Mid-ocean ridge

Definition

A mid-ocean ridge is an underwater mountain range formed by tectonic plates diverging and new oceanic crust being created through volcanic activity. These ridges are significant features of the ocean floor, serving as sites of seafloor spreading where magma rises to create new crust and drive the movement of tectonic plates, connecting to larger geological processes and plate interactions.

5 Must Know Facts For Your Next Test

1. Mid-ocean ridges are the longest mountain ranges in the world, stretching over 65,000 kilometers across the globe.
2. The formation of mid-ocean ridges is closely linked to the process of mantle convection, where heat from the Earth's interior causes magma to rise and create new crust.
3. The East Pacific Rise and the Mid-Atlantic Ridge are two major examples of mid-ocean ridges, with each displaying unique geological features and spreading rates.
4. Hydrothermal vents found along mid-ocean ridges support unique ecosystems that thrive on chemosynthesis, relying on chemicals released by the Earth's interior instead of sunlight for energy.
5. Mid-ocean ridges play a crucial role in the global carbon cycle, as they facilitate the exchange of carbon between the ocean and atmosphere through geological processes.

Review Questions

• How do mid-ocean ridges contribute to our understanding of seafloor spreading?
  • Mid-ocean ridges are central to the concept of seafloor spreading, which describes how new oceanic crust is formed as tectonic plates diverge. At these ridges, magma rises from the mantle, solidifying to create new crust as older crust is pushed away. This process not only helps explain how continents drift apart over time but also provides insights into the geological activity occurring beneath ocean surfaces.
• Discuss the relationship between mid-ocean ridges and divergent plate boundaries in terms of geological activity.
  • Mid-ocean ridges are directly associated with divergent plate boundaries, where two tectonic plates move apart from each other. This movement allows magma from the mantle to rise and create new oceanic crust at the surface. The geological activity at these boundaries often results in earthquakes and volcanic eruptions, demonstrating how dynamic Earth’s geology can be in these regions.
• Evaluate the ecological significance of hydrothermal vents located along mid-ocean ridges.
  • Hydrothermal vents found along mid-ocean ridges have immense ecological significance as they support unique ecosystems that rely on chemosynthesis rather than photosynthesis. Organisms such as tube worms and certain bacteria thrive in these extreme environments, utilizing chemicals emitted from the Earth's interior for energy. This not only highlights the adaptability of life but also emphasizes how mid-ocean ridges contribute to biodiversity in some of the most inhospitable places on Earth.

Related terms

Seafloor Spreading: The process by which new oceanic crust is formed at mid-ocean ridges as magma rises from the mantle, causing the ocean floor to gradually widen.

Tectonic Plates: Massive slabs of the Earth's lithosphere that move and interact at their boundaries, leading to geological phenomena such as earthquakes and volcanic activity.

Divergent Boundary: A type of plate boundary where two tectonic plates move away from each other, leading to the formation of new crust at mid-ocean ridges.