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Quaternary geology and liquefaction susceptibility, Napa, California 1:100,000 quadrangle: A digital database


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2013-05-16 14:07:58


This Open-File report consists of a digital geologic map database and associated digital plot files and text files, revised from a hard copy by Sowers and others (1995). This digital map database provides current information on Quaternary geology and liquefaction susceptibility of the Napa, California, 1:100,000 quadrangle. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey.


Point of Contact :
Janet M. Sowers
Process Contact :
Jennifer Lenz
Distributor :
USGS Information Services
Metadata Contact :
Peter N Schweitzer
Originator :
Janet M. Sowers, Jay S. Noller, William R. Lettis

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Earthquake-induced ground failures such as liquefaction have historically brought loss of life and damage to property and infrastructure. Observations of the effects of historical large-magnitude earthquakes show that the distribution of liquefaction phenomena is not random. Liquefaction is restricted to areas underlain by loose, cohesionless sands and silts that are saturated with water. These areas can be delineated on the basis of thorough geologic, geomorphic, and hydrologic mapping and map analysis. Once potential liquefaction zones are delineated, appropriate public and private agencies can prepare for and mitigate seismic hazard in these zones. In this study, we create a liquefaction susceptibility map of the Napa 1:100,000 quadrangle using Quaternary geologic mapping, analysis of historical liquefaction information, groundwater data, and data from other studies.
PDF representation of the Quaternary geologic map sheet.
PDF representation of the Quaternary geologic map sheet.




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Added to Sciencebase on Sat Nov 16 14:10:32 MST 2013 by processing URL <b>metadata.xml</b> in item <a href=""></a> <br />

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