If you have been working on the Earth Caches on these trails you may have learned what Limestone is, how it's made, properties, and what uses there are for limestone. On this Earth Cache Adventure we are going to learn about a very specific type of limestone called St. Joe Limestone.
Much of my Source Material is found from the Arkansas Gelogical Survey group, and you can get much more in depth information that what I am going to cover today. Take your time to check it out!
Who the heck is St. Joe?
At least that was the question that ran through my mind. Instead, it isn't so much who, but where. This type of limestone wasn't named after a Saint but after a loaction, a "ghost" town now, known back in the day as St. Joe, which was in Searcy County AR. ( It was like most towns of the time a mining town and comes with it own legendes.) For the sake of this Earth Cache we'll just say St. Joe Limestone was named for laction of the area found limestone of this type, and is found in Northern Arkansas, Ozark Plateaus; Oklahoma, southern Missouri (Boone Family). It is important to note that St. Joe Limestone is a fine-grained, crinoidal limestone that may occasionally contain some smoothly bedded chert. The limestones (and cherts) are frequently gray, but may also be red, pink, purple, brown, or amber.
Hey Joe whattaya know?
St. Joe Limestone is very very old, in fact limestone can tell us the what kind of Rocks and Minerals were aroudn milions of years ago. Just like looking at rings of a tree we can look at the layers of limestone. In these layers it will give us some clues as to what was going on waaaaay back when Jurassic Park wasn't a movie. One of the neatest things it will tell you forever imprinted on the stone is the animal and plant life found in Fossiles! Most of these are Crinoids, brachiopods, bryozoa, conodonts, blastoids, ostracods, and rugose coral...I know that was a mouth full, but really what all that is, is sea life in the form of shells and plants and other small critters that you may never knew existed.
All in the Boone Family Unit.
The Boone Formation a discrete and definable unit of cherty limestone rock strata located in northwest Arkansas and northeast Oklahoma.The stratigraphy of the Boone Formation dates to the Mississippian age. (This means it's old, really old) The Boone Formation is rich in fossils, and occasionally preserves the remains of sharks' teeth in outcrops along Buffalo National River. (Source)
Did You Know?
The Paleozoic Era, which ran from about 542 million years ago to 251 million years ago, was a time of great change on Earth. The era began with the breakup of one supercontinent and the formation of another. Plants became widespread. And the first vertebrate animals colonized land. Many of the fossils found in this type of limestone are from that era!
So now that we learned a little bit about St. Joe Limestone, take a moment to study ground zero, as well as the placards for GZ. With the information above, and information at GZ you should be able to answer the following questions. You have 24 hours to send me an email (found in my geocaching profile) with the correct answers. Failure to do so will result in the removal of your "Found it log". Please add the GC code and title in the subject line. If you are sending answers for multiple people in your group, please add all the names in your email to ensure they don't have their log deleted :) Photos with you or in the group of the area would be greatly appreciated.
Requirements:
1 What is the color of the Limestone Wall?
2 Is this limestone a Boone Formation?
3 What is the Estimated age of this wall?
4 Estimate (in feet) how tall this wall is?
5 According to GZ information how thick can the limestone in Bella Vista get?