Plate tectonics provide a comprehensive explanation for the global distribution of earthquakes and volcanic activities. Here’s how plate tectonics theory explains these phenomena:

1. Plate Boundaries:
   • Most earthquakes and volcanic eruptions occur at the boundaries between Earth’s tectonic plates.
   • At convergent plate boundaries, where two plates collide, one plate typically subducts (or is pushed) under the other, leading to intense seismic and volcanic activity along the subduction zone.
   • At divergent plate boundaries, where plates are moving apart, molten magma rises to fill the gap, creating mid-ocean ridges and volcanic activity.
   • Transform plate boundaries, where plates slide past each other, also experience significant earthquake activity.
2. Subduction Zones:
   • At subduction zones, the downgoing plate is subjected to intense stress and friction, generating deep earthquakes as the plate bends and descends into the Earth’s mantle.
   • The melting and dehydration of the subducting plate also leads to the formation of volcanoes in the overlying plate, creating volcanic arcs like the Pacific Ring of Fire.
3. Mid-Ocean Ridges:
   • At mid-ocean ridges, where plates are moving apart, new oceanic crust is continuously being formed, generating a high level of seismic activity along the ridge axis.
   • Volcanic activity is also common at mid-ocean ridges, as magma wells up to fill the gap between the diverging plates.
4. Transform Faults:
   • Transform faults, where plates slide past each other, experience significant earthquake activity due to the stresses and friction along the fault line.
   • While transform faults are not typically associated with volcanic activity, they can sometimes be the site of limited volcanic eruptions.
5. Intraplate Regions:
   • Although most earthquakes and volcanoes are concentrated at plate boundaries, some seismic and volcanic activity can also occur within the interior of tectonic plates, known as intraplate regions.
   • These intraplate events are often associated with hotspots, mantle plumes, or other geological phenomena that can cause localized volcanic and seismic activity.