🌍 Earth's History
This timeline organizes Earth's history into eons, eras, and periods.
What is the Geological Time Scale?
These massive pieces of Earth's lithosphere float on the mantle.
What are tectonic plates?
Rocks formed by cooled magma or lava are called this.
What are igneous rocks?
This hazard results from sudden crust movement along faults.
What is an earthquake?
Cutting down large areas of forests is called this.
What is deforestation?
These types of rocks often contain fossils.
What are sedimentary rocks?
This process causes plates to move due to mantle convection.
What are convection currents?
The continuous process that changes rocks over time.
What is the rock cycle?
These giant waves are caused by underwater earthquakes or volcanic eruptions.
What are tsunamis?
Energy sources like wind, water, and solar are described as this.
What is renewable energy?
Fossils that help determine the relative age of rock layers are called this.
What are index fossils?
A boundary where plates collide, forming mountains or trenches.
What is a convergent boundary?
Heat and pressure transform rocks into this type.
What are metamorphic rocks?
This weather event forms spinning funnels of air.
What is a tornado?
Burning fossil fuels increases these heat-trapping gases in the atmosphere.
What are greenhouse gases?
The extinction of dinosaurs is linked to this catastrophic event.
What is a meteor impact?
This supercontinent existed over 200 million years ago.
What is Pangaea?
Sedimentary rocks form from these two processes.
What are compaction and cementation?
These intense storms form over warm ocean waters.
What are hurricanes?
These panels convert sunlight into usable energy.
What are solar panels?
Scientists use this to study patterns of life and evolution in rocks.
What is fossil evidence?
These underwater ridges are formed at divergent plate boundaries.
What is a mid-ocean ridge?
Fossil layers found in this part of Earth's crust provide clues to its history.
What is rock strata?
This scale measures the strength of earthquakes.
What is the Richter scale?
Recycling reduces the use of this type of resource.
What are nonrenewable resources?