Divergent boundary

Definition

A divergent boundary is a tectonic plate boundary where two plates move away from each other, resulting in the creation of new oceanic crust as magma rises to the surface. This process is crucial in the formation of mid-ocean ridges and rift valleys, highlighting the dynamic nature of Earth's lithosphere and its role in shaping geological features. Divergent boundaries not only contribute to seafloor spreading but also influence seismic activity and geological processes within the Earth's interior.

5 Must Know Facts For Your Next Test

1. Divergent boundaries are primarily found along mid-ocean ridges, such as the Mid-Atlantic Ridge, where new oceanic crust is continuously formed.
2. As tectonic plates separate, they can create gaps that allow magma to rise, resulting in volcanic activity associated with these boundaries.
3. Seismic activity is common at divergent boundaries, although earthquakes tend to be less powerful compared to those at convergent boundaries.
4. Rift valleys can form on land when continental plates diverge, as seen in the East African Rift system.
5. Divergent boundaries play a key role in the rock cycle, contributing to the renewal and recycling of Earth's lithosphere.

Review Questions

• How does seafloor spreading occur at divergent boundaries and what implications does it have for ocean basin formation?
  • Seafloor spreading occurs at divergent boundaries where tectonic plates move apart, allowing magma to rise from the mantle and solidify at the ocean floor. This process creates new oceanic crust and gradually widens ocean basins over time. The continuous movement of plates not only shapes the seafloor but also influences global ocean currents and climate patterns.
• Compare and contrast divergent boundaries with convergent boundaries in terms of their geological features and processes.
  • Divergent boundaries are characterized by the movement of tectonic plates away from each other, leading to the formation of mid-ocean ridges and new crust through seafloor spreading. In contrast, convergent boundaries involve plates moving toward each other, resulting in subduction zones where one plate is forced beneath another, leading to mountain building or volcanic activity. While divergent boundaries generally produce less intense seismic activity, convergent boundaries are often associated with powerful earthquakes and significant geological transformations.
• Evaluate the long-term impacts of divergent boundaries on Earth's geological evolution and continental configurations.
  • Divergent boundaries significantly impact Earth's geological evolution by continuously reshaping continents and ocean basins through processes like seafloor spreading. Over millions of years, these boundaries facilitate the drift of continents away from each other, altering geographical configurations and influencing ecosystems. Additionally, they contribute to volcanic activity and earthquake formation, which play critical roles in shaping landforms and affecting climate patterns throughout Earth's history.

Related terms

Mid-Ocean Ridge: An underwater mountain range formed by plate tectonics, where new oceanic crust is created at divergent boundaries.

Seafloor Spreading:

The process by which new oceanic crust is formed at divergent boundaries, pushing older crust away from the ridge.

Rift Valley: A lowland region formed by the divergence of tectonic plates, often found on continents as they split apart.