Paved the way for the emergence and acceptance of the plate tectonics theory.
Continental Drift hypothesis
The Continental Drift hypothesis was proposed by a German meteorologist and geophysicist named?
Alfred Wegener
He named this supercontinent (from the Greek words pan meaning “all” and gaia meaning “land”).
Pangaea
Evidence of the Continental Drift Hypothesis
Continental Jigsaw Puzzle
Fossils
Similar Rock Types and Geologic Features
Ancient Climates
After World War II, extensive ocean exploration led to the discovery of the global oceanic ridge system, which spans the globe, making it the longest mountain range (around 80,000 km long).
New oceanic crust forms in the axis of this ridge system. Because of this, rocks become progressively older and thicker with sediment away from the axis.
This phenomenon was termed seafloor spreading by Harry Hess and Robert Dietz.
Seven major plates cover 94% of the Earth’s surface area:
African plate
Antarctic plate
Eurasian plate
Indo-Australian plate
North American plate
Pacific Plate
South American plate
Plates are always in constant motion. Because of this, the plates’ margins always interact with one another. The sites where these margins interact are called?
Plate boundaries
Divergent plate boundaries are formed when two plates move apart relative to each other. These plate boundaries are also called?
Constructive margins
Divergent boundaries within a continent generate an elongated depression called?
Continental rift
These rifts form by the stretching and thinning out of the lithosphere.
Continental rift
Convergent boundaries are the sites where plates move towards each other, resulting in a collision or one plate going under the other in a subduction process. They are called?
Destructive margins
In a subduction zone, partial melting is induced in the overlying continental crust, producing volcanic activity called continental volcanic arcs. The subduction of the oceanic crust usually results in large, deep linear depressions on the ocean floor called deep-ocean trenches.
Because continental crust is too thick and buoyant to be subducted, most crustal material is deformed and pushed up instead. This results in the accumulation of sediments and rocks along the margin, forming mountain belts in a process called?
Orogeny
Transform plate boundaries are characterized by two plates sliding past each other, not destroying or producing new crustal material. They are also called? and are usually found in fracture zones.
Transform faults
An active transform fault lies between the?
Two offset oceanic ridges
Are linear breaks on the ocean floor that run perpendicular to oceanic ridges?