Exam 19: Plate Tectonics

The portion of a fracture zone between two offset portions of ridge crest is called a ____.

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

The downward plunge of cold rock at convergent boundaries accounts for the existence of _____.

The San Andreas Fault is _________ in California.

The portion of a fracture zone between two offset portions of a ridge crest is called a transform fault.

When a ridge subsides sea level may rise.

The Himalayan Mountains are thought to have formed ____.

A _____ plate boundary is where plates are moving away from each other.

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

The ___ includes rocks of the crust and uppermost mantle.

This type of plate boundary the two plates can consist of ocean-ocean, ocean-continent, or continent-continent crust.

The head of large plumes that form "hot spots" may cause uplift and ____.

____ is the idea that continents move freely over Earth's surface, changing their positions relative to one another.

The asthenosphere is a mantle zone of low seismic wave velocity that behaves in a ductile manner.

The Vine-Matthews hypothesis provided a means to measure the rate of sea-floor spreading.

Divergent plate boundaries can occur where spreading occurs under a continent, for example ___.

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 ____.

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

Hess's original hypothesis was that sea-floor spreading is driven by deep mantle ____.