Fossils2011

The right piece is an Inoceramid showing the home scars of Pseudoperna congesta (holes where the clams encrusted the Inoceramid). You can tell that it's an Inoceramus shell by looking at the shell in cross-section. You'll see a fibrous cross-section typical of Inoceramid shells. I've had people insist that pieces of Inoceramus are bone, because of this misleading look to the shell. Some times they're beige pieces with suture looking breaks, so it's easy to mistake it. Keith reported: "I also found LOTs of Inoceramus (Platyceramus) platinus (Logan) in the rocks. This is a longer ranging Ino that can be found throughout the Austin Group in the Dallas/Garland/Richardson area (Atco Limestone, Bruceville Marl, Hutchins Chalk). In some places, you can see the cross-sections of countless huge platinus's! This is probably the species in your images with the Pseudoperna congesta (Conrad) home/attachment scars. Speaking of which, I found countless numbers of those oysters at Spring Creek."

Top Right: The Inoceramid is Inoceramus (Cremnoceramus) crassus inconstans (Woods),. The piece below the fossil wood is a piece of calcite with slickenside grooves in it. It fills the joints between the limestone blocks. Probably what happened is that as the blocks faulted or locally settled, the gouged out grooves on either surface. Then, the calcium dissolved in the water (probably as calcium bicarbonate (Ca(HCO3)2) precipitated out as calcite (CaCO3) and filled the cracks. The piece then weathered out, showing the impression of the grooves.

Fossil wood is the most common find on gravel bars in Spring Creek.

AMMONITES

Please help identify this fossil....was located at Beck Branch in Richardson Texas.....a tributary to Rowlett Creek in the same major drainage as Spring Creek. Click on thumbnail to enlarge. Photo taken 2/22/07. Specimen was in rock which had broken off the adjacent cliff face. Looks similar to Parapuzosia americana from Middle Austin Group formation.

This Keith Minor's report on Spring Creek ammonites:

I also saw a couple of ammonite impressions, which may still be there if they haven't eroded away. One impression I was able to refer to Texanites (Plesiotexanites) stangeri densicostatus (Spath), a strongly tuberculate, lowermost Santonian ammonite (~87 mya). I also saw another strongly tuberculate form that looked more like Texanites (Texanites) gallicus Colligon. There really wasn't enough of it to pin a species name on it.

These ammonites indicate an Early Santonian to Late Santonian age for the top of the creek exposure, and also indicate that not only is the Atco exposed there, but the Bruceville and Hutchins fms are also present. If you look at the Geologic Atlas of Texas, Dallas Sheet, these should be the main formations exposed at the creek.

Photo taken July 15, 2006 on lowest formation exposed along Spring Creek close to Maple Ridge Drive.

Above: April 11, 2007: Same fossil after a section split off due to recent high spring flows or possibly vandals....The internal structure is revealed.

Special thanks to Keith Minor for most of the fossil identifications as well as Rocky Manning's identification.

Keith's website is Cretaceous Fossils

Fossil Images submitted by Eric Hansen:

I would like help identifying teeth, bones, shells, and minerals found in the creek bottom and limestone/shale?/mudstone? strata of the SpringCreek Forest Preserve between Shiloh Road and Holford Road in North Garland. I have 9 teeth and approx 40 bones I found in June and July of 2005. The bones are fossilized (no organic material). I have one bone that is 100% organic, so it appears. The largest tooth in length is 3-1/2 inches and looks almost like a tusk! I have a similar one to this but 2-1/2" long. Both appear to be ivory. Then, I have some teeth which are much flater and wider than these. Some with light blue bands. It appears that some of these teeth may have been fused together when the animal was alive. Appears to be 2 or 3 species of animals, or more? Ungulates I presume?

In addition, I have oyster, mussel, scallop-like, and clam shells (some fossils, others not); and some impressive pyrite/pyrite nodules/marcasite specimens, as well as quartz/petrified wood specimens. And I have a worm-like colony fossil perhaps from a prehistoric shallow sea.

Shells and Pyrites:

Teeth:

Bones: