Which term refers to the continental margin near an area of lithospheric plate convergence, also known as the Pacific-type Margin?

Which term refers to the continental margin near an area of lithospheric plate convergence, also known as the Pacific-type Margin?

• A. Passive Margin
• B. Active Margin
• C. Continental Margin
• D. Abyssal Hill

Answer: (B)

Active margins occur where a continental plate and an oceanic plate converge and one sinks beneath the other. This subduction drives intense tectonic activity at the edge of the continent: deep trenches, volcanic arcs, strong earthquakes, and rapid deformation of the crust. The Pacific-type margin is a classic example of this, since many of the world’s subduction zones hug the rim of the Pacific Ocean, creating narrow, dynamic margins with significant geological activity. In contrast, passive margins lie away from plate boundaries, with little tectonic disruption, broad continental shelves, thick sediment buildup, and very gentle deformation. A continental margin is a broad term that can describe either active or passive margins, while an abyssal hill is a seafloor feature, not a margin type. Thus, the term that best fits a margin at a convergent boundary, the Pacific-style setting, is the active margin.

Active margins occur where a continental plate and an oceanic plate converge and one sinks beneath the other. This subduction drives intense tectonic activity at the edge of the continent: deep trenches, volcanic arcs, strong earthquakes, and rapid deformation of the crust. The Pacific-type margin is a classic example of this, since many of the world’s subduction zones hug the rim of the Pacific Ocean, creating narrow, dynamic margins with significant geological activity.

In contrast, passive margins lie away from plate boundaries, with little tectonic disruption, broad continental shelves, thick sediment buildup, and very gentle deformation. A continental margin is a broad term that can describe either active or passive margins, while an abyssal hill is a seafloor feature, not a margin type. Thus, the term that best fits a margin at a convergent boundary, the Pacific-style setting, is the active margin.