Leptaena Brachiopod with Cornulites Worm Tubes

These images are of a Leptaena waldronensis? brachiopod that has two Cornulites sp. worm tubes attached. It somewhat rare to find the Cornulites worm tubes on fossils found in the Clark County, Indiana Waldron Shale. These fossils date to the Silurian Period (425-420 million years ago).

I encountered this fossil while volunteering at Earth Discovery Day at the Falls of the Ohio State Park in Clarksville, Indiana, USA. It is a good event to help the general public to learn about fossils and minerals found on our planet. The specimen shown was found by visitor on August 24, 2013.

Earth Discovery Day - August 2013

Today was Earth Discovery Day at the Falls of the Ohio State Park in Clarksville, Indiana. It is an event that focuses on educational activities for public. I have been volunteering over the last several years and it is a good feeling helping young students learn more about the mineral world around them while teaching about the fossil world of the past. Even though I have been really busy teaching, it is good to help out at an event like this.

The fossil pile was sparse in finds this year but the mineral pile while very dusty was a mountain of exploration for those willing to search for buried mineral treasure. The material is from a fluorite processing mill in southern Illinois that processed minerals from that area. Normally one sees four types of minerals: fluorite, barite, calcite, and sphalerite. The fluorite is usually purple, yellow or clear. Occasionally, green and blue fluorite will be found. A child found a nice fluorite cube corner shown in the first picture above. It has some nice purple phantom cubes that show through when held up to a light source.

Another child found a greenish-blue fluorite fragment while another found several aqua blue fluorite pieces. My challenge to visitors is to find pieces like this and usually about 4-6 specimens are found during my volunteer shift.

I was also told some material from China was processed there as well. So I am not sure what that might look like. A red or crimson colored rock was being found this year that was not seen in past years. It might be something from China. It is thought to be some type of reddish fluorite.

Fossils found were a number of brachiopods, corals, and snails from the Devonian fossil pile. The Silurian pile was being a bit more stingy. It did yield some nice brachiopods, a trilobite fragment, and a cephalopod fossil. Silurian Period Waldron Shale fossils are as shown: probably the tail (pygidium) of an Arctinurus sp. trilobite (I think it is upside down), next a fragment of a shell of a Dawsonoceras cephalopod, third is the index fossil of the Waldron Shale Eucalyptocrinus crassus crinoid calyx cup, and last an uncompressed Leptaena sp. brachiopod that has Cornulites sp. worm tubes on it.

Earth Discovery Day 2012

The Falls of the Ohio State Park (Clarksville, Indiana, USA) hosted a geology education day with lots of activities the general public around the Louisville, Kentucky area could participate in. My contribution to the event was helping with identification of minerals and fossils being found in the collecting piles. I have been participating in events like this at the state park for the last 3 years.

This year was nice as a mix of adults and students visited the piles next to the main parking lot. Some visitors were from geology clubs in Illinois and Fort Wayne, Indiana. It was a nice weather and the visitors seemed enthused about the collecting and learning about minerals and fossils.
Inside the Interpretive Center a number of tables were set up showing micro-minerals and fossils, 12 mineral/fossil specimens for a $1, books by local geology professors, and fossil identifications. Also a number of talks were given by local experts and teachers on geological subjects.

I stayed on my shift a lot longer than planned since a lot of people had questions. Most questions were about minerals but I had some fossil questions dealing with Devonian corals and Silurian brachiopods. Fossil collecting was sparse as the piles were not yielding very many fossils. See picture of the only fossils I saw collected by a fossil enthusiast from Marion, Indiana. He found two Eucalyptocrinus crinoid cups plus some nice brachiopods. All the fossils had to be extracted from a large matrix piece.

The mineral pile was getting the most activity with tons of material from southern Illinois mine tailings. Yellow and purple fluorite was the most prevalent though clear was found as well. My challenge to the visitors was to find the blue and green fluorite specimens and at least 6 people found blue transparent/semi-transparent minerals. See picture below on a blue one. A couple of kids found small green fluorite crystals. So that was fun to see! Other minerals being found were calcite, sphalerite, barite, and pyrite.

A number of college groups seemed to be visiting, I did not get any school names but here is a picture of what appears to be a school group meeting on the fossil bed.