Friday, September 20, 2013

How old is "old"?

Last weekend was my 30th birthday.  I kept joking that this was the year I turned "officially old".  Just a few short years ago I was rocking my twenties, and now here I am at the big three-oh.  How time flies.  It's fitting, then, that I put time into sharp relief for this milestone year with a different kind of collecting trip for something REALLY old.

My oldest definitively date-able find so far is a large US penny, known as a "Liberty Cap" cent.  Although the date is worn smooth, the size and style place its manufacture in either 1795 or 1796.  My oldest man-made object is a Native American stone projectile point, found by eye while metal detecting.  Known as a Guilford point, it's somewhere in the neighborhood of 4000 years old.  For perspective, that's right around when the Pyramids of Egypt were under construction.  Now that's old!  And yet, it's a drop in the bucket compared to my weekend finds.  My brother Tim and his wife Beth took me out on one of their collecting adventures to look for fossils going back 55 MILLION years.  Maybe 30 isn't so bad after all!

Using a combination of sifting, chiseling, and scanning by eye we collected several different types of fossils from the Paleocene era along the banks of the Potomac River in Maryland.  There was a narrow strip of beach at low tide (and none at all when the tide came in) butting up against a fossil rich deposit known as the Aquia Formation.  It's highly illegal to dig into the side of the cliff for reasons of erosion control and property rights, but anything that erodes out from the cliff face is fair game.  Several large recently-fallen chunks of the cliff face lay on the beach, with mollusk and gastropod fossils clearly exposed.  The sand of the beach contained many thousands of fossils which had previously eroded out into the river.

By far the most common finds for all of us were shark teeth ray teeth (referred to as "plates").  Most of the shark teeth were from various species of sand tiger sharks or the extremely funny-looking goblin shark.  The more interesting teeth included a few from either Otodus or Cretolamna, Beth's angel shark tooth, and Tim's massive 2 inch ray plate.  Beth found several fossilized bone fragments, though it's impossible to say what they may have come from.  Tim found a small piece of fossilized turtle shell.  Any my favorite find was a fossilized crocodile tooth!  Can you imagine a croc in the Potomac river nowadays?

Thanks again to Tim and Beth for taking me out fossil hunting with them. Check out the video below for some live-action shots and additional images.  Oh yea, and I've been out metal detecting since then too, but you'll have to wait for another blog post for that one.  Thanks for reading, and God Bless!

1 comment:

  1. Great post! We had a really fun time out there and were so happy to share the day with you finding some really cool stuff.

    - Tim