What was the main view how the world worked geologically prior to the 1960's?
It was generally believed that mountains were produced by vertical forces.
The change from thinking the countries are stationary to understanding the the outer layer of earth moves slowly nearly all of the time occurred primarily because_______.
We began to make global observations that required recognition that the continents and ocean had not always been their current positions.
The former late Paleozoic super continent is known as_____.
Pangaea
Wegener thought that_______.
There was once on big continent that later broke into several pieces.
In Wegener's time, scientists thought that the occurrence of fossils of the same organism in two different disconnected continents was proof that________.
There had once been land bridges separating the continents
_____ was (were) never proposed as evidence supporting the existence of Pangaea.
Islands of Precambrian rocks along the Mid-Atlantic Ridge
Which of the following is not a type of plate boundary?
Hot spot
Which of the following major discoveries was not made near or after World War II?
Deep focus earthquakes that occur in some regions of the earth
Plate Tectonic boundaries were first identified by______.
Mapping earthquakes and volcanoes
A transform boundary is characterized by_____.
A deep, vertical fault along which two plates slide past one another in opposite directions
The figure below shows a _____ boundary.
Divergent
The lithosphere is the outer layer of the earth characterized by ____.
Hard rocks that break
The astheosphere is the second layer of the Earth characterized by_____.
Soft rocks that flow easily
Most deformation occurs along plate boundaries because_____.
The plates are in constant motion and as a result the boundaries are where they interact
When two plates move together, lithosphere is____.
Destroyed
Evidence that tensile stresses are actively pulling the lithosphere apart in an ocean ridge system is given by___.
The existence of a rift valley in a ridge system
All of the earth's ocean basins are____.
Less than 200 million years old
What is a typical rate for seafloor spreading?
2 cm/yr
Which of the following is in a place where continental rifting is occurring today?
Mt. Kilimanjaro in East Africa
Material that was once considered to be asthenosphere can change to lithosphere by____.
Cooling so that it will break
Oceanic island arcs are similar to continental volcanic arcs in that_____.
Oceanic islands arcs form by the same mechanism as continental arcs
Oceanic lithosphere subducts (sinks into the athenosphere) because_____.
Old oceanic lithosphere is more dense that the athenosphere
Mount St. Helens and the other Cascade volcanoes are_____.
Young, active stratvolcanoes built on a continental margin above a sinking slab of oceanic lithosphere
The Himalayas formed as a result of______.
A continent-continent convergence
The______ is an example of an active, continent-continent collision.
Northward movement of India into Eurasia
Deep ocean trenches are surficial evidence for_____.
Sinking of oceanic lithosphere into the mantle at a subduction zone
An identifying characteristic of convergent boundaries is_____.
Deep, linear trenches in the seafloor
Volcanoes form above subduction zones because______.
Water is squeezed out of the subducting slab and the water triggers melting of the overlying asthenosphere
The San Andres fault zone in California is an example of ______.
A transform plate boundary
Which ocean formed as a direct result of the breakup of Pangaea?
Atlantic
Which of the following is not evidence collected by the Glomar Challenger in support of the Plate Tectonics model?
Continental crust is typically several hundred million years old or older.
The Hawaiian Island-Empeor Seamount chain formed as a result of_______.
Hot spot activities
What is GPS (Global Positioning System) used for in the study of plate tectonics?
It measures velocity of a plate
The major driving force of Plate Tectonics is______.
Subduction of cold, dense lithosphere
Which of the following is considered the most important driving factor for Plate Tectonics?
Slab pull
Chose the option which does not fit the pattern.
oceanic ridge seafloor spreading arc volcanoes divergent
Chose the option that fits the pattern.
Hawaii island arc volcanic arc subduction