What Is It? Triassic Footprint?

[nubrandon]

Hi,

I picked this up from an estate but Im not 100% on what it is, or even if its anything. I was told it was a Triassic period footprint from Utah. This may be a dumb question but if it is, why does it protrude from the stone rather than sink in? The foot print is supposed to be on the upper right over the ridge. Any help would be nice. Thanks in advance.

[flyguy784]

Picture is not that good but it looks like it could be. I'm not sure about it being found in Utah however. When you split a rock and it opens up to reveal a fossil like this, there will be a positive and a negative component to the fossil. Called cast and mold. The piece you have is basically a cast of the material that infilled the track,then hardened over time.

I looked briefly this morning in some of my reference material and have found no mention of tracks being found in that state. Do a search for that states geologic survey to see if there are any Triassic formations that have produced tracks. I'll dig a little deeper after work.

Edited February 2, 2010 by flyguy784

[va paleo]

http://geology.utah.gov/utahgeo/dinofossil/dinoage.htm it says on thier that Triassic dinosaurs have not yet been found in Utah. Late Triassic rocks known as the Chinle Formation are exposed throughout southern and eastern Utah However fossil skeletons of other animals are known from Utah and it is only a matter of time before Utah's first Triassic dinosaur is discovered.

[va paleo]

i will talk 2 James Kirkland, he the uath State Paleontologist and a godd friend a show him the pics if that ok and see if he knows for you

[nubrandon]

Wow guys, thanks for all the help! Here are a few better photos.

[Phoenixflood]

Yes, you definitely have a cast of a dino footprint.

Here is a link to some info that may shed some light on its location. Hope this helps.

http://www.nature.nps.gov/geology/paleontology/pub/grd2/gsa11.htm

[nubrandon]

Any guesses on the creature? Grallator? Coelophysis? Its about 3 3/4" from toe to toe & 4 1/2" from front to back. Again, thanks for all the help.

[va paleo]

it a meateating dinosaur for sure i emailed my friend Andrew R C Milner he a Paleontologist at the St. George Dinosaur Discovery Site at Johnson Farm is home to exceptionally well-preserved dinosaur tracks and one of the worlds best at dinosaur tracks i think he going 2 join here and id it if not he weill tell me 2 send pics but eather way you will get a id soon

[Nicholas]

Could you spray the surface of the rock with water or wet it, it tends to define prints much better. It may help with the id process.

[Phoenixflood]

Could you spray the surface of the rock with water or wet it, it tends to define prints much better. It may help with the id process.

Yes, or put baby powder around the outline of the print. It will come off easy too.

Most of the footprints like this are give the general label grallator, but it very well could be Coelophysis.

[flyguy784]

Yes, you definitely have a cast of a dino footprint.

Here is a link to some info that may shed some light on its location. Hope this helps.

http://www.nature.nps.gov/geology/paleontology/pub/grd2/gsa11.htm

Good post, wasn't aware Chinle formation was in Utah. Thanks.

[va paleo]

It's a poorly preserved Grallator natural cast. Looks like it's from what we call the "Top Surface Tracksite" at the St. George Dinosaur Discovery Site at Johnson Farm. Actually I'm 99% positive on that, meaning it from the lowermost Whitmore Point Member, Moenave Formation. Lower Jurassic (Hettangian; 198-195 MYA). Hope it was collected legally, but I kind of doubt it since all outcrops at our site are protected. Not too big a deal though since we have over 3500 individual Grallator tracks and counting in our collection.

that info form Andrew R C Milner

[nubrandon]

Ok, here are some pics after I sprayed water on it. I dont have any powder though.

[Auspex]

Any guesses on the creature? Grallator? Coelophysis? Its about 3 3/4" from toe to toe & 4 1/2" from front to back. Again, thanks for all the help.

Bear in mind that the "species" names given to tracks are not the name of the critter that made them (which is seldom known). Trace fossils ("ichnofossils") have their own form-names.