This program traces the development of astronomical theory with discussions of the discoveries of Copernicus, Galileo, Kepler, and Newton.
The program also surveys the various types of eruptions, craters, cones and vents, lava domes, magma, and volcanic rock. Experts provide a graphic illustration of this process and explain the types and textures of rocks such as granite, obsidian, and quartz.
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.
A relationship between this timeline and that of life on Earth is established, with fossils and radiocarbon dating playing a major role in the discovery. Evolution Through Time The fossil record reveals much about the diversity and development of species.
This program examines the traces left by early plants, animals, and single-celled organisms and follows the progression of life forms over time.
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.