Question

The largest earthquakes along western North America are due to subduction beneath the continent. They include _________.

a) San Andreas earthquakes
b) Rift earthquakes
c) Thrust earthquakes
d) Cascadia subduction zone earthquakes

Answer 1

The largest earthquakes in western North America due to subduction are the d. Cascadia subduction zone earthquakes. These earthquakes occur at the subduction zone where the Juan de Fuca Plate goes beneath the North American Plate, unlike the San Andreas Fault's transform movements.

Step-by-step explanation:

The largest earthquakes along western North America that are due to subduction beneath the continent include d) Cascadia subduction zone earthquakes. The Cascadia subduction zone is where the Juan de Fuca Plate is being forced beneath the North American Plate, leading to significant earthquake activity. In contrast, the San Andreas Fault, which forms the tectonic boundary between the Pacific Plate and the North American Plate, is characterized by transform fault movements, where plates slide sideways past each other.

All along the subduction zone, earthquakes and volcanoes indicate where the subducting slab meets the overriding slab. Subduction zone earthquakes are typically more powerful and can cause considerable damage, as evidenced by historic events such as the 2004 Sumatra earthquake and tsunami.

The Ring of Fire, which circles the Pacific Ocean, is home to many subduction zones, leading to frequent seismic and volcanic activity.