surfergirlatx Posted February 4, 2012 Share Posted February 4, 2012 (edited) Greetings TFF! Yesterday I was able to go on another hunt in the Austin Chalk Central Texas. Several clams Inoceramus (Cremnoceramus) and nice shell fragments...then I found this piece in question shown below. I have never seen anything like it before on my hunts. Due to the nature of the shape, I was hoping that someone here has seen this type of fossil before. #1. Front #2. Side #3. Back - note the iron deposit....also have not seen this on a fossil before. Any thoughts, comments or suggestions would be greatly appreciated! Thank you in advance for your time, Kim Edited February 24, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
Foshunter Posted February 4, 2012 Share Posted February 4, 2012 Don't have a clue, glad you aren't afraid of spiders in pix #1 Grow Old Kicking And Screaming !!"Don't Tread On Me" Link to comment Share on other sites More sharing options...
Bill Posted February 4, 2012 Share Posted February 4, 2012 Black spider on an ammonite chamber. KOF, Bill. Welcome to the forum, all new members www.ukfossils check it out. Link to comment Share on other sites More sharing options...
fishguy Posted February 4, 2012 Share Posted February 4, 2012 an ammonite chamber but not enough to identify Link to comment Share on other sites More sharing options...
Indy Posted February 4, 2012 Share Posted February 4, 2012 Spider ???? Oh, yea...I see it now Obviously, Kim isn't Little Miss Muffet Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 4, 2012 Author Share Posted February 4, 2012 (edited) Thanks for pointing out the spider.....I honestly didnt even notice it until I began to view the pictures. oops! So now I have learned that when taking home fossils...and there is webbing on the piece...remove webbing prior to bringing piece inside.....live and learn Edited February 4, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
Foshunter Posted February 4, 2012 Share Posted February 4, 2012 Surfergirl----Beware what you bring home---Tom Grow Old Kicking And Screaming !!"Don't Tread On Me" Link to comment Share on other sites More sharing options...
JohnJ Posted February 4, 2012 Share Posted February 4, 2012 Congrats on your finds. I agree with the others regarding the cast of the ammonite section. I hope you find a whole one soon. I am confused as to what you mean by "Austin Chalk (San Vicente) Group" as relates to the Austin Group or Division? I'm not familiar with any member or formation in the Austin Chalk known by that name. There is a San Vicente Member of the Boquillas Formation in the Big Bend area of Texas that correlates to part of the Central Texas Austin Division, but it is not recognized as part of the stratigraphic column in the Jarrell area. The human mind has the ability to believe anything is true. - JJ Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 4, 2012 Author Share Posted February 4, 2012 Congrats on your finds. I agree with the others regarding the cast of the ammonite section. I hope you find a whole one soon. I am confused as to what you mean by "Austin Chalk (San Vicente) Group" as relates to the Austin Group or Division? I'm not familiar with any member or formation in the Austin Chalk known by that name. There is a San Vicente Member of the Boquillas Formation in the Big Bend area of Texas that correlates to part of the Central Texas Austin Division, but it is not recognized as part of the stratigraphic column in the Jarrell area. Very exciting indeed to find a ammonite section that looks like this one!!! Hoping to find a better one soon! I only said San Vicente Group as that is what the HGMS book says for the Austin Chalk??? "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
JohnJ Posted February 5, 2012 Share Posted February 5, 2012 THIS has some good geologic info for that area. The human mind has the ability to believe anything is true. - JJ Link to comment Share on other sites More sharing options...
Indy Posted February 5, 2012 Share Posted February 5, 2012 Austin Chalk ... Living in Missouri and never hunted the area...I went to Wiki The Austin Chalk is an upper Cretaceous geologic formation in the Gulf Coast region of the United States. It is named after type section outcrops near Austin, Texas. The formation is made up of chalk and marl. Chalk and Marl ... that's soft matrix. Correct me if I'm wrong...Fossils in this soft matrix should be super easy to prepare and melt away when using a micro abrasive unit (air brush) Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
Missourian Posted February 5, 2012 Share Posted February 5, 2012 Austin Chalk, Austin Group, San Vicente Group, San Vicente Member. Oy..... There really needs to be a central clearinghouse for stratigraphic nomenclature and correlation. Context is critical. Link to comment Share on other sites More sharing options...
