grommit Posted April 23, 2008 Share Posted April 23, 2008 Can anybody suggest a good guide/list to what is in the different fossil layers? On the site, I found some nice maps of the North Tex area that someone (I think LanceHall) made, color coded to the different layers. Austin Chalk, Main Street, etc.... I now need a reference that says what I can find in those layers, so I can target my searching. I am not picky, but am assuming some layers are pretty blank. THanks, Grommit (Chris). Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted April 23, 2008 Share Posted April 23, 2008 I hate to say it, but the best faunal lists I can think of are in the TX Cretaceous ammonite and echinoid references by Akers and Akers available from HGMS.org. For better images on a small subset of these species, see Finsley's book Field Guide to the Fossils of Texas. For still fewer but better images visit cretaceousfossils.com. For Cretaceous shark teeth pick up Welton and Farish's book. The is no single, convenient repository of hi quality images of all ammonites, all echinoids, all shark teeth, or all crabs from TX that I know of. Available references generally point you to formations, but what you really need to know are specific zones for specific fossils within each formation. For that level of detail you need to pick up original references with strat diagrams. This takes some legwork and expense at your end to pull together as you'll basically need to build your own personal paleo library. With experience you'll be able to come up with site info not found in literature. That my friend is the rainbow with the pot of gold you are looking for. Unfortunately there are no shortcuts I know of in getting there. If there were I would have followed them 5 years ago when I was in your shoes. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
Roger Posted April 23, 2008 Share Posted April 23, 2008 Can anybody suggest a good guide/list to what is in the different fossil layers?On the site, I found some nice maps of the North Tex area that someone (I think LanceHall) made, color coded to the different layers. Austin Chalk, Main Street, etc.... I now need a reference that says what I can find in those layers, so I can target my searching. I am not picky, but am assuming some layers are pretty blank. THanks, Grommit (Chris). Chris First you found an excellent site in Lance Hall's. . . his maps are great and very helpful in finding your way around in the geology. . . remember that those maps are SURFACE geology. Therefore if you find a road cut or a deep creek with an exposure you are liable to get into the next lower formation. References are as close as your computer and a bit of research. The Texas Bureau of Economic Geology has done several reports over the years. One of these reports is known as "The Geology of Tarrant County". I suggest you either Google or Yahoo Web search the title and you'll be directed to a website where you can download a 132 page .pdf report. In this report you'll find all sorts of information - some not so necessary for the fossil hunter but other parts quite helpful. The problem with the reports from T BEG is that some were done back in the early 1900s and some of the sites they reference are long since built over or gone. (btw - there are similar reports for most if not all of the counties in TX) Also you can check out this website http://txaps.proboards107.com/index.cgi. There are several reference sections where you can get the names of articles specific to our local area. Several of the local collectors here in the DFW area are on that site and we trade a lot of information there. What I think is interesting about fossil collecting is that it is like a detective story. Sometimes you'll stop and find a location and you can not be "sure" as to where you are located geologically speaking. Therefore you collect fossils - hopefully several different ones and then come home and go to your references. Those references will tell you (sometimes) the geologic range of various fossils. Therefore from your fossils, you build a case for what geologic formation you were hunting in. This is what happened to me when I located the Bursey road site. I had to collect several fossils and from them determine where I was. Just a mile to the east the red sandstone of the Woodbine formation is prevalent but I also could have been in a Paw Paw exposure. The maps I had really didn't specify my location clearly. I collected, researched, asked friends what they thought, took pictures, and finally determined that I was in the Grayson formation. Clearly getting the book "A Field Guide to Texas Fossils" by Chuck Finsley is your next move. Take care and good hunting. Roger Link to comment Share on other sites More sharing options...
grommit Posted April 23, 2008 Author Share Posted April 23, 2008 >>Clearly getting the book "A Field Guide to Texas Fossils" by Chuck Finsley is your next move. Thanks for both replies. I bought the book today. Will read. I actually didn't want the whole pot of gold. I was interested in something like: Echinoids generally found in : Mainstreet, grayson, Ammonites generally found in : duck creek Shark teeth generally found in: ? etc... unless no such generality can be made. Are all formations good for finding something? What I am trying to avoid is searching formations with nothing in them. Link to comment Share on other sites More sharing options...
Roger Posted April 24, 2008 Share Posted April 24, 2008 <<What I am trying to avoid is searching formations with nothing in them.>> amen Chris - that is what we all are trying to do<grin>!! Just remember somedays you get the bear - other days the bear gets you!!! <<unless no such generality can be made. Are all formations good for finding something?>> Generally - yes, but sometimes what is there can be very small. . . for example the other day we were in a Paw Paw formation in North Fort Worth off of Beach Street and there is a very small floating crinoid that you have to be on hands and knees (butt up, head down) in order to find - you just can't walk along and see them. On the other hand - if you travel up Davis Blvd from I-820 you'll see really nice exposures along the west side of the road. . . sort of a reddish sandstone. . . that's Woodbine and there is nothing there that I have been able to find. . . but as Dan said it is also the same Woodbine formation that has given us one of the earliest hadrosaurs (near DFW airport) - so go figure. . . I don't mean to discourage you - because one "bad" day in the field is better than a "good" day at work!!! There is no easy way - like Dan said if there was we all would have been there a long time ago. Joining the DPS (Dallas Paleo Society) is good and it is a good time to do so. They are getting ready to do some field trips this summer. What they plan to do is have the monthly meeting's talk focus on a particular fossil formation or site; then they will have a field trip to the site within a couple of weeks after the meeting. Sort of like a class lecture follwed by a field lab. It would be very instructive for you and hey - even for me. Also at the meeting they have several books for sale - Roger Farish's Shark book, as well as The North Sulphur River Field guide and Mark McKenzie's book on Pennsylvania Fossils in North TX. . . all in all - bring your check book<smile>!! So hang in there - buddy. . . just a little elbow grease on the computer and a bit of reading and research. Hope to see you at the meeting on May 14th (I'm the guy wearing the cowboy hat)!!. Roger Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted April 24, 2008 Share Posted April 24, 2008 Grommit Your easiest paydirt for ammonites and echinoids will come from the Goodland, Duck Creek, and Fort Worth formations. You'll find Oxytropidoceras, Hemiaster whitei, Engonoceras, etc. in the Kgd and Macraster, Holaster, Eopachydiscus, and Mortoniceras in the Kdcfw. This ought to keep you busy for a while amassing a pile of Texas index fossils. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
Recommended Posts