This map and summary describe the Antarctic Circumpolar Current (ACC), which is the most important current in the Southern Ocean and the only current that flows completely around the globe. The ACC, as it encircles the Antarctic continent, flows eastward through the southern portions of the Atlantic, Indian, and Pacific Oceans. Links are provided to summary text detailing velocity and hydrographic ... Full description.

This module offers an introduction to the concepts explored by Alfred Wegener, Harry Hess, and others. It is the first in a series on plate tectonics. Full description.

The distribution of earthquakes and volcanoes around the world confirmed the theory of plate tectonics first proposed by Wegener. These phenomena also help categorize plate boundaries into three different types: convergent, divergent, and transform. Full description.

This site contains 25 questions on the topic of oceanic and continental crust, which covers the physical properties and features of the two crust types. This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate verification. Full description.

This site contains 25 questions on the topic of plate tectonics, which covers the development of the theory, crustal movements, geologic features associated with tectonics, and plate boundaries (convergent, divergent, transform). This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate verification. Full description.

This Classroom Connectors lesson plan covers physical features of oceans such as currents, sea-floor spreading, ocean basins, the ocean's landscape, and the origin of the oceans. The site provides goals, objectives, an outline, time required, materials, activities, and closure ideas for the lesson. The Classroom Connectors address content with an activity approach while incorporating themes necessary ... Full description.

Appalachian Mountain landforms clearly demonstrate the relation of plate tectonics and structure to geomorphology. The folded rocks record the convergence of two continental plates in Pennsylvanian/Permian time. This page uses text, maps, and remotely sensed imagery to explain the relationship between plate tectonics, geologic structures, and the resulting landforms. It is part of an out-of-print ... Full description.

This article profiles Harry Hess, who is known as one of the truly remarkable Earth scientists of the 20th century. It describes the historical background of continental drift, ideas upon which his theories were built. The site goes on to discuss the work of Hess as a World War Two naval commander, during which he developed a system for estimating the daily position of German submarines and discovered ... Full description.

This is a brief review of the role of polar reversals in the development of the Theory of Plate Tectonics from the old continental drift concept of Alfred Wegener. It describes the physical difference between the continents and the ocean floor and also the surprising order of the magnetic bands on the ocean floor and how this led to the idea of sea-floor spreading as postulated by Fred Vines and Drummond ... Full description.

In this activity students use maps of the positions of the continents over the past 180 million years, and, with some basic concepts about climate zones, hypothesize what climate changes may have occurred due to plate movements. They will discover that even though climate zones are oriented roughly parallel to lines of latitude about the Earth, according to the theory of plate tectonics, the continents ... Full description.