What is Liquefaction and how likely will it occur near Calistoga?
Liquefaction occurs when young, Sandy water saturated deposits are shaken strongly during earthquakes. These deposits lose their strength and behave like a liquid quicksand. Buildings and other structures can be damaged when their foundations sink into these soupy sands. The liquefaction state maps depict zones where site specific studies are required for new construction. These bones maps are also used in real estate transactions- sellers of properties within a "zone of required investigation" must disclose that fact to prospective buyers. Maps of liquefaction hazard are used to show how the hazard differs from place to place, the like hood of liquefaction in different earthquake scenarios, and to define hazards zones for regulatory purposes. Damaged occurs to the surface layer when it is moved, including fissures and scraps. The bay area is crossed by many active faults. Earthquakes caused by rupturing of longer faults or fault segments will cause strong shaking in several countries.