History of Earth
Map-Making Basics
Maps are two-dimensional ways of representing information about the natural and built world from a "top-down" perspective. You are probably familiar with road maps that show where roads go and which roads intersect with others and where. You also may have seen weather maps, which show weather patterns across a specific geographic area, or political maps, which show where borders are for countries and areas within those countries.
Model of a Normal Fault
A normal fault occurs when rocks break and move because they are being pulled apart. As the area is stretched, the rocks move along the fault. Each movement causes an earthquake. This model demonstrates how a block of rock is extended by a normal fault.
Modeling Earthquake Waves
An earthquake occurs when massive rock layers slide past each other. This motion makes enormous vibrations, which travel from the site of the earthquake in waves. In this activity, you will model how earthquakes move in three dimensions.
Parks Past, Present, and Future
Over Earth’s 4.5 billion-year history, tectonic upheavals and colliding plates formed mountain ranges and carved out basins. Forces of erosion and weathering have been at work to break down these landforms. Records of these processes are imprinted on the land and define distinctive landscapes around the United States and in its national parks.
Rock Abrasion
Rocks break down into smaller pieces through weathering. Rocks and sediment grinding against each other wear away surfaces. This type of weathering is called abrasion, and it happens as wind and water rush over rocks. The rocks become smoother as rough and jagged edges break off. In this activity, you will model how abrasion works.
Shoebox Geologist
Earth processes such as volcanic eruptions, floods, landslides, and glaciers leave behind evidence of their passing in the form of layers known as deposits. By studying deposits of recent geologic events, geologists are able to better understand older deposits and identify the processes that caused them.
Sinkholes in a Cup
In this activity, learn how sinkhole formations in rocks form and the danger they pose to communities.
Soil, the Forgotten Resource
Soil is often overlooked as a natural resource. Like fossil fuels, we depend on it for energy in the form of foods. And, like fossil fuels, it is nonrenewable. Soil is a delicate balance of inorganic minerals, organic matter, living organisms, soil water, and soil atmosphere. The natural development of soil is an exceedingly slow process. In a few hours, a heavy rain falling on exposed soil can remove inches of what took hundreds of years to form. Here is a simple exercise that will allow you to compare the rates and amounts of erosion that result from various land uses.
State Soil Investigation
Many states have a designated state bird, flower, fish, tree, rock, and so on. Many states also have a state soil — one that has significance or is important to the state.
The Soil Science Society of America has developed a collection of state soil booklets, designed and written by professional soil scientists from the region to share in-depth information on each state soil. Each soil booklet includes a brief history of
Take the Pulse of Your Classroom
The following activity can leverage SeisMac technology to help students understand how a seismometer records ground motions.
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