frankh8147 Posted December 20, 2020 Share Posted December 20, 2020 Hello all! For those not familiar with the Pinna Layer, it is a very small layer representing a very short period of time (weeks to years) after the meteor impact that caused the great extinction of the Cretaceous period. A very thin layer at the bottom of it actually tests positive for Iridium. Last Summer, I was invited to finish off the last remaining outcrops and along with a very small group of other fossil hunters (including other members here), we finished off the last accessible layer - a project which ended just a few weeks ago. It was a group effort and due to the importance of this layer, all of the important finds were donated to MAPS (New Jersey) for future research. That said, it was a complete 'win-win' as we were able to keep a lot of great fossils! In the near future, you will be able to see the donated fossils in 3-D so I figured I would save that for later and show the fossils that now reside in my personal collection. I'll start with my favorites - a Discoscaphites (probable Jerseyensis) I found right on the Iridium layer, and a Discoscaphites Iris cluster. Both prepped by my friend Ralph Johnson. 17 Link to comment Share on other sites More sharing options...
frankh8147 Posted December 20, 2020 Author Share Posted December 20, 2020 Misc. group photographs of finds.. 14 Link to comment Share on other sites More sharing options...
frankh8147 Posted December 20, 2020 Author Share Posted December 20, 2020 I also made sure to take a good amount of that really thin layer that tests for Iridium so it can be tested again in the future (if ever necessary). 12 Link to comment Share on other sites More sharing options...
Fossildude19 Posted December 20, 2020 Share Posted December 20, 2020 This is an amazing collection, Frank! Congratulations on these tremendous finds! 1 Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted December 20, 2020 Share Posted December 20, 2020 Marvelous! Thanks for sharing. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Ludwigia Posted December 20, 2020 Share Posted December 20, 2020 Very interesting to see the few ammonites that survived the impact, although they all disappeared soon afterwards, didn't they? 1 Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
FossilNerd Posted December 20, 2020 Share Posted December 20, 2020 Very nice collection! It must have been exciting to collect in that layer. A geological snapshot of a famous moment in time. 1 The good thing about science is that it's true whether or not you believe in it. -Neil deGrasse Tyson Everyone you will ever meet knows something you don't. -Bill Nye (The Science Guy) Link to comment Share on other sites More sharing options...
digit Posted December 20, 2020 Share Posted December 20, 2020 Very cool to be able to dig in the Cretaceous-Paleogene (K-Pg) boundary and pick up some of the last ammonites. Neither ammonites with belemnites made it through the extinction event with only nautiloids (and the shell-less octopus, squid and cuttlefish) to carry on the cephalopods. I seem to recall an interesting illustrative display in the paleontology section of the Smithsonian Natural History Museum. I recall it graphically showed the pinch-out of the diversity of life forms on either side of the events indicating what few made it through the events. Cheers. -Ken 1 Link to comment Share on other sites More sharing options...
frankh8147 Posted December 20, 2020 Author Share Posted December 20, 2020 2 hours ago, Ludwigia said: Very interesting to see the few ammonites that survived the impact, although they all disappeared soon afterwards, didn't they? 56 minutes ago, digit said: Very cool to be able to dig in the Cretaceous-Paleogene (K-Pg) boundary and pick up some of the last ammonites. Neither ammonites with belemnites made it through the extinction event with only nautiloids (and the shell-less octopus, squid and cuttlefish) to carry on the cephalopods. I seem to recall an interesting illustrative display in the paleontology section of the Smithsonian Natural History Museum. I recall it graphically showed the pinch-out of the diversity of life forms on either side of the events indicating what few made it through the events. Cheers. -Ken Thanks everyone! Yes, this was the end of Ammonites and Eubaculites. It was very exciting for me to be involved in a project like this! Now as to how long they survived, that's debated by people much better than me with Stratigraphy. Estimates range from a few weeks to a few hundred years. I personally don't have an opinion on that one! It's definitely a very short period of time though. 1 Link to comment Share on other sites More sharing options...
digit Posted December 20, 2020 Share Posted December 20, 2020 11 minutes ago, frankh8147 said: It's definitely a very short period of time though. Geologically speaking. Any photos taken at the site? Would be nice to get a feel for where it was you were digging. Cheers. -Ken 1 Link to comment Share on other sites More sharing options...
jeannie55 Posted December 20, 2020 Share Posted December 20, 2020 Are fossils that have iridium on them dangerous? I noticed that the fossils you posted had a yellow cast to them and I have a couple of fossils with yellow on them. I’m being paranoid but I looked iridium up and the scientific language was way beyond my comprehension. 1 Link to comment Share on other sites More sharing options...
digit Posted December 20, 2020 Share Posted December 20, 2020 Nope. Not a radioactive material just an element that is not very common at all in the Earth's crust. Early on in the Earth's formation while everything was still quite molten the iridium that was present tended to bond with iron and sink well below the crustal layer. Because of its natural scarcity but relative abundance in meteorites it makes an important signal of an extraterrestrial impact. Now, yellowcake uranium is entirely a different matter. https://en.wikipedia.org/wiki/Yellowcake Cheers. -Ken 2 Link to comment Share on other sites More sharing options...
