Earth's Spheres
Contains all living things.
Biosphere
The largest expansion of time is an _______
Eon
This is all major events of the Earth in chronological order and divided into units of time.
The geological time scale
The age of something in comparison to something else
Relative Age
The age of something in years
Absolute age
Contains all water on Earth
hydrosphere
The first three eons are grouped together as one big super eon called __________
Precambrian
How old is the Earth?
4.6 billion years
This law states that the youngest layers are on the top and the oldest are on the bottom
law of superposition
You can tell how old a tree is by how many _____it has inside
rings
All the rocks and minerals that make up earth
Geosphere
The rapid diversification of life on Earth at the beginning of the Phanerozoic Eon.
Cambrian Explosion
The first eon of earth was called the _______
Hadean Eon
This law states that all layers are deposited in flat layers
law of original horizontality
This isotope is one of the most popular when using half life to determine the age of the fossils of once living organisms.
C14
The gases that surround the Earth
Atmosphere
The oldest and most stable part of a continent is called the
craton
We are currently in what eon?
The phanerozoic
This law states that the layer that cuts through other layers is younger than the rock it cuts through.
Law of Cross Cutting
What element/ isotope has the longest half live and is used to determine the age of relatively older rocks.
Uranium-238
What two spheres are interacting when a river erodes the river banks.
hydrosphere & geosphere
The first organisms were ________ meaning they had no nuclei, much like bacteria
unicellular
What popular period is in the Mesozoic era?
Jurassic
This law states that all layers extend horizontally in all directions unless acted upon by geological forces.
The amount of time it takes for half of the parent atoms to decay into the daughter atoms
half-life