Lecture 1 Grand Canyon

Front 1

What is the Grand Staircase?

Back 1

Immense sequence of sedimentary rock layers stretching from Bryce Canyon NP through Zion NP and into Grand Canyon NP.

Front 2

What is the order of the canyons in the Grand Staircase from oldest to youngest?

Back 2

Grand Canyon NP, Zion Canyon NP, and Bryce Canyon NP.

Front 3

What are the names of the formations that comprises the Grand Canyon (oldest to youngest)?

Back 3

Vishnu Schist, Zoroaster Granite, Unkar Group, Tapeats Sandstone, Bright Angel Shale, Muav Limestone, Redwall Sandstone, Supai Group, Hermit Shale, Coconino Sandstone, Toroweap Formation, and Kaiban Formation.

Front 4

What are the names of the formations that comprises the Grand Canyon (youngest to oldest)?

Back 4

Kaibab Formation, Toroweap Formation, Coconino Sandstone, Hermit Shale, Supai Group, Redwall Sandstone, Mauv Limestone, Bright Angel Shale, Tapeats Sandstone, Unkar Group, Zoroaster Granite, Vishnu Schist.

Hint 4

Know The Canyon's History, Study Rocks Made By Time, Unless Zorro Vanishes

Front 5

How did the Grand Canyon form?

Back 5

Colorado River eroded rocks along fault zone as Colorado Plateau uplifted.

Front 6

When did the Grand Canyon form?

Back 6

Speculated to be 5-6 million years ago according to recent reports.

Front 7

How old is the Vishnu Schist?

Back 7

Precambarian in age; 2 billion years old.

Front 8

What is the age of Zoroaster Granite?

Back 8

Precambarian; 1.4 billion years old

Front 9

What is the depositional environment and indicators for Vishnu Schist?

Back 9

Shallow marine basin indicated by sand, mud, silt, and volcanic ash.

Front 10

What is the depositional environment and indicators for Zoroaster Granite?

Back 10

Shallow marine basin indicated by Pluton intrusion in Vishnu Schist.

Front 11

What is the depositional environment and indicators for the Unkar Group?

Back 11

Offshore marine environment indicated by sedimentary beds.

Front 12

What is the depositional environment and indicators for Tapeats Sandstone?

Back 12

Submarine environment indicated by deposition of pebbles, cobbles, and boulders; conglomerates.

Front 13

What is the depositional environment and indicators for Bright Angel Shale?

Back 13

Offshore marine environment indicated by muds with brachiopods and trilobites.

Front 14

What is the depositional environment and indicators for Muav Limestone?

Back 14

Offshore marine environment indicated by calcium carbonate precipitates.

Front 15

What is the depositional environment and indicators for Redwall limestone?

Back 15

Shallow tropical sea indicated by fossilized crinoids, brachiopods, bryozoans, and nautiloids.

Front 16

What is the depositional environment and indicators for Supai Group?

Back 16

Swampy environment indicated by sand dunes, fossil plants, footprints of amphibians.

Front 17

What is the depositional environment and indicators for Hermit Shale?

Back 17

Fluvial, lagoonal environment indicated by floodplains, ripple marks, mud cracks, footprints, plant fossils.

Front 18

What is the depositional environment and indicators for Coconino Sandstone?

Back 18

Desert environment indicated by sand dunes and sandstone.

Front 19

What is the depositional environment and indicators for Toroweap Formation?

Back 19

Marine environment indicated by fossilized brachiopods, mollusks, and corals.

Front 20

What is the depositional environment and indicators for Kaibab Formation?

Back 20

Shallow marine environment indicated by fossilized crinoids and brachiopods.

Front 21

What are the distinguishing characteristics of Vishnu Schist?

Back 21

Dark-colored rocks; 3000' below the rim

Front 22

What are the distinguishing characteristics of Zoroaster Granite?

Back 22

Light-colored, irregular bands

Front 23

What are the distinguishing characteristics of the Unkar Group?

Back 23

Presence of the Great Unconformity

Front 24

What are the distinguishing characteristics of Tapeats Sandstone?

Back 24

Cliff-former; 400' thick

Front 25

What are the distinguishing characteristics of Bright Angel Shale?

Back 25

Slope-former; 400' thick

Front 26

What are the distinguishing characteristics of Muav Limestone?

Back 26

Cliff-former; 400' thick

Front 27

What are the distinguishing characteristics of Redwall Limestone?

Back 27

Bluish-gray color; Shades of red from oxidation of iron and manganese (from Supai and Hermit); 500' thick

Front 28

What are the distinguishing characteristics of Supai Group?

Back 28

Ledge and cliff-former; 600-700' thick

Front 29

What are the distinguishing characteristics of Hermit Shale?

Back 29

Red color from shale; Slope-former; 300-800' thick

Front 30

What are the distinguishing characteristics of Coconino Sandstone?

Back 30

Tan to white color; Cliff-former; 400' thick

Front 31

What are the distinguishing characteristics of Toroweap Formation?

Back 31

Gray color from sandstone; Ledge and cliff-former; 200' thick

Front 32

What are the distinguishing characteristics of Kaibab Formation?

Back 32

Gray color with chert nodules; Cliff-former; 300' thick

Front 33

Why does the Grand Canyon has a terraced appearance when looked upon from above?

Back 33

Alterations of cliffs and slopes from the rock formations gave the terraced appearance.

Front 34

What caused the sides of the canyon to look jagged and terraced?

Back 34

Periods of stream downcutting and erosion coupled with uplifting and tilting of plateaus, and marine transgression and regression.

Front 35

What are some formations straight while other are sloping?

Back 35

Some are made of more resistant rock material (hence the cliffs) compared to the othets, which are less resistant (giving slopes).

Front 36

What is the concern of spring water in the Grand Canyon?

Back 36

Contamination of spring water as a result of uranium mining.