Shoebox Geologist Activity Source: Adapted with permission by National Park Service. 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. A fundamental principle of geology is the Law of Superposition, which states that younger layers will be deposited on top of older layers. [Read More]

Soil, the Forgotten Resource Activity Source: Adapted with permission by Ward’s Natural Science. 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. [Read More]

The EarthTrek Gravestone Project Activity Source: Geological Society of America. Adapted with permission. Raindrops contain more than just water. In addition to the small particles of dust around which water drops form, raindrops can contain chemicals found in the atmosphere. Often rain is slightly acidic. This “acid rain” can chemically affect (weather) materials it touches. The amount of weathering differs from place to place and changes over time. Marble, a stone commonly used to make gravestones, is mostly made up of the mineral calcite. [Read More]

Watch Out for Landslides Activity Source: Adapted with permission by the Association of American State Geologists, from AGI’s Earth System Science in Your Community. Background Landslides not only are dangerous — causing on average more than 25 deaths and over $1 billion in damages a year — but are also widespread, occurring in all 50 states. Compounding the hazards, these natural disasters often occur along with other similar natural phenomena, such as floods or earthquakes. [Read More]