Relative Dating
This principle says that in undisturbed rock layers, the oldest layers are at the bottom
What is the Law of Superposition?
The time if takes for half of a radioactive isotope to decay
What is half-life?
List the four systems of Earth
Atmosphere
Hydrosphere
Geosphere
Biosphere
The carboniferous period saw the first appearance of this group of animals that lay amniotic eggs
Reptiles
Which appeared first, sharks or trees?
Sharks
This principle states that sediments are originally deposited in flat layers
What is the Principle of Original Horizontality?
The isotope used to date organic materials.
Carbon-14
Early photosynthetic life added this gas to the atmosphere
What is oxygen?
These early marine arthropods developed hard shells in the Cambrian
Trilobites
Which came firsts: land plants or tetrapods?
Land Plants
If two fossils are found in the same rock layer, this can be inferred about their relative age
A fossil with 25% of its parent isotope remaining has gone through _____ half-lives
Two
Cyanobacteria altering the atmosphere is an example of ...
What is coevolution?
These animals, the first vertebrates to walk on land, evolved during the Devonian
Tetrapods
Which came first: trilobites or reptiles?
Trilobites
This principle tells us that a fault or intrusion is younger than the rocks that it cuts through
What is the principle of cross-cutting relationships?
In Beta Decay, the atom releases 2 protons and 2 neutrons. The mass number goes _________ by ______.
Down by 4
What happened that allowed oceans to form?
The earth cooled
This occurs when a large number of species disappear in a relatively short period of time
Mass extinction
Which came first, amphibians or reptiles?
Amphibians
This represents a gap in the geologic record where erosion may have occurred
Unconformity
In Alpha Decay, the atom releases an electron . The atomic number goes ________ by ______ and the mass number ______________.
Up by 1
Stays the same/doesn't change
Which of Earth's systems does all life originate in?
Hydrosphere (oceans)
This Paleozoic period saw giant swamp forests that formed most of today's coal deposits
Carboniferous
Which came first, forests or coal deposits?
Forests