Seafloor Spreading as a Mechanism
Seafloor spreading is the mechanism by which new oceanic crust is created at divergent plate boundaries, where magma rises from the mantle, hardens, and pushes older rock outward like a conveyor belt. Covered in Amplify Science (California) Grade 7, Chapter 2: Understanding Plate Boundaries, this process explains how mantle material actively drives the movement of tectonic plates.
Key Concepts
The process at divergent boundaries creates a conveyor belt effect known as seafloor spreading . As new rock forms at the boundary, it pushes the older rock outward.
This confirms that the mantle is the source of new plate material. The rising and hardening of the mantle not only fills the gap but actively contributes to the movement of the plates, forcing them further apart.
Common Questions
What is seafloor spreading?
Seafloor spreading is the process where new oceanic crust forms at divergent boundaries as magma rises from the mantle, solidifies, and pushes older crust outward, acting like a conveyor belt.
How does seafloor spreading move tectonic plates?
As new rock forms at mid-ocean ridges, it pushes older rock to the sides. This continuous creation of new crust actively forces the tectonic plates further apart.
What is the connection between seafloor spreading and plate tectonics?
Seafloor spreading is the mechanism that drives divergent plate movement. The rising mantle material fills gaps between separating plates and pushes them apart, confirming that the mantle is the source of plate motion.
Where is seafloor spreading covered in Amplify Science Grade 7?
Seafloor spreading is taught in Amplify Science (California) Grade 7, Chapter 2: Understanding Plate Boundaries.