Images of an actual landslide illustrate the phenomenon. Sedimentary Rocks: The Key to Past Environments This program returns to the Grand Canyon: its exposed layers of sedimentary rock allow scientists to peer into the geologic past. Metamorphic Rocks The weight of a mountain creates enough pressure to recrystallize rock, thus creating metamorphic rocks.
The movement of sediment and its deposition are covered, and the processes of lithification, compaction, and cementation that produce sedimentary rocks are explained. This program outlines the recrystallization process and the types of rock it can create from claystone and slate to schist and garnet-bearing gneiss.
Images of landscapes illustrate how wind creates features such as dunes, playas, blow-outs, and even oases. Glaciers Many of the world's most beautiful landscapes were made by glaciers.
This program shows how, explaining glacial formation, structure, movement, and methods of gouging and accumulating earth.
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.
The evolution of rivers is covered, along with efforts to prevent harmful consequences to humans. Groundwater Approximately three-quarters of Earth's surface is covered by water. Topics of this program include aquifers, rock porosity and permeability, artesian wells, the water table, cave formation, sinkholes, and how groundwater may become contaminated. Wind, Dust and Deserts Land in arid climates is shaped in particular ways.
This program shows how deserts are defined by infrequent precipitation and how desertification relates to proximity to the equator, proximity to mountains, and ultimately plate tectonics.
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. Geologic Time To illustrate the immensity of geologic time, the entire span of Earth's existence is compressed down to a year.
The program also covers shoreline characteristics, currents, sea barriers, tides, and how the greenhouse effect could impact sea level and coastal lands. Living With Earth, Part I Scenes of San Francisco before the Loma Prieta earthquake introduce this program addressing how humans are learning to cope with earthquakes. Living With Earth, Part II Since the nineteenth century, humans have turned to the Earth for energy sources to fuel their industry.