Earth Science Week Classroom Activities

Karst Topography Model

Activity Source:

National Park Service (www.nps.gov/geology) and Forest Service (www.fs.fed.us/geology/resources).
Adapted with permission.from the U.S. Geological Survey Open-file Report 97-536-A
Karst Topography Computer animations and paper model, 1997

Did you know that a quarter of the world’s population gets drinking water from karst aquifers? Karst is the type of landscape that forms by dissolution of carbonate rocks (limestone, dolomite) or other highly soluble rocks such as evaporates (gypsum and rock salt). Karst includes caves, sinkholes, sinking streams, and springs. Karst environments are vulnerable to groundwater contamination. Understanding groundwater flow in karst terrains is critical for safe drinking water.

Karst and caves are important features of our nation’s geologic heritage. About 20 percent of the United States is underlain by karst. Caves are natural laboratories with constant temperature and humidity preserving fossils, minerals, ecosystems, and records of past climates. Today they also provide recreation opportunities for visitors.

In this activity, you will construct a 3-D paper model to explore a karst system and how water flows through it.

Materials

• Scissors
• Glue or tape
• Color pencils, crayons, or markers
• Cave patterns (pages 4–6 from the Karst Topography Paper Model Student Page at https://www.nps.gov/subjects/caves/upload/StudentPages_karsttopography_508c.pdf)
• Computer with internet access and printer

Procedure

1. Visit https://www.nps.gov/subjects/caves/karst-topography-model.htm. Go to the Downloads section and read the Karst Topography Paper Model Reading Guide to learn about caves and karst. Answer the pre-activity questions.

2. Go to the Karst Topography Paper Model Student Page (https://www.nps.gov/subjects/caves/upload/StudentPages_karsttopography_508c.pdf). Print the pages 4–6.

3.Color the cave patterns 1,2, and 3 (on pages 4–6). Select colors that are realistic to show a real karst environment. Find images of caves and karst at the National Park Service website to use for clues (https://www.nps.gov/subjects/caves/park-resources.htm)

4. To build your model, follow steps 1–9 on the Cave Assembly instructions on pages 7–9. Carefully cut, fold, glue, and assemble the pieces as directed. Use the “Helpful Hints for Constructing Model” (pages 10–11) to assist you.

5. Use your karst model to answer:

• Look through the cave opening. Describe what features you see.

• Describe the relationship between the sinking stream and the sinkhole as the waters drains through the bedrock. What direction is the water flowing?

• As the water flows through the cave what features are forming on the cave walls?

• A truck carrying fertilizer crashed near the stream within a few miles from this karst feature. Fertilizer spilled into the stream and was carried towards the sinkhole. What effect will this have on the karst aquifer? Would you want to drink the water from the aquifer?

6. Now that you know more about caves and karst explore a National Park that contains karst near to where you live.