GTS
The __ __ __is a system we use to measure and describe the history of Earth.
The GEOLOGIC TIME SCALE
In the very beginning, Earth was ________ (hot molten rock or frozen icy rock?)
hot, molten rock
The first life forms on Earth were _____.
anaerobic bacteria (did not need oxygen)
What do we call the floating pieces of earths crust?
Tectonic plates
We have only looked at the first era of the Phanerozic Eon. What is the name of this era?
Paleozoic
Earth is approximately __ billion years old.
4.6 billion years old
Periods are broken down into?
Epochs
What was the name of the planet that collided with Earth to create the moon?
Thea
Mats of what developed during the Archean eon?
Cyanobacteria, Blue-green algae
The shifting of the tectonic plates broke Vaalbara apart and created what new supercontinent?
Rodina
The Paleozoic era was broken into how many periods?
6
We divide Earth’s “life” into large time units called __ (the largest Unit)
Eons
An era is further subdivided into ___.
What is periods
The first continents formed by what ?
Underwater volcanic activity
The Archean eon lasted how log (from when to when?)
4-2.5 billion years ago
The new life forms arriving on Earth began to increase the levels of Oxygen in the atmosphere. This triggered what event?
Snowball Earth. The first Ice age.
What is a mass extinction?
When a majority of life dies out in a short period of time.
What was the first Eon?
Hadean
Which eons are not divided into eras?
What is the Hadean and Archean
Water arrived on Earth via what?
Asteroids and meteor showers
What was the name of the fist Supercontinent?
Vaalbara
The first life forms were ?
Anaerobic (did not need oxygen)
What was the name of the Asteroid/comet shower near the end of the Hadean Eon?
The late Heavy Bombardment
What kept our planet from freezing over during the Archean Eon?
Green house gases in our atmosphere.