📚 Topic Summary
Mid-ocean ridges are underwater mountain ranges where new oceanic crust is formed. This process, called seafloor spreading, occurs as magma rises from the Earth's mantle to the surface at these ridges. As the magma cools, it solidifies, creating new crust that pushes the older crust away from the ridge. This continuous cycle of magma upwelling and crust formation is a key component of plate tectonics, constantly reshaping the Earth's surface. Think of it like a giant zipper opening up, with new material filling the gap!
This activity will let you model this process using simple materials to visualize how new crust is created and moves away from the mid-ocean ridge over time. It's a hands-on way to see how our planet constantly renews itself!
🌋 Part A: Vocabulary
Match the terms with their definitions:
| Term |
Definition |
| 1. Mid-Ocean Ridge |
A. The layer beneath the crust. |
| 2. Magma |
B. Molten rock beneath the Earth's surface. |
| 3. Lava |
C. An underwater mountain range where new crust forms. |
| 4. Mantle |
D. The process of new crust being created at mid-ocean ridges. |
| 5. Seafloor Spreading |
E. Molten rock that erupts onto the Earth's surface. |
🗺️ Part B: Fill in the Blanks
Use the words below to complete the paragraph:
(crust, ridge, magma, plates, mantle)
New oceanic ______ is formed at a mid-ocean ______. Here, ______ rises from the Earth's ______ and cools, solidifying to create new rock. This process pushes the tectonic ______ apart, contributing to seafloor spreading. As new material is added, older material moves away from the area.
🤔 Part C: Critical Thinking
Imagine the Earth stopped creating new crust at mid-ocean ridges. What do you think would happen to the Earth's surface over millions of years? Would the continents stay the same? Explain your reasoning.