Earth Revealed

Oil wells do more than just produce oil — they serve as windows to Earth's interior. This program introduces the topic of geophysics, exploring methods of studying what lies beneath Earth's surface. Geophysicists use seismic wave studies, variations in temperature, magnetic fields, gravity, and computer simulations to create models of deep structures.

The mysteries of the ocean floor lie hidden under enormous pressure and total darkness. This program looks at the research submersibles and indirect methods used to study the bottom of the sea, providing a glimpse of volcanic activity, formations such as the continental shelf and mid-ocean ridges, and life forms that thrive at extreme depths.

In the 1960s, earth scientists developed the theory of plate tectonics. This program traces the development of plate tectonics, beginning with the contributions and methods of geologist Alfred Wegener. Sea-floor spreading, continental drift, paleomagnetism, and the primordial supercontinent Pangaea are some of the topics covered.

This program examines the movement and interaction of tectonic plates, which account for a vast array of geologic formations and phenomena — from California's San Andreas Fault to the Rift Valley of eastern Africa. The program covers convergent boundaries, subduction, hotspots, and the debate over what drives plate motion.

This program erodes the myth of the mountain as a solid, permanent structure. Animations are used to illustrate the process of orogeny (mountain building) through accretion and erosion, as well as the role of plate tectonics, the rock cycle, and how different types of rock are formed in the course of mountain building.

A visit to the Grand Canyon lays the foundation for this exploration of rock layers and deformation. The program covers sedimentation, major structures, the methods used to examine them, and how petroleum may be trapped inside them. It also looks at tectonic force and the different types of stress involved in the formation of geologic structures.

Showing actual footage of earthquakes and their aftermath, this program discusses the forces that fuel these massive events. Faults, waves, and the transfer of energy from the epicenter are explained, and histories of the seismograph and Richter scale are presented. The program also describes devices being developed to study — and eventually predict — earthquakes.