Plate Movement Flashcards
define thermal convection
believed to be responsible for plate movemen
what do you call the upper part of the Earth’s mantle?
asthenosphere
cooler,denser material descends carried by _______________
convection current
how is an ocean ridge formed?
two convection cells meet and move upward
TRUE/FALSE:
Warm, less dense material of the lower mantle rises very slowly in the regions of oceanic ridges
TRUE
The _________________ have revealed that the flow of material in the mantle is very complex
availability of new technologies and modern research techniques
plate movement occurs because of two processes called ____________ AND _________
slab-pull and ridge push
the subducting cold and denser slab of lithosphere pulls the rest of the plate as it moves down-ward into the asthenosphere
slab-pull
a German meteorologist, proposed the continental drift hypothesis
Alfred Wegener, 1912
the theory where all landmasses were originally united in a single supercontinent
continental drift theory
a Greek word meaning “all land.
Pangea
What evidence did Wegener have that the continents were joined together in a gigantic landmass?
the matching of the shorelines of two continents, South America and Africa
similarity of rock types and structures on both sides of the Atlantic Ocean
The fossil remains of animals like the ___________
Mesosaurus
The fossil remains of the _____________ flora found in South America, Africa, India, Antarctica, and Australia
Glossopteris
where was the Glossopteris found?
South America, Africa, India, Antarctica, and Australia