EXPEDITION IN ARIZONA
February 2005
A recent discussion on the Yahoo Trilobites2 message board mentioned an interesting site in Arizona where occasional trilobites have been found. In early February my wife and I were in Tucson for the Arizona Fossil and Mineral Show. I had shopped to the point of dropping and Janis loves to find things, so we grabbed the Chihuahua and headed north on 77 past Winkleman. We found the roadcut through obvious sedimentary layers and headed up the dry creek towards the old road. There were a few sprinkles but no major rain and the moisture probably made it easier to spot our quarry. The rocks were loaded with small fossils. There were tiny crinoid stems, brachiopods, bryozoans and fusulinids everywhere. I spent a lot of time crawling along the sides of the gorge wearing my head magnifier to admire the abundance of Carboniferous life that is fossilized there. We both found some good-sized free crinoid stems in the talus and Janis found a nice big pink stem in a large hunk of limestone that I had the honor of hauling back to the car. She found an even bigger piece of limestone with a horn coral that looked like a wagon wheel. After hunting for around two hours, no trilobites were seen and we didn't find any crinoid crowns, but we had a thoroughly good time and finished the day with dinner at Tucson's Café Terra Cotta. Can life get any better than this?
Sedimentary layers exposed in the roadcut near Winkleman.
This is the Naco Formation and is from the Upper Pennsylvanian Period.
Come carry this boulder back to the car for me!
