Exam 4: Plate Tectonics

The ___ includes rocks of the crust and uppermost mantle.

Evidence in support of continental drift includes ____.

Marine geologists can predict the age of igneous rocks of the sea floor by measuring _____.

The basic idea of ______ is that the Earth's surface is divided into a few large plates that move slowly relative to one another.

The inner wall of a trench consists of a(n)_____ of thrust-faulted and folded marine sediment and pieces of oceanic crust.

Plate motion can be measured directly using ____.

Harry Hess proposed that the _______.

Measured rates of sea-floor spreading range from ______ cm/year.

Sea-floor spreading implies that sea-floor rocks should be ______________.

Magma heated by ocean-continent convergence may form a(n)_____ such as the Aleutian Islands.

The San Andreas Fault is a transform fault.

In this hypothesis the two sides of the mid-oceanic ridge are moving in opposite directions like slow conveyor belts.

The downward plunge of cold lithosphere accounts for the existence of oceanic trenches as well as their low heat flow.

The apparent movement of the magnetic poles through geologic time is called _____.

Magma that is created by ocean-continent convergence forms either island arcs or belts of igneous activity on the edges of continents.

The Rift Valley in East Africa is an example of a _____.

The most common type of transform faults offset oceanic ____.

Wegener's theory of continental drift proposed that the continents plowed through oceanic crust.

Young mountain belts,with their associated igneous intrusions,metamorphism,and fold-thrust belts,form at convergent boundaries.

Lithosphere is remarkably constant in thickness across ocean basins.