This program examines the traces left by early plants, animals, and single-celled organisms and follows the progression of life forms over time.
Connections are drawn between atmospheric gases, climate change, rock formation, biological functions, and mass extinctions. Minerals: The Materials of Earth Minerals have been indispensable to human civilization.
The timeline of major geologic events is superimposed onto the year for a condensed view of Earth's evolution.
The program covers convergent boundaries, subduction, hotspots, and the debate over what drives plate motion. Mountain Building 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. Earth's Structures A visit to the Grand Canyon lays the foundation for this exploration of rock layers and deformation.
Unique characteristics of Earth are also discussed. Earth's Interior 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 Sea Floor 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. The Birth of a Theory In the 1960s, earth scientists developed the theory of plate tectonics.
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. Earthquakes Showing actual footage of earthquakes and their aftermath, this program discusses the forces that fuel these massive events.
Once again, plate tectonics is shown to be involved in the process. Weathering and Soils The Cleopatra's Needle obelisk in New York City's Central Park is severely weathered after only 75 years, whereas the dry climate of Egypt has preserved similar structures in that country for millennia. Mass Wasting Anyone undertaking a building project must understand mass wasting the downslope movement of earth under the influence of gravity.