Maximum magnitudes along many normal faults are even more limited because many of them are located along spreading centers, as in Iceland, where the thickness of the brittle layer is only about six kilometres (3.7 mi). Reverse faults
Reverse faults occur in areas where the crust is being shortened such as at a convergent boundary. Reverse faults, particularly those along convergent plate boundaries, are associated with the most powerful earthquakes, megathrust earthquakes, including almost all of those of magnitude 8 or more. Megathrust earthquakes are responsible for about 90% of the total seismic moment released worldwide. Strike-slip faults
Strike-slip faults are steep structures where the two sides of the fault slip horizontally past each other; transform boundaries are a particular type of strike-slip fault. Strike-slip faults, particularly continental transforms, can produce major earthquakes up to about magnitude 8. Strike-slip faults tend to be oriented near vertically, resulting in an approximate width of 10 km (6.2 mi) within the brittle crust. Thus, earthquakes with magnitudes much larger than 8 are not possible. In addition, there exists a hierarchy of stress levels in the three fault types. Thrust faults are generated by the highest, strike-slip by intermediate, and normal faults by the lowest stress levels. This can easily be understood by considering the direction of the greatest principal stress, the direction of the force that "pushes" the rock mass during the faulting.
Ground rupture is a visible breaking and displacement of the Earths surface along the trace of the fault, which may be of the order of several meters in the case of major earthquakes. Ground rupture is a major risk for large engineering structures such as dams, bridges, and nuclear power stations and requires careful mapping of existing faults to identify any that are likely to break the ground surface within the life of the structure. Soil liquefaction
Soil liquefaction occurs when, because of the shaking, water-saturated granular material (such as sand) temporarily loses its strength and transforms from a solid to a liquid. Soil liquefaction may cause rigid structures, like buildings and bridges, to tilt or sink into the liquefied deposits. For example, in the 1964 Alaska earthquake, soil liquefaction caused many buildings to sink into the ground, eventually collapsing upon themselves. Human impacts
Physical damage from an earthquake will vary depending on the intensity of shaking in a given area and they type of population. Undeserved and developing communities frequently experience more severe impacts (and longer lasting) from a seismic event compared to well developed communities. Impacts may include:

Injuries and loss of life
Damage to critical infrastructure (short and long term)
Roads, bridges and public transportation networks
Water, power, swear and gas interruption
Communication systems
Loss of critical community services including hospitals, police and fire
General property damage
Collapse or destabilization (potentially leading to future collapse) of buildingsWith these impacts and others, the aftermath may bring disease, lack of basic necessities, mental consequences such as panic attacks, depression to survivors, and higher insurance premiums.