5. Most earthquakes are shallow. Use the concepts of elastic and ductile deformation to explain this fact?

Most earthquakes occur at shallow depths because the Earth's crust primarily exhibits elastic deformation, where rocks can store and release energy quickly when subjected to stress. When the accumulated stress exceeds the strength of the rocks, they fracture, resulting in an earthquake. In contrast, deeper layers of the Earth tend to exhibit ductile deformation, where rocks deform plastically and do not break as easily, leading to fewer seismic events in those regions. Thus, the elastic behavior of the shallow crust is the primary reason for the prevalence of shallow earthquakes.