Earch Science Lesson 3 Study Guide
What is the name of Alfred Wegener's hypothesis about moving landmasses? continental movement plate tectonics continental drift seafloor spreading
continental drift
What is thought to be the driving mechanism of plate movement? volcanoes conduction of heat in the mantle continental drifting convection currents in the mantle
Convection currents in Earth's mantle
what was one reason that Wegener's hypothesis of continental drift was rejected? He could not explain what was moving the continents. He couldn't support the idea that climates of certain landmasses had been different. He could not support that the continents were once adjacent. He could not explain where the continents had moved.
He couldn't explain what was moving the continents
What type of force is exerted on a tectonic plate near the part of convection current where the mantle is cooling? a rising force a sinking force an elastic force a cracking force
a sinking force
Places where two tectonic plates are moving away from each other are called __________. convergent boundaries divergent boundaries earthquake boundaries transform boundaries
divergent boundaries
What evidence did Wegener use to estimate the time of Pangaea's break up? magnetic isochrons coal deposits ocean-floor topography fossil data
fossil data
The thickness of ocean sediments that are close to a mid-ocean ridge is ______ the thickness of ocean sediments that far from mid-ocean ridges. more than the same as always 100 times less than
less than
When a divergent plate boundary forms on continents, a __________ forms. crater volcano mid-continent ridge rift valley
rift valley
Harry Hess' theory of __________ explained how ocean crust is generated and destroyed. continental drift continental movement seafloor spreading plate tectonics
seafloor spreading
What is the process called when one plate is forced beneath another at a convergent plate boundary? transformation subduction convergence subtraction
subduction