Fossil coral ?

[Mre9065]

Hello, first post here. Reside near Houston, Tx and found this in gravel bed on San Jacinto River near conroe, tx.   From what I can gather I believe its fossilized coral. However, the only images I've been able to find online that closely resemble it have all been labeled as Indonesian fossil coral. Was hoping someone could help to identify it, and also shed some light on how common or uncommon it is to find this type of coral in this general area of southeast texas.  Any help and info is much appreciated!  And thanks for looking!

[FranzBernhard]

Welcome to TFF from Austria!

Wow, that´s a really nice colonial coral!! Exceptionally well preserved!

I don´t know if such corals occur in Texas, but others may know:

@grandpa, @JohnJ, @erose

Franz Bernhard

[Mre9065]

4 minutes ago, FranzBernhard said:

Welcome to TFF from Austria!

Wow, that´s a really nice colonial coral!! Exceptionally well preserved!

I don´t know if such corals occurs in Texas, but others may know:

@grandpa, @JohnJ, @erose

Franz Bernhard

Thank you for your reply and kind words!  

[Fossildude19]

Beautiful coral! 

 

[El_Hueso]

That is jaw dropping gorgeous.

[Rockwood]

I think it's safe to say it's a scleractinian coral.

[Mre9065]

Thanks for the kind words everyone!    

[Mark Kmiecik]

Very nice coral. If you look where you found that one there should be many more. Coral fossils are common all over the world. Think about it. Every continent, every island is surrounded by shallower waters almost all of which have coral. So any land that was underwater at any time in the last 500 million years, which is a whole lot of places, will have fossil coral because they have been present in oceans since then all the way to today. That's a lot of coral and a lot of it became fossilized. However not all are as nice as that one.

[Rockwood]

20 minutes ago, Mark Kmiecik said:

So any land that was underwater at any time in the last 500 million years, which is a whole lot of places, will have fossil coral because they have been present in oceans since then all the way to today. 

Early Triassic ?

[Mark Kmiecik]

2 minutes ago, Rockwood said:

Early Triassic ?

Coral reefs can be massive structures, stretching hundreds of miles. The Great Barrier Reef in northern Australia can be seen from space. The oldest coral fossils are over 500 million years old. The earliest forms were different from those we see today and they died out 225 million years ago.

Corals - Oxford University Museum of Natural History

 

https://www.oum.ox.ac.uk › thezone › fossils › inverts › coral

 

Cambrian, according to this.

[Rockwood]

2 hours ago, Mark Kmiecik said:

Coral reefs can be massive structures, stretching hundreds of miles. The Great Barrier Reef in northern Australia can be seen from space. The oldest coral fossils are over 500 million years old. The earliest forms were different from those we see today and they died out 225 million years ago.

Corals - Oxford University Museum of Natural History

 

https://www.oum.ox.ac.uk › thezone › fossils › inverts › coral

 

Cambrian, according to this.

Not this one. And not any one for a stretch in the "early Triassic".

[grandpa]

4 hours ago, Rockwood said:

Early Triassic ?

See, that's where I'm confused.  The county in which it was found (Montgomery Co.) and the river in which it was found (San Jacinto R.) are Tertiary/Quaternary age deposits (Miocene - Pleistocene).  I don't know of a coral from this age that matches this coral.  Maybe some coral expert or Tertiary/Quaternary expert recognizes it and can chime in.

[FranzBernhard]

3 hours ago, grandpa said:

I don't know of a coral from this age that matches this coral.

Now its becoming interesting!

 

@Mre9065stated that:

14 hours ago, Mre9065 said:

However, the only images I've been able to find online that closely resemble it have all been labeled as Indonesian fossil coral.

He found it in a gravel bed of a Texan river: 

14 hours ago, Mre9065 said:

in gravel bed on San Jacinto River near conroe, tx

"Indonesien fossil coral" is used for cabs etc, and some of the items match his specimen quite well. I am wondering, if a piece of rough was (accidentally) dropped in the river?

 

Lets ask @HansTheLoser for an expert opinion. Thanks, Hans!

Franz Bernhard

[Rockwood]

4 hours ago, grandpa said:

See, that's where I'm confused.  The county in which it was found (Montgomery Co.) and the river in which it was found (San Jacinto R.) are Tertiary/Quaternary age deposits (Miocene - Pleistocene).  I don't know of a coral from this age that matches this coral.  Maybe some coral expert or Tertiary/Quaternary expert recognizes it and can chime in.

