Science Discovery Series Episode1 : From Sandstone to Canyons

Science Discovery Series

Olympus High School

Jeff Taylor

Science Instructor

Who is Jeff Taylor? Wadi Gazelle, Sinai, Egypt

All Pictures In This Presentation Taken By Jeff Taylor

Mr. Taylor• Scientist• Explorer• Hiker

My goal is to know something about everything

I always want to know WHY?

Always looking for unique and interesting places to help explain scientific concepts to my students.

Jeff TaylorOlympus High School

• Courses:– All Science at Olympus HS– Health and Physical Education too

• Contact [email protected]

602-476-2141

Family: Wife Linda and 21-month daughter Hilina

Detailing our travels and hikes on our blog: www.taylorlenz.blogspot.com

Living out of our 22 ft trailer and spending the next 6 months in Desert Southwest.

Episode 1Sandstone: From Sand Dunes to Canyons

The Story of Lithification

Paria Canyon, AZ

Sandstone• Sandstone are layers of sand-sized particles

that are cemented together.

• Sandstone can form from sand dunes, in rivers, lake shores, or former ocean beaches.

Grand Staircase-Escalante NM, UT

Sand Dunes• Sand Dunes form where sand particles are blown in the wind

and then pile up in a place where the wind slows down.

• In this case, the Rocky Mountains block the winds.

Great Sand Dunes NP, CO

Here, winds slow when they hit those mountains, dropping off the sand

Kelso Dunes, Mojave N Pres, CA

That’s me 500 feet above the desert floor

Climbing the Highest Dunes in North America

Great Sand Dunes NP, COOver 700 feet tall of pure sand!

The view from the top!This was Utah 75 Million Years Ago

Great Sand Dunes NP, COSand dunes up to 2000 feet deep!

Lithification• Lithification means turning sand to stone.

• As rain trickles through the sand, it cements the pieces together to form stone

• Think of an example of lithification you might have created or seen!

Great Sand Dunes NP, CO

Cements are Dissolved Minerals• Minerals dissolved in water accumulate where water evaporates. • As the crystals form, they bind sand grains together like cement.• The particular minerals involved decides the cement strength.

Fossilized Sand Dunes

• Can be determined by their cross-bedding.• Cross-bedding are alternating layers that

are tilted against each other.

Navajo Sandstone, Big Water, UT

• The angled beds are the result of sand slide down the sides of the dune

• The angles change when wind direction changes and buries old dunes with new sand

Kelso Dunes, Mojave N Pres, CA

Cross-Bedding

Vegetation can also stabilize dunes

Beverly Dunes, Vantage, WA

Roots hold water and stabilize the dunes. Then sand blows over and buries the dune, preserving it

Navajo Sandstone

These fossilized dunes formed in an ancient Sahara-like Desert some 75 million years ago

The Dive, Grand Staircase-Escalante, UT

Today

How Was The World Different?

90 Million Years Ago

Area of Navajo Sandstone

75 Million Years Ago

Area of Navajo Sandstone

65 Million Years Ago

Area of Navajo Sandstone

On The Search For Dinosaur Tracks

Dinosaur Tracks

Grand-Staircase-Escalante NM, UT

Click Check Mark If You See It

Dinosaurs stepped in wet sand and then sand blew over and filled the impression

Theropod

More Dinosaur Tracks

Dinosaur National Monument

Dinosaur Bones

Dinosaur NM, CO

Bones Left in Place By National Park Service

Fossilized Palm Trees

Grand Staircase-Escalante NM, UT

Here Is How It Could Happen

Buried Palms in Sudan, Image courtesy of the UN Environmental Programme

Petrified Wood

• Fallen trees that were buried by sand ended up being preserved as these petrified tree trunks.

Escalante Petrified Forest State Park, UT

Water Deposited Sandstones

• Sandstone layers that are completely horizontal are usually formed at the bottom of lakes or the ocean.

Vermillion Cliffs Wilderness, UT

Water Deposition

• When sediment flowing down a river meet a lake, they drop out and settle to the bottom to form a flat layer.

Banff NP, Alberta

Lake Sediments

• Here, changing lake levels leave horizontal beds of sediments.

When buried, they will compact into stone.

Lake Powell, UT

Half Moon Bay, CA

Ocean Beaches

River Deposited SandstonesWahweap Creek, Glen Canyon NRA, UT

Ripple Marks

• Ripple marks are a sign on an ancient stream or lake shore

Vermillion Cliffs Wilderness, UT

Red Sandstones

• Stained by iron oxide (rust) minerals

Grand Staircase-Escalante NM, UT

Blue Sandstones Stained by CopperBlue Basin, John Day NM, OR

Erosion

• Rivers, rain, ice, and wind erode the sandstone and free the sand to form dunes once again.

Canyonlands NP, UT

Zion Canyon

2000 feet deep sand dunes cut by the river

Dinosaur NM, CO

Green River cutting into sand stone

Does anyone want to guess the rate of erosion?

Soft Sandstones

• Some sandstones are so weakly cemented, that they “melt” when it rains and fall apart in your hands.

Grand Staircase-Escalante NM, UT

Hoodoos

• When more resistant rock protects weaker rock below, columns can form.

• When the cap falls off, the towers “melt” away.

Wahweap Hoodoos, Grand Staircase-Escalante NM, UT

Slot Canyons

• Flash floods carve deep narrow canyons into sandstone.• Some storms will flood this canyon with water 80 feet high!

Buckskin Gulch, Grand Staircase-Escalante NM, UT

Slot Canyon

Spooky Gulch, Grand-Staircase Escalante NM, UT

Arches

Wind erosion is primarily responsible for natural arches.

Cobra Arch, Vermillion Cliffs Wilderness, UT