June 2009 Archives

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

Again, the soft, porous limestone that is generally colored the same as red clay. Only this find was made in a lighter colored section of the rock that had hardened.

Trilobites are about as common in Benton county, Arkansas as speeding Buicks in Bella Vista. When you see one, you sit up and take notice.

I've been fossil hunting pretty hard for the last couple of months, and I've found one weathered cast on the exterior of a rock, and two posterior halves inside rocks I had cleaved open.

I found this specimen about two hours ago. It was an exciting moment, like having a Buick with a handicapped license plate blast around you doing 75! More pics in the article.

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

Grey fragments of mollusk shells can often be found in the crinoid-rich limestone of Benton county, Arkansas. This is a nicely intact specimen dug from the matrix. Note the parasitic borings on the enlarged version of the picture.

This elf's cap-shaped critter has a tail that reminds me of a brachiopod, but it is elongated too much to be one, IMOH. Any ideas? More pics in this article. Update: Thanks to visitor Barry for identifying both of these specimens as Platyceras species!

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

This branching crinoid stalk in matrix looks to be the same species as by bodacious huge stalk pictured elsewhere on this site.

This tube-shaped fossil has turned up from time to time in soft, porous limestone. I have found some twice this one's diameter. Any ideas? Update: This fossil has been identified by visitor Angela as a rugose coral. Thanks!

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

Again from the very soft red rock that I've referenced elsewhere, almost more like dirt clod than solid rock, here are some strange looking fossils which I presume are bryozoan in nature. This is a shot of a cast.

This is a second cast, you can see that the rock is so fragile that it's splitting. That fragile rock preserves some amazing detail, though.

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

My friends over at http://www.lakeneosho.org/ have already done most of the work for me here. This is clearly an evactinopera species. Thanks, Barry, for correcting my identification of this species to, and I quote: plates from a crinoid ... often the crinoid head falls apart before fossilization and the different plates are fossilizes separately.I have never before found one, then again they are easy to lose in the melange of small fossils that populate the limestone in which I spotted this one. I'll be keeping my eyes peeled for more, that's for sure.

Anyhow, an exact species identification would be great, if anyone knows!

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

This one is a total mystery. It was found in some hard limestone that was mostly layer upon layer of three of four species of brachiopods. There was also a lovely trilobite in the cube-shaped rock that was about ten inches square. I was able to repeatedly cleave it with the grain so that I kept uncovering layer after layer of goodies.

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

I found this specimen inside some soft limestone that is almost like sandstone in its consistency. The rock is quite porous and soaks up a lot of water.

The specimen is about 1/4" in size. It has a maze of tiny structures resembling arms. My microscope cam magnified them nicely.

Click on images to enlarge, found in Benton county, Arkansas, Boone limestone formation

There it sat, so huge that I didn't think it was a fossil.

I found some very nice limestone in a ditch just north of Bentonville. It was in many layers, a bunch of individually formed rocks ranging from palm-sized to perhaps three feet around, all an inch or three thick. I found a bunch of nice crinoid stems and a piece of a calyx. However, everything was typically crinoid-sized.

There were a few thick slabs that lined the bottom of the wash, and this puppy was sticking out like a sore thumb. However, I had looked at it two or three times without recognizing it as a crinoid stalk.

However, I finally looked closer and about jumped out of my skin when I recognized the five-sided interior as a crinoid fossil. I had to return the next day with a sledge hammer in order to liberate it from the 7" thick slab. It was sticking out of the end, having sat there for eons, waiting for me to liberate it.