Exam 2: Plate Tectonics: A Unifying Theory

How are hot spots used for determining the absolute motions of plates?

The first person to suggest that all of the continents had originally been joined together as the supercontinent Pangaea was who?

Paleomagnetic data plotted on a map suggested that the magnetic pole had moved through time; this phenomenon was called ____________________.

Which are not associated with a mid-ocean ridge?

Fossil evidence of the links among Gondwana continents was compelling because the species ____.

Briefly explain how convection transfers heat.

The forces operating at continent-continent convergent boundaries are ____.

Briefly explain why apparent polar wandering is "apparent."

That the northern continents were once joined and located along the equator was shown by what?

The west coast of South America is a convergent boundary.

The southern supercontinent consisted of which current continents?

Glacially deposited strata were important in the development of continental drift theory because ____.

The proposal that the coastline fit of South America and Africa was evidence of continental drift was criticized because it could have been due to what?

Magnetic iron-bearing minerals that crystallize out of magma ____.

Briefly explain the roles of magma and hydrothermal activity in forming ore deposits along convergent and divergent plate boundaries.

At mid-oceanic ridges,hot magma rises from the ____________________ and forms new ____________________.

The name given to the northern supercontinent was ____.

Glacial deposits gave strong evidence of the existence of Gondwana because ____.

What are four of the many things that plate tectonics theory explains?

Radiometric dating shows that the oldest ocean crust is ____________________ years old,and the oldest continental crust is ____________________ years old.