Physical Geography: Earth History, Plate Tectonics, Landforms, and the Rock Cycle

Comprehensive vocabulary flashcards covering Earth's eras, interior structure, plate boundaries, earthquakes, volcanic activity, surface processes, Canadian landform regions, and rock types.

Precambrian Era

The geological era during which the Earth formed with early oceans and crust, and the first simple single-celled life appeared.

Paleozoic Era

The geological era during which continents joined to form Pangea, accompanied by an explosion of marine life, the first land plants, and fish.

Mesozoic Era

The geological era characterized by the breakup of Pangea, the age of dinosaurs, and the appearance of the first flowering plants.

Cenozoic Era

The geological era during which the Earth cooled, modern mountains formed, mammals took over, and humans appeared.

Inner Core

An extremely hot solid sphere made mostly of iron and nickel at the center of the Earth, located $5,000\,\text{km}$ to $6,000\,\text{km}$ below the surface.

Outer Core

The only liquid layer of the Earth, consisting of a sea of mostly iron and nickel located $3,000\,\text{km}$ to $5,000\,\text{km}$ below the surface, measuring about $2,300\,\text{km}$ thick, which generates the Earth's magnetic field.

Mantle

A thick layer of hot, semi-solid rock divided into upper and lower sections, whose slow-moving convection currents act like a conveyor belt driving tectonic plate movement.

Crust

The solid, rocky outer and thinnest layer of Earth where organisms live, broken into several plates that move or drift on top of the mantle.

Continental Crust

The thick, solid layer of rock that makes up the continents where we live and causes earthquakes.

Oceanic Crust

The thin, solid layer of rock found on the ocean floor.

Theory of Continental Drift

The theory proposing that Earth's continents were once joined together and slowly moved apart over millions of years.

Pangaea

A single giant supercontinent comprising seven continents: North America, South America, Europe, Asia, Africa, Australia/Oceania, and Antarctica.

Plate Tectonics

The theory replacing continental drift, which demonstrated that giant crust plates float and move on top of Earth's hot inner layer.

Divergent Plate Boundary

A boundary where two tectonic plates move apart from each other and grow larger, occurring rarely on land and mostly on the ocean floor at the mid-ocean ridge.

Convergent Plate Boundary

A boundary where two tectonic plates move toward each other and collide, pushing upward to form giant mountain ranges like the Andes Mountains in Peru when two land plates smash together.

Transform Plate Boundary

A boundary where two tectonic plates slide horizontally past each other sideways, grinding against one another as they travel in opposite directions.

Earthquake

The shaking of the ground caused when massive underground tectonic plates get stuck, suddenly snap apart or slip past one another, and release powerful seismic waves to the surface.

Strike-Slip Earthquake

An earthquake formed when tectonic plates slide horizontally past each other (such as along the San Andreas Fault), exemplified by the 1906 San Francisco earthquake of magnitude $7.8$.

Thrust/Subduction Earthquake

An earthquake formed when tectonic plates collide and one plate slides underneath another, exemplified by the 1960 Valdivia earthquake in Chile at magnitude $9.5$.

Intraplate Earthquake

A rare earthquake that occurs in the middle of a tectonic plate instead of at the edges, caused by old, hidden underground cracks suddenly snapping under pressure, such as the 1811–1812 New Madrid Earthquakes of magnitude $8.0$.

Richter Scale

A scale measuring earthquake size and energy where each step up means shaking is $10$ times bigger and the energy released is about $32$ times more powerful.

Pacific Ring of Fire

A geographical ring around the Pacific Ocean where the majority of Earth's volcanoes and earthquakes occur.

Mt Tambora

A stratovolcano that produced a massive 1815 eruption of magnitude $7$ that blocked the sun and caused the 'year without a summer'.

Stratovolcano

A tall, steep volcano formed by alternating layers of lava and ash building up over time.

Hotspot Volcano

A volcano formed when hot magma rises from deep inside the Earth and breaks through the crust.

Shield Volcano

A wide volcano with gentle slopes formed when pieces of rock and ash pile up around an opening.

Cinder Cone Volcano

A small, steep volcano formed when pieces of rock and ash pile up around an opening.

Tsunami

Super-fast ocean waves caused by underwater plate slippage and earthquakes that transmit energy upward and build into giant walls of water upon reaching shallow land.

Weathering

The geological process of breaking rock down physically, chemically, or biologically.

Erosion

The geological process of moving broken pieces of rock away.

Deposition

The geological process of dropping eroded rock pieces in a new spot.

Mechanical Weathering

The physical breakdown of rock without mineral changes, such as ice cracking rocks.

Chemical Weathering

The breakdown of rock resulting from minerals changing or dissolving.

Biological Weathering

The breakdown of rock caused by living organisms, such as tree roots growing into cracks.

Canadian Shield

A Canadian landform region defined by huge, hard rocks, bumpy hills, large forests, and numerous lakes.

Interior Plains

A Canadian landform region defined by wide-open, flat grassy fields extending across vast distances.

Great Lakes - St. Lawrence Lowlands

A Canadian landform region characterized by super flat land and very rich dirt.

Appalachian Region

A Canadian landform region characterized by smooth, rounded old mountains and rocky ocean beaches.

Western Cordillera

A Canadian landform region defined by tall, pointy, snow-covered mountains.

Hudson Bay Lowlands

A Canadian landform region characterized by soggy, muddy swamp land covered in moss and water.

Innuitian Mountains

A Canadian landform region characterized by permafrost and giant icy glaciers.

Arctic Lowlands

A Canadian landform region characterized by permafrost and giant icy glaciers.

Igneous Rock

A category of rock formed through the cooling of molten material; examples include Granite and Obsidian.

Sedimentary Rock

A category of rock formed by the accumulation and consolidation of mineral and organic particles; examples include Sandstone and Limestone.

Metamorphic Rock

A category of rock transformed by extreme heat and pressure; examples include Marvel (marble) and Slate.