Sea Floor Spreading Flashcards
What is the 3rd dudes name who was Canadian and proposed the lithosphere was broken into separate sections plates?
J Tuzo Wilson
What is the theory of plate tectonics?
It explains the formation, movement, and subduction of earth’s plates.
What are the 3 types of plate boundaries?
Transforming, divergent, and convergent. (Slide, divide, collide)
What is a Rift Valley?
It occurs when a deep valley formed along a divergent boundary that develops on land
When a continental crust and an oceanic crust collide, what happens?
The denser plate (oceanic) is subducted beneath the other forming a trench
What is a fault?
A break In earth’s crust
What are the 3 evidences that supported Vaygnurs theory of continental drift?
Land features, fossils, climate change
Sea-floor spreading
Sea floor spreads along both sides of a mid ocean ridge as new crust is added. Ocean floor moves as a conveyer belt, carrying continents with them.
What are the 3 evidences that supported Hess’s theory?
Evidence from molten material,
Magnetic stripes, and drilling samples
Evidence from molten material:
Pillow shaped rocks formed if molten material erupts and hardens quickly
Evidence from magnetic stripes:
Rocks that lie in a pattern showing a record of reversals
Evidence from drilling samples:
Reveal that the farther from the ridge the rocks were taken, the older they were
Eventually the ocean floor sinks into deep, underwater canyons called:
Deep ocean trenches where subduction takes place which allows part of the ocean floor to sink back into the mantle
