Hi, welcome to Grand Canyon National Park.
My name is Rachele Funk, with Grand Canyon Conservancy.
I'm a 5 foot 6 inch tall
female.
It's a beautiful sunny day and I am standing on the rim,
with the colorful rock layers and carved formations of Grand Canyon behind me.
Is this a place where
you can imagine sharks?
How about giant dragonflies with wings a
foot in length?
or wet swamps covered in ferns?
It's hard to imagine finding all of that
in the desert isn't it?
To see those things, we would have to travel back into deep geologic time,
and my friend, Ranger Tarryn, is here to help us do that.
Hi, I'm Ranger Tarryn.
As you might be able to tell by my uniform and hat, I'm a National Park Service Ranger.
What a great place to learn about
geology and ancient environments!
The Grand Canyon is one of the few places on the planet where you can look a mile
down into the Earth and see the Earth's
history told in the story of rocks.
And what a story they have to tell!
The Grand Canyon we see today took millions of years to be created.
Take a look at the
canyon with the different layers of rocks.
You can tell the layers apart by their
different colors of tan, red, green, black,
pink, and so on.
Each rock layer was created at a different time in Earth's history,
when the environment here looked
very different.
The rock layers have clues to what the environment looked like millions of years ago.
Since people weren't around when the canyon was formed,
how did geologists know what the
environment looked like?
Fossils!
Fossils are the preserved remains or traces of animals, plants, and other organisms from the past.
Not every living thing becomes a fossil: it takes just the right conditions for it to happen.
Here we see a fossil coming out of a tan-colored rock. I'm seeing lots of ridges on it.
What does that remind you of?
This fossil looks like two animals to me, inside of a dark, black-colored rock.
The rock feels pretty smooth
but the animals are sticking out a bit.
I wonder if those animals are similar to any we might find today.
This third fossil is a greenish,
grayish-colored rock.
The fossil's a lot longer.
It looks almost like roots of a tree
or maybe even a bowl of pasta.
Fossils are found in sedimentary rocks
and show us what lived at another time.
Sedimentary rocks are made over a long period of time
out of what was in the environment—mud, sand, debris, and dirt—that built up over time.
Let's take a look at one of the sedimentary layers found here at Grand Canyon,
the Coconino sandstone, and see what secrets about the past its fossils might tell us.
Can you see the tan layer of rock just below the rim of the canyon?
It really stands out, doesn't it?
It looks like a bathtub ring along the
edge of the canyon.
That's a sandstone layer. What does its
name tell you about what it was made from?
If you could rub it with your
fingers, what would it feel like?
Millions of years ago, there used to be giant sand dunes in this area.
The dunes were so extensive, they
stretched from Arizona up into Montana.
What kind of plants or animals do you think would have lived here when there were sand dunes?
Over a lot of time and changes due to the climate and geologic processes
the sand dunes were eventually
turned into solid rock like you see here.
Here's a fossil from this layer. Those small dents you see on the tan background are animal tracks.
Based on this kind of fossil evidence, geologists believed that the tracks were left behind by an animal
that may have looked like some kind of mammal-lizard mix
that had adapted to living in a dry environment.
This is what the ancient
environment may have looked like.
The environment would have included mostly large sand dunes,
with small areas where plants might grow, perhaps similar to some sand dunes you might see today.
Paleontologists—people who study fossils—think that the tracks left in the sand
are from this mammal-lizard animal going
up the side of a dune.
Many ancient environments have come and gone over time—swamps,
sand dunes, oceans, inland seas—leaving their fossil clues behind in the beautiful rock walls of Grand Canyon.
Fossils show us what used to live
in the past.
By comparing fossils with what is alive today and what we know about different environments,
we can get a feel for what
the Earth looked like millions of years ago.
Think about where you live: has the
environment changed over time?
How could you find out what it looked like many years ago?
Thanks so much for joining us today! Be
sure to check out our online geology activities
and explore the geology in
your neighborhood as well.
Check out our video on ecology coming soon, bye!
