Earth Science, Geology, and Natural Resources

A comprehensive vocabulary review of Earth science, geological eras, rocks, fossils, mining methods, fossil fuels, and raw materials based on lecture notes.

Earth's core

The innermost part of the Earth. It consists mainly of iron and nickel.

Earth's mantle

The thick layer between the Earth's core and crust. It consists of very hot rock that moves slowly.

Earth's crust

The thin, outermost layer of the Earth where we live.

Geological time scale

A timeline that divides Earth's history into different periods.

Precambrian

The oldest and longest period in Earth's history. The first simple life forms appeared during this time.

Paleozoic

A geological era in which many different forms of life developed.

Mesozoic

The age of dinosaurs. It ended about 66 million years ago.

Cenozoic

The current geological era. Mammals developed and humans eventually appeared.

Pangaea

A supercontinent where almost all continents were connected. It later broke apart into the continents we know today.

Permian-Triassic extinction

The largest mass extinction in Earth's history. About 252 million years ago, most species disappeared.

Cretaceous-Paleogene extinction

A mass extinction about 66 million years ago when the non-flying dinosaurs became extinct.

Mass extinction

A period when a large number of species become extinct in a relatively short geological time.

Formation of the Solar System

The creation of our Solar System about 4.6 billion years ago from a large cloud of gas and dust.

Fossils

The preserved remains or traces of plants and animals that lived millions of years ago.

Sedimentary rocks

Rocks formed when layers of sand, clay and other sediments are pressed together and harden.

Metamorphic rocks

Rocks that change because of high pressure and temperature without completely melting.

Igneous rocks

Rocks formed when magma or lava cools and becomes solid.

Relative dating

Determining whether a rock or fossil is older or younger than another, without knowing its exact age.

Absolute dating

Determining the exact age of a rock or fossil in years, for example using radioactive materials.

Rock cycle

The continuous process in which rocks change from one type into another.

Proxy indicators

Indirect evidence that scientists use to learn about the past, for example past climate conditions.

Superposition

The principle that in undisturbed rock layers, the oldest layer is at the bottom and the youngest is at the top.

Mineral resources

Natural materials found in the Earth that humans can use, such as metals, coal and oil.

Fossil fuels

Fuels formed from the remains of plants and animals that lived millions of years ago. Examples are coal, oil and natural gas.

Coalification process

The process in which dead plant material slowly changes into coal because of heat and pressure over millions of years.

Open-pit mining

Extracting minerals by digging a large open mine at the Earth's surface.

Shaft mining

Extracting minerals from deep underground using vertical shafts and tunnels.

Formation of oil

Oil forms from the remains of tiny organisms buried under layers of sediment and transformed by heat and pressure over millions of years.

Formation of gas

Natural gas forms when buried organic material is transformed by heat and pressure over millions of years.

Formation of coal

Coal forms from dead plants in ancient swamps that are buried and compressed over millions of years.

Carbon

A chemical element found in all living organisms and fossil fuels. Its chemical symbol is C.

Reservoir rock

A porous rock where oil and natural gas collect and are stored underground.

Source rock

The rock in which oil and natural gas originally form from organic material.

Coal

A solid fossil fuel formed from ancient plant remains. It is used to produce energy.

Iron ores

Rocks containing iron that can be extracted and used to produce steel.

Crude oil

A liquid fossil fuel extracted from the Earth. It is used to produce petrol, plastics and other products.

Natural gas

A fossil fuel in gas form, used for heating and producing electricity.

Critical raw materials

Materials that are very important for the economy but may be difficult to obtain, such as lithium and cobalt.

Conflict minerals

Minerals whose extraction or trade can contribute to armed conflicts or human rights abuses.

(Energy) independence

The ability of a country to produce enough energy without depending on other countries.

Recycling

Processing used materials to turn them into new raw materials or products.

Reuse

Using a product again instead of throwing it away.

Substitution

Replacing one raw material with another material that can perform the same function.

Product efficiency

Designing and using products so they need less energy and fewer raw materials.