Actvity Summary: Students will analyze real-world data collected from the Deep-Sea Drilling Project to describe evidence of seafloor spreading, and graph and use slope analysis to determine the relationship between distance from the spreading center and age of the sediments.

This lesson focuses on determining the age of oceanic crust at ocean ridges using nannofossils. Students will model seafloor spreading, examine maps of the Mid Atlantic ridge, and interpret and graph data from an early leg (expedition) of the scientific ocean drilling program understand the evidence that supports seafloor spreading. This lesson will help students understand how the age of oceanic crust is determined; it can lead into lessons on evidence for the rate of seafloor spreading.

This lesson has been revised and updated based on Nannofossils Reveal Seafloor Spreading Truth.