Earth’s Structure & Plate Tectonics
This layer of the Earth is solid, brittle, and divided into tectonic plates.
Lithosphere
A sudden shaking of the ground caused by movement along a fault.
Earthquake
The trapping of heat by gases in Earth’s atmosphere is known as this effect.
Greenhouse effect
The process of clearing forests for agriculture or urban development.
Deforestation
Fossil fuels like coal, oil, and gas are classified as this type of resource.
Non-renewable
The boundary where two plates move apart, creating new crust, is called this.
Divergent boundary
This natural hazard occurs when hot ash, gas, and rock flow rapidly down a volcano’s slope.
Pyroclastic flow
This gas, produced by burning fossil fuels, is the largest contributor to global warming.
Carbon dioxide (CO₂)
The overuse of groundwater that causes sinking of land surfaces.
Subsidence
The process where sediments are compacted and cemented into rock.
Lithification
The driving force behind plate tectonics is thought to be convection currents in this layer.
Asthenosphere / Upper mantle
A tropical storm with winds exceeding 119 km/h is called this.
Cyclone / Hurricane / Typhoon
The layer of the atmosphere where weather occurs.
Troposphere
This renewable energy source uses moving water to generate electricity.
Hydropower
The time it takes for half of a radioactive isotope to decay.
Half-life
This boundary type creates deep ocean trenches and volcanic arcs when one plate sinks beneath another.
Convergent boundary / Subduction zone
A giant ocean wave caused by an undersea earthquake or landslide.
Tsunami
These natural records, extracted from glaciers, provide evidence of past atmospheric CO₂ levels.
Ice cores
The term for species introduced to ecosystems where they outcompete native organisms.
Invasive species
Rocks formed from cooling and solidification of magma or lava.
Igneous rocks
The theory that explains the movement of continents over geological time.
Plate tectonics
This scale measures earthquake magnitude based on seismic energy released.
Moment Magnitude Scale (formerly Richter)
The large-scale warming of ocean waters in the Pacific that disrupts global weather patterns.
El Niño
The layer of Earth’s atmosphere that absorbs most harmful UV radiation.
Ozone layer
These boundaries between rock layers represent gaps in the geological record.
Unconformities
The San Andreas Fault in California is an example of this type of plate boundary.
Transform boundary
The ring-shaped region around the Pacific Ocean known for frequent earthquakes and volcanoes.
Ring of Fire
This international agreement, adopted in 2015, aims to limit global warming to below 2°C.
Paris Agreement
Excessive nutrient runoff into rivers and lakes can lead to this oxygen-depleting process.
Eutrophication
The largest mass extinction in Earth’s history, about 252 million years ago.
Permian-Triassic extinction
When two continental plates collide, they form these large-scale features.
Fold mountains (e.g., Himalayas)
This process can trigger landslides by weakening slopes through water saturation.
Heavy rainfall / Overland flow
Methane is a potent greenhouse gas. Its main natural source is this.
Wetlands/Swamps
The 1987 agreement to phase out ozone-depleting substances like CFCs.
Montreal Protocol
The boundary between the Cretaceous and Paleogene periods is marked by this element from an asteroid impact.
Iridium
The point on the Earth’s surface directly above an earthquake’s focus is called this.
Epicenter
Volcanic eruptions can cool global temperatures due to the release of this substance into the stratosphere.
Sulfur dioxide
The fraction of incoming sunlight reflected by a surface, influencing climate, is called this.
Albedo
The measure of how much biologically productive land and water an individual or population requires.
Ecological footprint
The geologic time scale is divided into these four main eons.
Hadean, Archean, Proterozoic, Phanerozoic
Magnetic evidence from the ocean floor helped confirm plate tectonics because of these symmetrical patterns.
Magnetic striping / Paleomagnetism
The name of the most explosive type of volcanic eruption, producing high ash columns.
Plinian eruption
The tipping point where melting ice reduces reflectivity and accelerates warming is called this.
Ice-albedo feedback
Sustainable farming technique that rotates crops to improve soil fertility.
Crop rotation
The process where minerals replace organic material in forming fossils.
Permineralization
The supercontinent that existed around 250 million years ago before breaking apart.
Pangaea
In 1883, this Indonesian volcano’s eruption caused global climate impacts and massive tsunamis.
Krakatoa
The sudden global cooling event that followed the Chicxulub asteroid impact 66 million years ago.
Impact/Global winter
The concept of using resources without compromising future generations’ ability to meet their needs.
Sustainable development
The current geological epoch, defined by significant human impact on Earth’s systems.
Anthropocene