I've also decided to do a few posts about the local geology, because well, that's what I do. Driving past the post office today, I decided to stop because it's constructed of these fabulous limestone bricks.
All of Florida is basically made of limestone, which in turn is made up of the calcium carbonate detritus of sea creatures. Since the state is now mostly above water, we can conclude that either the water was higher or the landmass was lower in the past. Zooming into the block, we can see that it has a high percentage of corals in it. This is very informative- for the most part, coral doesn't live as far north as Daytona Beach.
But can we tell even more? In this case, we can. Looking closely, we can identify the specific genus - Montastraea. This is a common Caribbean coral that has been living around here for around 10 millions years (maybe more).
However, one more detail is really useful-- this particular Montastraea shows a columnar growth form in places! That means that we're specifically looking at Montastraea nancyi, an extinct form named by John Pandolfi that lived from 600ka to maybe 85ka. This means that the rock we're looking at is the Key Largo limestone, which is loaded with these kinds of corals. The Miami limestone also has abundant corals - but of different species. This shows how handy paleontology is - just looking at the fossils can tell you not only how old a rock is, but where it's from! Clearly, the architect decided to invest in shipping this rock a long distance instead of using anything more local. I think that was a good choice, since it's a pretty cool rock.
PS- The species name "nancyi" means, literally, more than one Nancy. It's names after two well known Nancys that are preeminent in the world of fossil coral - Nancy Knowlton of the Smithsonian Institution, and Nancy Budd of the University of Iowa - my MS adviser.
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