Key Idea.
Section 1
Divergent Process and New Rock
At a divergent boundary, two tectonic plates move away from each other. As they separate, a gap opens up, exposing the hot mantle below.
Material from the mantle rises into this gap. Because it is moving away from the Earth's hot interior, this material cools and hardens into solid rock. This process continuously adds new material to the edges of the separating plates.
Section 2
Seafloor Spreading as a Mechanism
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.
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Section 1
Divergent Process and New Rock
At a divergent boundary, two tectonic plates move away from each other. As they separate, a gap opens up, exposing the hot mantle below.
Material from the mantle rises into this gap. Because it is moving away from the Earth's hot interior, this material cools and hardens into solid rock. This process continuously adds new material to the edges of the separating plates.
Section 2
Seafloor Spreading as a Mechanism
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.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter