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Older Than Dirt!
Arf and Devonian Dirt
Just how old is dirt? Well, right away, we've got an upper limit, because the entire Solar System is only about 4.5 billion years old.
How does that work? Well, let's go through a brief version the history of dirt on Earth. Parts of the interior of the Earth is molten, and that heat comes up to somewhere and right now the sea floor is spreading in the middle of the Atlantic Ocean. This causes the plates to spread away from the ridge. As these plates tend to move around, two of them will, at some point, collide together. And what happens when we get a collision of plates? We form mountain ranges!
The Himalayas are not not only the tallest mountain range in the world, but also one of the youngest mountain ranges in the world. Compare this to the Appalachian mountain range, which is less than one-quarter of the height of the Himalayas, but which is the oldest mountain range in the world, with parts dating back as far as 480 million years!
Well, even 480 million years ago, the world was teeming with plants, animals, bacteria, rain, winds, and lots of other things that erode rock and produce dirt. But, this dirt, especially sand and topsoil, is subject to the most relentless force of all on Earth: gravity. Over time, this dirt finds its way --one way or another -- to the lowest elevation possible, which is to say, the bottom of the ocean.
So, although rocks may be over 4 billion years old, dirt isn't. In fact, after the end of the last ice age (around 12,000 years ago), glaciers moved much of the topsoil around North America, leaving many regions scarred and soil-less. And yet, plants, wind, rain, ice, animals, and other factors immediately began creating soil again. While there is most definitely "old" dirt that is many tens, even hundreds of thousands of years old, most of the dirt that's out there is just a few thousand years old.
All The Other Dirt
Optional: To share your experience please take a photo of yourself or your GPSr with the Dirt Display at the given coordinate in the background (see my photos above).
And to demonstrate the educational value of this EC, please email ARF! the answers to the following questions:
1. How old is the Devonian dirt?
2. How old is the Waldron Shale?
3. How old is 'All The Other' Dirt?
4. At the Additional Waypoint listed below is the high water mark for a 20th century flood. Check it out. What year was it?
Please email your answers to :
Please Do not wait on a reply from me. FOUND IT logs which do not meet requirements will be quietly removed.
Nyy nafjref ner ng gur fvgr.
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Coordinates are in the WGS84 datum