Coral Identification (Gila County, AZ)

[FossilAZ]

Hi All, any thoughts on these specimens?  Location is Roberts Mesa in Gila County, Arizona.  (east of Payson)

The red coral-like stems were found loosely on the ground very near the red trunk and gray matrix pieces.  So I’m making some assumptions that the two are related as they were found maybe within 100 meters of one another.  And the red stems above looked similar to the red trunks below of course.

My first thoughts are some sort of coral but could they be a sponge instead?   I’m assuming all are Naco Formation?

Comments welcome.

Photo size reference is in inches.

cheers, DJ

 

[FossilDAWG]

I don't see any obvious corals in this lot.  Chert nodules are common in the Naco and other limestone formations in that area.  Some may be silicified sponges, but I'm not sure.  @DPS Ammonite is very knowledgeable about Arizona fossils, hopefully he will stop by and offer an opinion.

 

Don

[FossilAZ]

Thanks Don.  I realized I should have probably labeled these so I’m attaching some labeled pictures.  Yeh, I could see where maybe these are sponges too.  The Stems (#1) were found very close to the Matrix (#2), maybe less than 100 meters on average.  In some cases the Stems were very close maybe only a few meters away from some of the chunks of the Matrix.  So I think the two are related.  The Stems were present on the ground probably in an area maybe 100 x 100 meters, so over a fairly sizeable area.  My thoughts are the Stems probably broke away a long time ago away from pieces of Matrix as the Mogollon Rim rose up and/or with errosion, etc.  But it’s anyone’s guess.  Interesting stuff for sure.

 

DJ

 

 

[DPS Ammonite]

Welcome to the Forum.

 

Most  are Naco Fm. decapod burrows burrows that are locally common south of FR 29 and east of Tonto Creek. Sponges occur in the area. Show me a detail of circled rocks; they may be sponges if spicules are present.

 

Some of the “stems” could be “wood”. In person viewing could help.

 

Are you a member of the Southwest Paleontological Society or the Mineralogical Society of Arizona? I lead fossil trips for both groups.

 

I will be happy to look at your fossils. I will be displaying my fossils at the Pinal Geology Museum on March 12th. https://www.pinalgeologymuseum.org