Indy Posted February 5, 2012 Share Posted February 5, 2012 Noticed what what appears to be traces where worm tubes were attached Ammonite living chamber Not being an ammonite aficionado...are we looking at a view of the orifice? Would be interesting to see some comparable images (free of matrix) Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 6, 2012 Author Share Posted February 6, 2012 (edited) Austin Chalk ... Living in Missouri and never hunted the area...I went to Wiki The Austin Chalk is an upper Cretaceous geologic formation in the Gulf Coast region of the United States. It is named after type section outcrops near Austin, Texas. The formation is made up of chalk and marl. Chalk and Marl ... that's soft matrix. Correct me if I'm wrong...Fossils in this soft matrix should be super easy to prepare and melt away when using a micro abrasive unit (air brush) Indy, obviously I am NO expert, but if I HAD to describe the matrix, I would say Chalk....The stone is white in color, the fossils are a tanish color, but only found once the rock is broke open. You hardly need a rock hammer as the matrix breaks so very easily. I am about to post my hunting trip in the Kau (Austin Chalk) and hopefully that can determine what matrix we are in. Being that its Austin Chalk.....I am going with Chalk Indy, I am a toothbrush and water kinda prep girl....not one for the micro abrasive unit (air brush) hahahahha Edited February 7, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 6, 2012 Author Share Posted February 6, 2012 THIS has some good geologic info for that area. JohnJ. Thank you for this excellent data source! This will help me greatly!!!!! "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
Boneman007 Posted February 6, 2012 Share Posted February 6, 2012 The Austin Chalk in Dallas is harder than my ex-wife's attitude.... Not soft at all. My diamond saw blade has a heck of a time with it. There is a layer that produces very nice, large ammonites. Since you found that chunk, I would concentrate on that geologic strata. You should find more ammonites. Link to comment Share on other sites More sharing options...
Indy Posted February 6, 2012 Share Posted February 6, 2012 The Austin Chalk in Dallas is harder than my ex-wife's attitude Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 7, 2012 Author Share Posted February 7, 2012 (edited) Hummmm.......any chance we could be looking at a Rhombopora lepidodendroides??? Some bryozoans built colonies that grew from the seafloor in branching structures; these fossils look like something like twigs. Almost all the fossils are fragments of colonies; only rarely is an entire colony preserved. Source: http://www.kgs.ku.ed...s/bryozoan.html Could someone maybe show me an example of an ammonite chamber? The only ones I am finding do not branch out like my piece does? Rhombopora lepidodendroides vs. Ammonite chamber Source: http://en.wikipedia....wiki/Ammonoidea I am the LAST person to every say a bryozoan but due to its branching...I am just confused. Could I ask for a bit of a more detailed explination or perhaps to see a ammonite chamber that branches out simlar to the piece I found? I am TOTALLY open to constructive criticism and I promise you cant hurt my feelings. Edited February 7, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 7, 2012 Author Share Posted February 7, 2012 (edited) The Austin Chalk in Dallas is harder than my ex-wife's attitude.... Not soft at all. My diamond saw blade has a heck of a time with it. There is a layer that produces very nice, large ammonites. Since you found that chunk, I would concentrate on that geologic strata. You should find more ammonites. Well Boneman007.....remind me to avoid the ex-wife kidding The matrix here must not be "Austin Chalk"...I am leaning toward Marl...I only say this because its soooo soft. When wet it turns to mud, and you dont even need a rock hammer to break apart the rocks...you can simply pull the matrix apart with your hands....which can also be bad as I am destroying so many fossils.....live and learn. Thank you for helping me to better understand the geologic strata better. Thank you in advance for your time and kindness! Kim Edited February 7, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
Auspex Posted February 7, 2012 Share Posted February 7, 2012 With your fossil, you are looking, not at a cross section, but straight-on at the surface of a chamber divider. Those convolutions are what create the sutures we see, where the septa meet the shell's walls. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 7, 2012 Author Share Posted February 7, 2012 (edited) With your fossil, you are looking, not at a cross section, but straight-on at the surface of a chamber divider. Those convolutions are what create the sutures we see, where the septa meet the shell's walls. Thank you Auspex, that does help to explain it much better. I genuinely appreciate your help! By any chance are there any pictures or literature that can better help me to visualize this? Kim Edited February 7, 2012 by surfergirlatx "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
jpc Posted February 7, 2012 Share Posted February 7, 2012 I totally agree with ole auspex on this one. Not bad for a bird guy... (Ok, he does know a lot about all sorts of fossils). Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 7, 2012 Author Share Posted February 7, 2012 With your fossil, you are looking, not at a cross section, but straight-on at the surface of a chamber divider. Those convolutions are what create the sutures we see, where the septa meet the shell's walls. Ok...I think I am starting to understand...I found this that somewhat explains the branching I am seeing: Source: http://www.ukfossils.co.uk/guides/ammonites.html Am I getting closer? Again, sorry for all my questions and Thank you for you continued assistance. Kim "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
surfergirlatx Posted February 7, 2012 Author Share Posted February 7, 2012 I totally agree with ole auspex on this one. Not bad for a bird guy... (Ok, he does know a lot about all sorts of fossils). Thanks JPC...I just was having a hard time trying to visualize the ammonite chamber from such a different perspective, but its all making since now. Sorry to be such a pain in a rear "The road to success is always under construction." Author Unknown. Link to comment Share on other sites More sharing options...
jpc Posted February 7, 2012 Share Posted February 7, 2012 Bingo... that last picture you showed is exactly what you have found, only the preservation is different and you don't have the nacre like that specimen has. But it looks like it has helped you understand what you have. Nice find, so says I who rarely collects in TX. Link to comment Share on other sites More sharing options...
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