Chapter 7.2 (Earthquake Evidence)

Ground-level Evidence
Vertical or horizontal changes may occur in ground level near a fault.  Abrupt (quick) changes may occur,  but sometimes change can occur slowly.  This is called CREEP.  Creep will eventually destroy buildings that are located on a fault.

Landscape Evidence
     Slides - rapid, falling movements of soil, debris, or rock.
     Large sections of mountains may slide.  (Very destructive)

     Scarps - a cliff caused by earth movement along a fault.

     Fissures - Long cracks in soil or rock

Earthquake Damage - the amount of damage caused is determined by:

• how close an earthquake is to a populated area
• the type of ground on which structures are built (buildings on soft, wet, loose soils will be greatly damaged.
• Building design
• Offshore earthquakes may cause a  tsunami (a giant ocean wave caused by earthquakes)

Earthquake Prediction

• Based on evidence of previous quakes
• Based on creep rates
• Based on lower water levels

Science and Society

• In earthquake prone areas people develop disaster plans
• Building codes and zoning laws reduce risk