Earth scientists throw around million-year ages like so many two-dollar poker chips. Humans first walked upright 6 million years ago; the dinosaurs became extinct 65 million years ago; and 4,500 million years ago the earth formed from a swirling cloud of dust and gas.
For most of us, these “deep time” numbers so far exceed our human-lives yardsticks, that they’re nearly inconceivable. But nowhere is deep time more tangible, or more scenic, than Arches National Park in Eastern Utah.
With over 2,000 arches, massive monoliths, towering spires, and sheer-sided walls, this red-rock wonderland is an unequaled landscape. In much of the US, particularly east of the Mississippi River, vegetation has done a good job of covering the evidence of our geologic past, but not so in Arches. The display of brilliant colors and natural sculptures is a photographer’s dream come true.
Most of the distinctive salmon-colored sandstone features associated with Arches are formed from the Entrada Formation. Its geologic history is complex, but it begins 250 million years ago with a mountain range to the east, which was slowly whittled down by water and wind, producing one of the largest and thickest sand dune fields in earth’s history.
Then comes the deep-time dance. The dance begins with the burial of the dunes for millions of years while the sandy sediments are compressed and solidified into sandstone. The next step is a slight uplift so the relentless sculptors, water and wind, go back to work slowly crafting the attractive shapes that we see today; it’s artful erosion at its natural best.
As you wander the park it’s nearly impossible to walk among the arches, natural bridges, and ancient sand dunes frozen in time without wondering how very, very long it must have taken to carve these massive expanses of stone?
Recently, near my home in Lexington, Kentucky, I walked the sea floor of a 450 million year-old ocean. When the delicate fossil clams at my feet were alive this area was hundreds of miles south of the equator!
Now don’t get me wrong; coming to grips with the idea of deep time is difficult, even for geologists. But with a bit of understanding about the concept we can all have more appreciation for the natural magic and beauty that surrounds us – especially in places like Arches National Park. Don’t miss it.
James & Terri
P.S. Up until the late 1700s most people believed what they read in the Book of Genesis: the earth was 6,000 years-old. But Scottish geologist James Hutton upset that Biblical apple cart in 1788, and for those that want to know more about deep time and its history this is a good start. What is deep time?