Early Triassic is just the time when there were no corals at all for a while. The Miocene -Pleistocene shouldn't be a problem temporally.

[jkfoam]

Montgomery County, Texas and particularly the San Jacinto River has  numerous alluvial gravel deposits and some are mined or have been mined for the sand and gravel.  The gravels contain jaspers, petrified wood and other quartz based rocks.  There is no telling where their origin was.  West, North and Northeast of Montgomery County are marine Eocene deposits that have corals but none have agatized corals as the specimen in question appears to me to be.  Further West and North are Cretaceous formations some of which have a few corals (even Septastrea, which appears similar to the specimen in question).  Years ago while hunting rabbits with Beagle dogs in the San Jacinto River bottom (witch is now below Lake Conroe) I picked up a piece of gravel that contained a solitary rugose coral fragment.  No telling how far that paleozoic coral had to travel to wind up where it did.

 

I guess my point is that the origin of  rocks from alluvial deposits may never be known.  That said, from a lapidary perspective I would have loved to have found that specimen.

 

Jim

[Mre9065]

Wow, thank you to everyone for replying to this thread and sharing your knowledge!  I've learned quite a bit from this and all my questions have been answered and much more sufficiently than expected!

   I can spend hours upon hours rockhounding the gravel bars of San Jacinto river but never expected something like this. But am happy to have found this piece, even if it's the only one I ever found.   Thank you again everyone for taking the time to read and comment on this thread!

[DPS Ammonite]

There are reports of silicified Paleozoic corals in Texas found in areas that now only contain Cretaceous rocks. Over millions of years gravel can get moved a long distance and can get reworked many times. There probably was a river that drained areas with Paleozoic rocks that has long since changed course.

 

http://www.thefossilforum.com/index.php?/topic/95363-unknown-bit-from-cretaceous-texas-fredericksburg-group/&tab=comments#comment-1051893

 

 

[Pippa]

Congrats! What a great find.  That's a georgeous specimen. No matter what exactly it is. 

 

I'm 

 

[Mark Kmiecik]

19 hours ago, Rockwood said:

Not this one. And not any one for a stretch in the "early Triassic".

I didn't say anything about this one. Only that corals have existed for a long time. You questioned whether corals existed in the Early Triassic. They did.

[Rockwood]

3 hours ago, DPS Ammonite said:

There are reports of silicified Paleozoic corals in Texas found in areas that now only contain Cretaceous rocks. Over millions of years gravel can get moved a long distance and can get reworked many times. There probably was a river that drained areas with Paleozoic rocks that has long since changed course.

You are arguing that the septal insertion pattern looks rugose ?

[Rockwood]

1 hour ago, Mark Kmiecik said:

I didn't say anything about this one. Only that corals have existed for a long time. You questioned whether corals existed in the Early Triassic. They did.

You are arguing that scleractininan coral evolved before the paloes. kicked off ?

[Mark Kmiecik]

Just now, Rockwood said:

You are arguing that scleractininan coral evolved before the paloes. kicked off ?

I didn't mention any order, family, genus or species. I only said that corals have been around for a very long time in vast quantities and are therefore abundant in the fossil record. I made a general statement that corals were widespread both in time and area, but you quoted my post and I thought you had implied that corals, in general, had not existed prior to the early Triassic. We have thoroughly misunderstood each other I'm afraid. I agree that sclerictinian corals would not predate that time period, but others did. I apologize for any confusion.

[DPS Ammonite]

 

40 minutes ago, Rockwood said:

You are arguing that the septal insertion pattern looks rugose ?

I do not know if this coral is Paleozoic or not. I was pointing out that probable Paleozoic corals occur in Texas gravels far away from from any likely source. The take away is that the source of a fossil may no longer exist in the watershed of the river that it was found in. Over millions of years formations erode away, rivers change course and gravels are redeposited. Recently deposited gravel is not composed solely of recently formed rocks.

 

A coral expert should be able to tell if the coral is possibly Paleozoic. Below is an enlargement of the coral. Rugose, tabulate or scleractinian?

[Rockwood]

@TqB is usually pretty good at this sort of thing.

[Rockwood]

30 minutes ago, Mark Kmiecik said:

I apologize for any confusion.

That's okay, not being a Mainer you wouldn't be used to meaningless arguments being condensed to one word.