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'''Soil Liquefaction''' is the process by which saturated, unconsolidated soil or sand is converted into a suspension.  It is commonly observed in [[quicksand]], [[quick clay]], [[turbidity current]]s, and as a result of [[earthquake]] shock in unconsolidated sediments. It can be caused when flowing water reduces the [[friction]] between sand particles (as from an underground spring), or when a sudden change in pressure or repeated shock acting on water saturated or supersaturated [[sediment]]s (as in an earthquake). Although the effects of [[liquefaction]] had been observed and understood for years, it was dramatically brought to the attention of [[Engineering|engineer]]s and seismologists in 1964 during the [[Niigata, Niigata|Niigata, Japan]] and [[Alaska]] earthquakes. It was a major factor in the destruction in [[San Francisco|San Francisco's]] [[Marina District]] during the [[1989]] [[Loma Prieta earthquake]].

'''Soil Liquefaction''' is the process by which saturated, unconsolidated soil or sand is converted into a suspension.  It is commonly observed in [[quicksand]], [[quick clay]], [[turbidity current]]s, and as a result of [[earthquake]] shock in unconsolidated sediments. It can be caused when flowing water reduces the [[friction]] between sand particles (as from an underground spring), or when a sudden change in pressure or repeated shock acting on water saturated or supersaturated [[sediment]]s (as in an earthquake). Although the effects of [[liquefaction]] had been observed and understood for years, it was dramatically brought to the attention of [[Engineering|engineer]]s and seismologists in 1964 during the [[Niigata, Niigata|Niigata, Japan]] and [[Alaska]] earthquakes. It was a major factor in the destruction in [[San Francisco|San Francisco's]] [[Marina District]] during the 1989 [[Loma Prieta earthquake]].

== Liquefaction in earthquakes ==

== Liquefaction in earthquakes ==

{{Main|Turbidity current}}

{{Main|Turbidity current}}

Submarine landslides are [[turbidity current]]s and consist of a flow of water saturated sediments flowing downslope. An example occurred [[18 November]] [[1929]], when an earthquake struck the [[continental slope]] off the coast of [[Newfoundland]]. Minutes later, [[transatlantic telephone cable]]s began breaking sequentially, farther and farther downslope, away from the [[epicenter]]. Twelve cables were snapped in a total of 28 places. Exact times and locations were recorded for each break. Investigators suggested that a 60-mile-per-hour (100 km/h) submarine ''landslide'' or turbidity current of water saturated sediments swept 400 miles (600 km) down the [[continental slope]] from the earthquake&#8217;s epicenter, snapping the cables as it passed.<ref>Bruce C. Heezen and Maurice Ewing, &#8220;Turbidity Currents and Submarine Slumps, and the 1929 Grand Banks Earthquake,&#8221; American Journal of Science, Vol. 250, December 1952, pp. 849&#8211;873.</ref>

Submarine landslides are [[turbidity current]]s and consist of a flow of water saturated sediments flowing downslope. An example occurred 18 November 1929, when an earthquake struck the [[continental slope]] off the coast of [[Newfoundland]]. Minutes later, [[transatlantic telephone cable]]s began breaking sequentially, farther and farther downslope, away from the [[epicenter]]. Twelve cables were snapped in a total of 28 places. Exact times and locations were recorded for each break. Investigators suggested that a 60-mile-per-hour (100 km/h) submarine ''landslide'' or turbidity current of water saturated sediments swept 400 miles (600 km) down the [[continental slope]] from the earthquake&#8217;s epicenter, snapping the cables as it passed.<ref>Bruce C. Heezen and Maurice Ewing, &#8220;Turbidity Currents and Submarine Slumps, and the 1929 Grand Banks Earthquake,&#8221; American Journal of Science, Vol. 250, December 1952, pp. 849&#8211;873.</ref>

==External links==

==External links==