Congratulations to TeamClockwork for being the first to find!
Limestone is an organic sedimentary rock. This means it was formed from the remains of tiny shells and micro-skeletons deposited on the ocean floor that have been compacted by pressure. Ocean dwelling creatures such as oysters, clams and mussels use calcium carbonate found in the seawater to create their shells and bones. When these organisms die, the shells and bones are broken down and settle to the ocean floor and become compacted over a million of years, creating limestone. What colour is limestone? It is formed by shells and bones and is a like colour like white, tan, or gray. The colour of the limestone depends on the other sediments in the mixture besides the mineral calcite, which is white; impurities such as sand, clay, and organic material are also present in the limestone and affect colour. To identify limestone, scratch it's soft surface with a sharp object to expose the white powder. Since limestone is made up of calcium carbonate it reacts with a diluted hydrochloric acid (vinegar).
St. Joseph Island is located 23 miles East of Sault Ste. Marie and 10 miles West of Bruce Mines. This island is primarily covered with glacial till ranging from boulders to fine, buff-coloured sand. Now you stand at an abandoned limestone quarry. It was primarily used during the construction of Highway 548 in the early 60's. The well defined layers can be seen as the picture above that I captured in this location, October 2013. I have also included two additional waypoints for you to visit.
1) CANOE POINT: limestone outcrop contains fossils of trilobites, orthocerus and brachiopods
2) GRAVEL POINT: contains excellent specimens of orthoscerus and bivalves in well weathered outcrops. It should also be noted that at this location, water erosion has made vertical cliffs of the limestone.
TO LOG THIS EARTHCACHE, PLEASE SUBMIT THE FOLLOWING TO ME BY EMAIL WITHIN 5 DAYS OF LOGGING YOUR FIND (THANKS):
A) Take a picture of yourself near the limestone at the quarry and post with your log (optional).
B) Try to separate some of the limestone layers. What does it look like between the layers?
C) Estimate the height of the outcrop at the quarry looking West.
D) Try to locate a fossil. Take a picture of it (optional) What types are prevalent in this Quarry location?
E) Enjoy the geological phenomena- afterall your Earthcaching!
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