Which boundary type is associated with trenches and earthquakes due to subduction?

Which boundary type is associated with trenches and earthquakes due to subduction?

• A. Divergent
• B. Transform
• C. Convergent
• D. Passive margin

Answer: (C)

Subduction happens at convergent boundaries when one tectonic plate dives beneath another, pulling the edge down and forming a deep ocean trench where the contact between plates is greatest. The slipping and sticking of the plates as they interact produces earthquakes that can occur along the subduction zone, often extending from the trench down into the mantle (the Wadati-Benioff zone). This same process also commonly drives volcanic activity on the overriding plate as fluids released from the descending slab melt mantle rocks. Divergent boundaries create ridges and new crust rather than trenches; transform boundaries produce earthquakes along faults with little or no trench formation; passive margins are not active subduction zones.

Subduction happens at convergent boundaries when one tectonic plate dives beneath another, pulling the edge down and forming a deep ocean trench where the contact between plates is greatest. The slipping and sticking of the plates as they interact produces earthquakes that can occur along the subduction zone, often extending from the trench down into the mantle (the Wadati-Benioff zone). This same process also commonly drives volcanic activity on the overriding plate as fluids released from the descending slab melt mantle rocks. Divergent boundaries create ridges and new crust rather than trenches; transform boundaries produce earthquakes along faults with little or no trench formation; passive margins are not active subduction zones.