Monica Posted December 20, 2020 Share Posted December 20, 2020 What an amazing experience! And what wonderful fossils! Thanks for showing and sharing 1 Link to comment Share on other sites More sharing options...
jpc Posted December 20, 2020 Share Posted December 20, 2020 excedllent stuff. I am curious as to what you mean by "finish off the last remaining outcrops " 1 Link to comment Share on other sites More sharing options...
historianmichael Posted December 20, 2020 Share Posted December 20, 2020 What a unique experience and some incredible finds! If you were able to keep those, I am excited to see what made it to MAPS! 1 Follow me on Instagram (@fossil_mike) to check out my personal collection of fossils collected and acquired over more than 15 years of fossil hunting! Link to comment Share on other sites More sharing options...
Jeffrey P Posted December 20, 2020 Share Posted December 20, 2020 Wow Frank! You really collected some excellent specimens there. I especially love the Discoscaphites, but that pinna clam and the echinoid are also truly marvelous. It was a pleasure to be there with you and Ralph on a couple of those occasions. I am in the process of creating my own display of Pinna Layer specimens. P.S.- The locations of these KT boundary sites in Central New Jersey are a carefully guarded secret. It was a special privilege to be allowed to collect there. 2 Link to comment Share on other sites More sharing options...
Jeffrey P Posted December 20, 2020 Share Posted December 20, 2020 28 minutes ago, historianmichael said: What a unique experience and some incredible finds! If you were able to keep those, I am excited to see what made it to MAPS! Here's a photo of some of the Pinna Layer specimens in the MAPS collection. 3 Link to comment Share on other sites More sharing options...
historianmichael Posted December 20, 2020 Share Posted December 20, 2020 21 minutes ago, Jeffrey P said: Here's a photo of some of the Pinna Layer specimens in the MAPS collection. Thank you for sharing! Those are absolutely incredible. Some of those baculites and ammonites are huge! Follow me on Instagram (@fossil_mike) to check out my personal collection of fossils collected and acquired over more than 15 years of fossil hunting! Link to comment Share on other sites More sharing options...
Creek - Don Posted December 20, 2020 Share Posted December 20, 2020 4 hours ago, Ludwigia said: Very interesting to see the few ammonites that survived the impact, although they all disappeared soon afterwards, didn't they? I just read the paper published on Pinna layer of New Jersey https://www.app.pan.pl/archive/published/app57/app20110068.pdf It seems some species may have been survived decades or even longer after the extinction event. 1 Link to comment Share on other sites More sharing options...
Al Dente Posted December 20, 2020 Share Posted December 20, 2020 7 hours ago, frankh8147 said: For those not familiar with the Pinna Layer, it is a very small layer representing a very short period of time (weeks to years) after the meteor impact that caused the great extinction of the Cretaceous period. A very thin layer at the bottom of it actually tests positive for Iridium. I think it is unfortunate that the iridium anomaly was used as a marker for the end of the Cretaceous instead of using index fossils. There is some evidence that the iridium can migrate in the strat section. There are some sites in NJ where the iridium occurs below the tektites and shocked minerals while in Texas the iridium can be many feet above the tektite layer. I can imagine a scenario where a Paleocene ammonite born in New Jersey can have offspring that swim to Texas and die in the Cretaceous. 6 Link to comment Share on other sites More sharing options...
frankh8147 Posted December 20, 2020 Author Share Posted December 20, 2020 @Al Dente Yep! We consider the Pinna layer to be part of the Cretaceous with the Lower Hornerstown being the very beginning of the Paleocene. Link to comment Share on other sites More sharing options...
frankh8147 Posted December 20, 2020 Author Share Posted December 20, 2020 5 hours ago, Jeffrey P said: Wow Frank! You really collected some excellent specimens there. I especially love the Discoscaphites, but that pinna clam and the echinoid are also truly marvelous. It was a pleasure to be there with you and Ralph on a couple of those occasions. I am in the process of creating my own display of Pinna Layer specimens. P.S.- The locations of these KT boundary sites in Central New Jersey are a carefully guarded secret. It was a special privilege to be allowed to collect there. Good times! We have some good trips coming up too! Link to comment Share on other sites More sharing options...
frankh8147 Posted December 21, 2020 Author Share Posted December 21, 2020 20 hours ago, digit said: Geologically speaking. Any photos taken at the site? Would be nice to get a feel for where it was you were digging. Cheers. -Ken Im not sure. Honestly, I never bring my phone or camera with me on a dig, it's just my time to 'get away' but I'll see if anyone took any. Link to comment Share on other sites More sharing options...
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