Limestone is formed from the decay of marine life. When they die, they sink to the bottom. Now, all living things must have phosphorous as it makes up DNA. When the animal dies, the phosphorus decays as well and over time, forms a hard layer of rock we know as limestone. Limestone gets its distinctive color from the calcium in the rock from other parts of decaying organic mater. Over millions of years, this limestone has lifted out of the ocean from below sea level, to this site at a rate of about two millimeters every year.
Limestone forms from phosphorus rich dead organic matter that falls to the bottom of lakes and oceans. Overtime, limestone is brought to the surface and looks like this:
The reason why the limestone used in the creation of the art sculpture is much darker in color is due to the fact that it contains more carbon than normal limestone. Carbon with some pressure and heat looks like darker rocks, more mafic in color. Examples would be coal or graphite which are both dark in color. The carbon could have came sue to the fact the sea shore was close to a swampy area at the time the limestone was being formed. A swamp takes carbon out of the air and places some of it in the ground via photosynthesis. Some of this carbon from the air gets tramped in the wet slug which will eventually harden and become this limestone.
Works Cited
http://www.kilkennylimestone.com/irish-blue-limestone/technical/
http://geology.com/rocks/limestone.shtml
http://www.sharkbay.org/geological_foundations.aspx
TO LOG A FIND ON THIS CACHE YOU MUST GIVE ME THE CORECT ANSWERS. YOU CAN CONTACT ME THROUGH MY EMAIL OR THE GEOCACHING MESSAGE CENTER. ANY INCORRECT ANSWERS WILL RESULT IN A DELETED LOG
1. "In the Tides of Time" on the first line of your email AND list all geocaching names of your party so I can match your answers to them. Note, this IS cheating as only the person who sent their answers has learned something, while the others get a "free ride". It's not fair to others. If you all want to learn something, I would prefer each cacher send me individual emails in the spirt of earthcaching.
2. Describe the (a) texture AND (b) colors of the limestone at this location. Compare the smooth cut surface to the rough cut and explain the differences noted.
3. Explain the erosion process here AND how it has effect the limestone. Is there any rusting or corrosion. If so, where do you see it AND why is it occurring. Compare the smooth cut surface to the rough cut and explain the differences noted.
4. Look very closely for any evidence of fossils. Explain what you see or don't see. Why do you think this is the case?
5. Would you expect to find fossils here if you broke open a sample of this limestone?