Geologic Time Line

Facts

• Geologic time is measured in millions of years.
• Millions of years is abbreviated as MYA
• There are 4 major divisions of time.
• They are Precambrian, Cenozoic, Mesozoic, and Paleozoic
• Earth is about 4.6 billion years old
• The oldest dated rock is 4.2 billion years old

More facts:

• 206-144 MYA dinosaurs dominate
• 65-50 MYA Rocky Mountains form
• 24-25 MYA modern birds appear
• 1.8 million-10,000 years ago "Great Ice Age"
• 10,000 years ago human civilization develops

Precambrian 4,600-544 MYA
Geologic Events:
First ice age occurs
First sedimentary rocks are formed
Oceans formed
Life Events:
Simple Life forms
Earth forms

Life Events:
Simple life begins

Paleozoic 544-248 MYA
Geologic Events:
Appalachian Mountains form
Warm Shallow seas cover much of North America
Two ancient continents are found near the equator
Life Events:
Age of ocean life(fish and reptiles develop)
Hard bodied animals

Mesozoic 248-65 MYA
Geologic Events:
Widespread volcanic activity
American and Europe/African continents move apart
Life Events:
Age of Dinosaurs

Cenozoic 65-0MYA
Geologic Events:
Thick glaciers in much of the world
Rocky Mountain, Alps, Andes, and Himalayas form
Glaciers cover North America
Life Events:
Age of mammals

Timeline of Utah Geology
2,000 MYA basement rocks deposited.

Utah 1,200-350 MYA

• Utah under warm seas(1,000 MYA)
• Quiet shallow marine life
• Stacking of rocks (sandstone, shale, limestone, fossil rocks)
• Rock Canyon, Provo

350-200 MYA

• Formation of Domes and basins
• Sand and mud deposited in thick layers
• Oquirrh Basin (Provo Canyon)
• Paradox Basin

200-80 MYA

• Desert environments, sand dunes deposits
• Mountain building and compression of land
• Cache Valley
• Zions Park
• Dinosaur National Park