Earth's Formation
Scientists have evidence that the Earth is how old?
What is 4.6 billion years?
The percentage of geologic time that happened in the Precambrian Eon.
What is 90%?
Earth's core is mostly composed of this metal.
What is iron?
The name of the landmass that existed long ago and was composed of all of today's continents pushed together as one large supercontinent.
What is Pangea?
These frequently occur at transform boundaries.
What are earthquakes?
The Earth's ozone layer protects living things from this.
What is (UV) radiation from the sun?
What is the Carboniferous period?
The mechanical layer of the Earth that is responsible for Earth's magnetic field.
What is the outer core?
The type of plate boundary that forms above sinking convection currents in the mantle.
What is convergent?
The name of the largest mass extinction in Earth's history.
What is the PT extinction (The Great Dying)?
The planet in our solar system that is most dense.
What is Mercury?
What geologic time unit is the longest?
What is the eon (or supereon)?
Pieces of Earth's crust float upon the slowly moving molten rock of this layer.
What is the mantle?
Seafloor spreading occurs at what type of plate boundary?
What is divergent?
New crust is created at this type of boundary.
What is divergent?
Cyanobacteria produced oxygen in Earth's early atmosphere through this process.
What is photosynthesis?
What geologic time unit is the shortest?
What is the epoch?
The mechanical layer of Earth that is under the most pressure.
What is the inner core?
The process in which the more dense plate plate gets pushed beneath the less dense plate and the crust is recycled.
What is subduction?
The theory that attempts to explain how the moon formed.
What is the Giant Impact Theory?
The theory that attempts to explain how stars & solar systems form.
What is Nebular Theory.
Since this eon had a lot of living organisms and is more recent on the geologic time scale, scientists find the most fossils from this eon.
What is the Phanerozoic Eon?
Scientists use these to study the layers of the Earth.
What are Earthquake (Seismic) Waves?
Trenches are created at these type of plate boundaries.
What is convergent?
A common type of fossil that is easy to recognize, can be found all over the world, and is used to determine the age of rock layers.
What is an index fossil?