Jdeutsch Posted January 2, 2016 Share Posted January 2, 2016 http://strata.uga.edu/cincy/ is an interesting web site. Lots of information and pictures including a good collection of trilobite photos. My question is regarding the distribution of trilobites in the Cincinnati Ordovician. Are they randomly distributed among the bryozoans, or are there pockets, similar to what one finds in Millard county, UT? 2 Link to comment Share on other sites More sharing options...
erose Posted January 2, 2016 Share Posted January 2, 2016 (edited) Some of the genera can be found almost throughout the entire Cincinnatian sequence while others are limited to shorter ranges. You can find bits and pieces of certain species in many different types of facies or paleoenvironments but complete specimens will be more common in a particular layer. For example for the best Flexicalymenes, the "butter" layers of the Liberty or Waynesville Formations are well known. But you can find pieces and on occasion complete ones in almost every other layer of the entire series. Holland's web site lists known formations which suggest ranges but in fact the presence oif the species may have more to do with the paleoenvironment that was preserved than the age of the layer. Edited January 2, 2016 by erose Link to comment Share on other sites More sharing options...
ZiggieCie Posted January 3, 2016 Share Posted January 3, 2016 (edited) Isatelos PIECES are all over the area. It is amazing how common they were and how rare to find more than pieces now. That is a great site with loads of info. Edited January 3, 2016 by ZiggieCie Link to comment Share on other sites More sharing options...
hrguy54 Posted January 6, 2016 Share Posted January 6, 2016 (edited) Yes to both. I have been going to some a number of sites for years that are teaming with horn corals, numerous kinds of brachs, bryozoans and cephalopods and found just one flexicalemene trilobite at each in the entire time. Then I've gone to a new site and found 5-6. And often lots of Isotelus pieces. I rarely pick up pieces unless they're good sized, which is uncommon. Some spots like a private one in Mt Orab is crawling with flexys and Iso's, and little else. It's a snarge shoot. When you find a good spot it becomes top secret. Edited January 6, 2016 by hrguy54 Link to comment Share on other sites More sharing options...
hrguy54 Posted January 6, 2016 Share Posted January 6, 2016 Hey, I didn't say snarge!!! LOL Link to comment Share on other sites More sharing options...
Wrangellian Posted January 7, 2016 Share Posted January 7, 2016 crapshoot works as one word Link to comment Share on other sites More sharing options...
hrguy54 Posted January 7, 2016 Share Posted January 7, 2016 ......It's a crapshoot. When you find a good spot it becomes top secret. Link to comment Share on other sites More sharing options...
Auspex Posted January 7, 2016 Share Posted January 7, 2016 Hey, I didn't say snarge!!! LOL crapshoot works as one word ......It's a crapshoot. When you find a good spot it becomes top secret. You have discovered my own little amusement with the Forum's word-filter. "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...
California Dave Posted January 25, 2016 Share Posted January 25, 2016 http://strata.uga.edu/cincy/ is an interesting web site. Lots of information and pictures including a good collection of trilobite photos. My question is regarding the distribution of trilobites in the Cincinnati Ordovician. Are they randomly distributed among the bryozoans, or are there pockets, similar to what one finds in Millard county, UT? Some of the Cincinnatian strata is not very good for finding complete trilobites. The Liberty and Waynesville formations of the Richmond Group typically yield the F. retrorsa and Isotelus; the Corryville member of the McMicken formation in the Maysville Group has nice Flexicalymene meeki and also Isotelus, but there are limited known sites. Complete trilobites also occur in lower formations, but are more difficult to find and not as large. There are also discrete zones that are known for rarer trilobites. Cryptolithus and Flexicalymene granulosa are found in the Kope formation, but I am not as keen about that strata. I remember they were never easy to find, my score was 0 complete Cryptolithus, and 1 F. granulosa, and that site no longer exists. When around Cincinnati, concentrate around the 800' elevation level to find the Corryville. Some exposures may exist or may become existent through construction in Butler County just north of Cincinnati. There is a well known locality along the Fairfield Causeway near Brookville Lake in Indiana that is a roadcut and has generally small Flexicalymene retrorsa weathering from the clay/shale layers, along with small Isotelus, all enrolled, that come from the Liberty-Waynesville formational contact zone. As far as bryozoans go, they are not indicative of where good trilobite collecting is in the Cincinnatian. I have only heard of Primaspis trilobites being attached to them. I have never found trilobites associated with the bryozoan layers as you would suspect; while I have observed what I believe you are referring to in Nevada. 4 Link to comment Share on other sites More sharing options...
California Dave Posted January 29, 2016 Share Posted January 29, 2016 (edited) Some of the Cincinnatian strata is not very good for finding complete trilobites. The Liberty and Waynesville formations of the Richmond Group typically yield the F. retrorsa and Isotelus; the Corryville member of the McMicken formation in the Maysville Group has nice Flexicalymene meeki and also Isotelus, but there are limited known sites. Complete trilobites also occur in lower formations, but are more difficult to find and not as large. There are also discrete zones that are known for rarer trilobites. Cryptolithus and Flexicalymene granulosa are found in the Kope formation, but I am not as keen about that strata. I remember they were never easy to find, my score was 0 complete Cryptolithus, and 1 F. granulosa, and that site no longer exists. When around Cincinnati, concentrate around the 800' elevation level to find the Corryville. Some exposures may exist or may become existent through construction in Butler County just north of Cincinnati. There is a well known locality along the Fairfield Causeway near Brookville Lake in Indiana that is a roadcut and has generally small Flexicalymene retrorsa weathering from the clay/shale layers, along with small Isotelus, all enrolled, that come from the Liberty-Waynesville formational contact zone. As far as bryozoans go, they are not indicative of where good trilobite collecting is in the Cincinnatian. I have only heard of Primaspis trilobites being attached to them. I have never found trilobites associated with the bryozoan layers as you would suspect; while I have observed what I believe you are referring to in Nevada. http://strata.uga.edu/cincy/ is a good web site to look at. I enjoyed reviewing that site again. The mention of Cryptolithus occurring throughout the Maysville Group is a remark that I had noticed also years ago when examining the old faunal lists. While the site seems to question these occurrences, my impression is that these reports are probably correct. Another skepticism was cast in a paper recently concerning the range of a Maysville Group brachiopod Cincinnetina (formerly Onniella) multisecta. It was noted that the brachiopod was shown to be present in all formations of that group within the old faunal lists, but its' occurrence was discounted above the lower formations where it is found commonly. However, I had previously noted in a faunal assemblage that I had reconstructed from a Corryville member exposure within an upper formational unit that this brachiopod was present in my Master's thesis dated 1982. It is an extremely rare occurrence, as I only found three of them in a mined exposure, and nowhere else. I have also found a Cryptolithus fragment near the base of the Maysville sequence, which is much higher in section than where it is usually found. If indeed elements such as Cryptolithus were found sporadically in higher formations, and as it is usually found in abundance when it is found, what is indicated by these rare occurrences? Were they originating from another habitat nearby where they should have been plentiful? It is a very puzzling question to me. Edited January 29, 2016 by California Dave Link to comment Share on other sites More sharing options...
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