Surface Processes: Soils

Karst, Sinkholes, and Human Activity

Scientists, engineers, and others create geologic maps to determine the best places for people to settle, build, farm, and use land in a variety of ways. They also use geologic maps to monitor the ways that human activity might be changing the land itself over time.In this activity, you will examine geologic maps — and other maps — to consider the relationship between karst and human activity.


When it comes to slipping, sliding, and stability in soils, the key word is “liquefaction.”

During an event like an earthquake, liquefaction is the process by which saturated soil behaves like a liquid. This can be problematic, as a liquid soil loses structure and can cause buildings to sink, foundations to crack, and soil to slide down slopes all at once.

How does the type of soil affect how much a house will sink or shift during an earthquake? Conduct an experiment to test your ideas!

Mapping Your Soil

The key properties of soil (physical, biological, and chemical) determine recreation, crop production, range, water/erosion conservation, forestry, and engineering uses of the soil. Soil surveys help us understand how soils differ and how they behave under various land management systems. The heart of a soil survey is the soil map showing the spatial distribution and variability of soils on the landscape.

Measuring Permeabilities of Soil, Sand, and Gravel

This investigation will help you to learn that different geologic materials have different characteristics.

Nitrogen Connection

All biological organisms require certain nutrients to live. Plants require carbon, hydrogen, and oxygen from air and water, as well as nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, copper, zinc, nickel, chloride, boron, and molybdenum from soil. Animals require a few others. Conversions and transformations of nutrients in the environment result from chemical reactions, biological activity, or both.

Particle Size and Oil Production

What factors affect how easily a fluid can move through sediments? How is this flow rate connected to oil production? In this investigation, you will explore the permeabilities of different materials. You will then use your observations to determine what affects permeability and how this might relate to oil production.

Rain and Soil

When it rains, much of the water drains directly into the ground. But why?

Reclaiming a Mine Site

Mined land is reclaimed for future use. The objective of this activity is to investigate how plants will grow on a reclaimed landscape. Over a period of days, you will learn how overburden is incorporated into the landscape after it has been removed during the mining process.Before beginning, discuss vocabulary terms: overburden, stockpile, grading, soil types, seeding, stability, seed germination, nutrients, closure planning, and reclamation.

Soil Color and Redox Chemistry

Are soils like M&Ms™? Yes! Find out more in this awesome activity provided by the Soil Science Society of America.

Soil Moisture

Where is the water in soil? Solids, liquids, and gasses, the three phases of matter, are always present in soil. Small mineral and organic particles comprise the solid fraction, and there are spaces (pores) between the solid particles. Some pores are large, and others are very small. Air and water, the gas and liquid phases, exist in the pores. The size of the soil particles and pores affects how much water a soil can hold, and how that water moves through the soil.


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