Earth Science Week Classroom Activities

Exploring the Age of the Seafloor

Activity Source: Written by AGI based on lessons by the International Ocean Discovery Program

The Earth’s surface is made up of tectonic plates that fit together something like puzzle pieces, forming fault lines where they meet. There are seven major plates and some smaller ones. These plates move apart at divergent boundaries and collide at convergent boundaries. At transform boundaries, the plates slide past each other.

Plates

Materials

  • 2 pencils
  • 2m of toilet paper (two 1 m sections)
  • tape
  • multiple colors of confetti, sequins, or sprinkles, separated by color

Procedure

  1. Examine the Age of the Seafloor map on the front of the 2024 ESW poster and a map of the major tectonic plates. Identify the type of boundary at which new crust is made and explain your reasoning using evidence from the maps. Also, make observations of any patterns or trends you notice.
  2. Construct a seafloor spreading model using toilet paper, pencils, and confetti to help explain the map and explore other related data:

  • Tape one end of a 1 m long piece of toilet paper to a pencil, then roll the toilet paper around the pencil. Repeat with a second piece of toilet paper on another pencil. Position them to model sea floor spreading.

  • While one student holds the pencils in place, another student will gently pull the ends of the toilet paper in opposite directions.

  • A third student will sprinkle one color of confetti over the center of the model, making sure that the confetti lands on both sides of the ridge. (If students are working in groups, determine in what order the various colors of confetti should be used so that each group has the same order.)

  • The student sprinkling will switch colors every three seconds as the plates spread. The two sides of the ridge should have the same sequence of colors, starting at the ridge and moving outward.

  1. Explore the interactive version of the seafloor map online and other NOAA deep sea resources on the 2024 ESW Resources page.

  2. How do you think scientists know the age of the seafloor? Learn more at https://bit.ly/ScientificOceanDrilling