Hydrologic effects associated with the January 17, 1994 Northridge, California, earthquake

E.G. Quilty; C. D. Farrar; D. L. Galloway; S. N. Hamlin; R. J. Laczniak; E.A. Roeloffs; M.L. Sorey; D.E. Woodcock

doi:10.3133/ofr95813

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Hydrologic effects associated with the January 17, 1994 Northridge, California, earthquake

E.G. Quilty·C. D. Farrar·D. L. Galloway·S. N. Hamlin·R. J. Laczniak·E.A. Roeloffs·M.L. Sorey·D.E. Woodcock

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Abstract

This report compiles hydrologic observations in southern California associated with the 1994 Mw = 6.7 Northridge, California earthquake. In southern California, the largest ground water level change was a drop of 52 cm at Crystalaire. Most of the steplike water-level changes recorded following the Northridge earthquake agreed in direction with the sign of the calculated coseismic volume strain field. A spring discharge increase at Southern Pacific Springs was reported to have preceded the earthquake by several days. Outside of southern California, water-level changes were also observed, but are not consistent in sign or size with the static strain field of the earthquake sequence.

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Source-reported bounding extent: 31.615965936476076° to 43.100982876188546° latitude; -125.41992187499999° to -113.99414062499999° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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E.G. Quilty, C. D. Farrar, D. L. Galloway, S. N. Hamlin, R. J. Laczniak, E.A. Roeloffs, M.L. Sorey, D.E. Woodcock. 1995. Hydrologic effects associated with the January 17, 1994 Northridge, California, earthquake. https://doi.org/10.3133/ofr95813

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