how does the plate boundaries theory affect people?explain
Earthquake - During an earthquake, the lithosphere breaks suddenly along a fault. Slip of a few millimeters to tens of meters typically occurs along the fault during an earthquake. Repeated earthquakes can thus cause significant movement of the crust on one side of a fault relative to the crust on the other side.
As shown in the figure, most (~90%) earthquakes are concentrated in remarkably narrow belts that connect to form a spider web of fault zones that divide the lithosphere into nearly aseismic regions called plates. A key postulate of the theory of plate tectonics is that plates are internally rigid, meaning that over geologic time, they retain their shape because they do not deform. The concentration of earthquakes along narrow fault zones between the plates tells us that plates move relative to each other and that the motion is often focused along narrow boundaries between them.
Plate boundaries are defined as the fault zones that separate the rigid interiors of plates. Many plate boundaries are narrow, particularly seafloor spreading centers and transform faults (discussed farther below). However, the following figure clearly shows that earthquakes in continents are often distributed over a broader region than in oceanic crust. This occurs because the strength of continental lithosphere as a function of depth differs significantly from that of oceanic lithosphere, which tends to be strong and homogeneous from top to bottom. Plate boundaries within continents are typically wide. For example, the collision zone between the Indian and Eurasian plates (30-45N, 60-100E) extends some 1500 km in areas. Even though continental earthquakes are often widely distributed, large areas are aseismic and define rigid plate interiors.
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how does the plate boundaries theory affect people?explain
Earthquake - During an earthquake, the lithosphere breaks suddenly along a fault. Slip of a few millimeters to tens of meters typically occurs along the fault during an earthquake. Repeated earthquakes can thus cause significant movement of the crust on one side of a fault relative to the crust on the other side.
As shown in the figure, most (~90%) earthquakes are concentrated in remarkably narrow belts that connect to form a spider web of fault zones that divide the lithosphere into nearly aseismic regions called plates. A key postulate of the theory of plate tectonics is that plates are internally rigid, meaning that over geologic time, they retain their shape because they do not deform. The concentration of earthquakes along narrow fault zones between the plates tells us that plates move relative to each other and that the motion is often focused along narrow boundaries between them.
Plate boundaries are defined as the fault zones that separate the rigid interiors of plates. Many plate boundaries are narrow, particularly seafloor spreading centers and transform faults (discussed farther below). However, the following figure clearly shows that earthquakes in continents are often distributed over a broader region than in oceanic crust. This occurs because the strength of continental lithosphere as a function of depth differs significantly from that of oceanic lithosphere, which tends to be strong and homogeneous from top to bottom. Plate boundaries within continents are typically wide. For example, the collision zone between the Indian and Eurasian plates (30-45N, 60-100E) extends some 1500 km in areas. Even though continental earthquakes are often widely distributed, large areas are aseismic and define rigid plate interiors.