Help to ID fossils from Latham Shale in Cadiz, CA

[brotherbbock]

We spent some this weekend with the kids poking around in the Latham shale of Cadiz, CA.

 

The first fossil in the pic is obviously a trilobite of some kind, any specifics are appreciated.

 

The second round one with the bump in the middle and a surrounding spongy looking matrix was found pretty close to the trilobite. Any ideas on that one it has me stumped?

 

The last pic I believe are manganese dendrites? My question with that is are they Cambrian in age as well.

 

Thanks everyone....

[Fossildude19]

The first item looks like an Ollenelus sp.  trilobite cephalon.

LINK

Second looks like a concretion.

The third looks like a pseudofossil - agree it is manganese dendrite.

Not sure how long those take to form, but I would guess they are not Cambrian in age.

[Sagebrush Steve]

The first is a nice Olenellus trilobite.  The second, I believe, is an ooid, which is a form of limestone concretion.  I've attached a technical paper that shows pictures of oolitic  limestone features from the Latham shale.  And I agree with Tim on the dendrites.

1570884985_PaleontologyofMarbleMtns.pdf

[brotherbbock]

Thanks guys.

 

I was thinking the round one could be Stromatolitic cyanobacterial algal accumulations?

 

 

[Sjfriend]

As for the trilobite, pretty sure it is Olenellus clarki.

 

Yes, 3rd is dendrite. See lots from there.

 

As for 2nd, most of the cyanbacterial is in darker grayish to pinkish very hard rock chunks and lots of it in each chunk of limestone. See attached pic.