GEOL101 - Continental Drift and Plate Tectonics Vocabulary

A set of vocabulary flashcards defining key geological terms, historical figures, and evidence related to continental drift and early plate tectonics.

Lithosphere

The rigid, non-flowing outermost $100\text{--}150\,\text{km}$ layer of Earth composed of the crust and upper mantle that makes up tectonic plates.

Asthenosphere

The region of upper mantle located directly below the lithosphere that flows as a soft solid; it is shallow under oceanic lithosphere and deeper under continental lithosphere.

Abraham Ortelius

A Brabantian cartographer and geographer who published Typus Orbis Terrarum in 1564 and was the first to note the coastal similarity between the Americas, Europe, and Africa, proposing in 1596 that they were torn apart by earthquakes and floods.

Antonio Snider-Peligrini

A French geographer who proposed in 1858 that all continents were once connected, basing his theory on matching fossil plants found in both Europe and the U.S.

Alfred Wegener

A German astronomer and meteorologist who championed continental drift and published The Origin of Continents and Oceans in 1915, compiling geological, fossil, and climatological evidence.

Pangea

The supercontinent (meaning 'all lands' in Greek) formed in Earth's past when all present-day continents were joined together.

Sir Edwin ('Teddy') Bullard

A scientist who published the first modern computer-based reconstruction of Pangea in 1968, matching continental edges along the submerged continental shelves rather than present shorelines.

Glacial Striations

Scratches and linear grooves carved into bedrock by moving glaciers, leaving an imprint used to trace past ice movement directions across reassembled continents.

Paleozoic Glaciations Evidence

Glacial rock records from $540\text{--}245\text{ million years ago}$ preserved in South America, Africa, India, Australia, and Antarctica that fit together into a unified polar ice cap when reconstructed into Pangea.

Paleozoic Climate Belts

Continuous equatorial belts of coal swamps, coral reefs, desert sands, and salt deposits from $540\text{--}245\text{ million years ago}$ that line up across separate landmasses when Pangea is assembled.

Mesosaurus

A freshwater reptile whose identical fossil remains are found in South America and Africa, serving as evidence for continental drift because it could not swim across an ocean.

Glossopteris

A subpolar plant with heavy seeds whose fossil distribution across southern landmasses provided key evidence supporting connected continents.

Lystrosaurus

A non-swimming, land-dwelling reptile whose fossils are distributed across Africa, India, and Antarctica.

Cynognathus

A non-swimming, land-dwelling mammal-like reptile found as fossil specimens in both South America and Africa.

Gondwana

The southern supercontinental landmass comprising South America, Africa, Antarctica, Australia, and India, named after a tribe of native people in central India.

Rejection of Continental Drift

The initial dismissal of Wegener's theory by geologists due to overstated movement speeds, the physically impossible model of landmasses plowing through oceanic crust, and the lack of an explanatory driving force.

Paleomagnetism

The study of Earth's past magnetic field preserved in rock history, which provided modern quantitative evidence that confirmed continental movement and gave rise to plate tectonics.