identified by several geologist, so thank you for your input

[Rocca Hombre]

Yes, this is an agatized oyster, I have several of these and have been cut in half, this probably came from the lower miocene, an agate takes a minimum 50 million years to be produced...

[Thomas.Dodson]

I'm not seeing any fossil material here. Even with worn material you can usually identify the contours and separation of shell material among the polished matrix. As a frequenter of riffles I've seen a LOT of worn fossil and matrix material. If you only wanted to share and it has been identified by "several geologists", why post it in fossil ID?

 

You claim agate takes a minimum of 50 million years to be produced but then also claim the agate is Miocene, significantly younger than 50 million years.

[Thecosmilia Trichitoma]

Most of these just look like Igneous rocks with some mineral veins to me.

[Rocca Hombre]

You are absolutely right, , my bad, looking at info with out old man glasses... This an oyster, I do know that, I have others that I cut in half... If you'd like, I'll send you some...