Catalog of Nevada earthquakes, 1852-1960

Abstract Nevada earthquakes for the period from about 1852 to 1961 are tabulated on I.B.M. punch cards. During this period 1,173 events with Nevada epicenters were felt, 586 others with Richter magnitudes above 4.0 were recorded and were probably felt by some residents, and approximately 220 were reported in nonspecific terms (e.g. “several aftershocks were felt”). High seismicity of this region is indicated by the fact that on an equal-area basis, during the period 1934-1960, Nevada has had the highest incidence of earthquakes per unit area of any of the conterminous Western States. The seismic activity shows a distinct tendency, statistically inadequate, for a 20-year cycle of activity, with peaks at about 1852(?), 1872, 1894, 1916, 1932-1933, and 1954. The general increase in number of events reported each year correlates well with the increase in Nevada population, but is probably modified by the development of: increasingly sophisticated methods of recording, spacing of seismographic stations, more intensive earthquake investigations of the United States Coast and Geodetic Survey, and changing population density and distritution. A method is developed for correlating between Richter magnitude, earthquake intensity, and size of felt area. This permits estimation of earthquake magnitude for shocks that pre-date instrumental methods of recording. The areal distribution of the earthquake epicenters does not indicate a noticeable change in pattern during this brief historic period, except possible recent intensification of activity near Lake Mead. Seismic activity is concentrated in three zones: a Western Nevada-Eastern California Zone which includes the northern Sierra Nevada frontal faults, Fish Lake Valley-Furnace Creek-Death Valley fault systems and Walker Lane; a 118° Meridian Seismic Zone which contains most of the historic surface faults; and a weak Southern Nevada Transverse Zone that includes the Lake Mead activity.