Ground Rupture
soft
(soft) / (hard) sediments usually host patterned ground ruptures rather than single fault traces.
deformation
It consists of horizontal and/or vertical displacement along the fault trace and folding or bending of the adjacent area.
strike-slip fault
It involves a dominantly horizontal shifting of the ground. This is when the horizontal component of displacement is larger than the vertical one. It has a steeper fault plane.
normal fault
It involves mainly downward movement of the ground across the fault called the hanging wall.
thrust fault
It involves mainly upward movement of the hanging wall. In any type of faulting, opposite blocks simply slide past each other along the fault plane. No opening is involved.
footwall
It is the block positioned below the fault.
hanging wall
It is the block positioned over the fault.
setback
It refers to the distance from the fault trace that is considered safe from the effects of ground rupture. It may differ for each type of building use.
more
It takes a lot (less) / (more) amount of stress to form new faults and generate earthquakes within stronger parts of the lithosphere.
faulting
It's the rock failure that involves the slipping of lithosphere blocks past each other. It tends to occur along zones of weakness such as old or pre-existing fault, fractures, etc.
inversely
The degree of danger to man-made structures is (directly) / (inversely) proportional to distance to the ground rupture.
long, along, narrow, wider
The factors affecting the characteristics of ground ruptures determine how (short) / (long) ground ruptures are, how and by how much the earth's surface breaks (along) / (within) ground ruptures, and whether deformation is limited along the (wide) / (narrow) fault trace or affects a (narrower) / (wider) zone.
type of fault movement, inclination of the fault plane, depth and nature of sedimentary rocks
The factors affecting the characteristics of ground ruptures include...
avoidance of active fault trace and of the high-risk danger zone when planning a construction
The key to minimize the effects of ground ruptures are...
large
The lithosphere breaks when its strength is overcome by the (small) / (large) amount of stress applied.
left-lateral; right-lateral
The two types of strike-slip fault are distinguished from each other by the sense of motion of part of the ground located on opposite side of the fault. What are these?
ground ruptures
These are earthquake faults that have reached the surface. No opening or fissuring happens during movement of the fault, so it should remain closed.
liquefaction cracks and fissures
These are formed on soft ground by the intense shaking during an earthquake.
more recently developed active faults
These faults form wider, less distinct deformation zones.
well-established active faults
These faults tend to develop more distinct ground rupture zones.
active faults
These have been found to have moved under the current stress field and have caused earthquake during historical times and the recent geologic past. They're quite dangerous.
earthquakes
These occur by the sudden motion along lithospheric breaks called faults.
gently
Thrust faults are more (gently) / (harshly) inclined and so rupture propagation toward the surface is made more difficult by gravity and the load of overlying rocks.