Publications

Sediments collected for bridge foundation studies at southern San Francisco Bay, Calif., record estuaries that formed during Sangamon (100,000 years ago) and post-Wisconsin (less than 10,000 years ago) high stands of sea level. The estuarine deposits of Sangamon and post-Wisconsin ages are separated by alluvial and eolian deposits and by erosional unconformities and surfaces of...

A total of 1,075 earthquakes occurred in the Pahute Mesa area with 2.5≤ML≤4.9 during the period October 28, 1975, to June 28, 1976. The majority of these earthquakes are aftershocks of the nuclear events, Kasseri, Inlet, Muenster, Fontina, Cheshire, Estuary, Colby, and Pool (5.8≤ML≤6.3). Smaller nuclear events (ML≤5.5) on Rainier Mesa and Yucca Flat detonated in the same time period did...

Correlation or linear regression estimates of earthquake magnitude from data on historical magnitude and length of surface rupture should be based upon the correct regression. For example, the regression of magnitude on the logarithm of the length of surface rupture L can be used to estimate magnitude, but the regression of log L on magnitude cannot. Regression estimates are most...

The seismograph stations listed in this catalog were established over the period January 1964 through June 1976 in support of the Energy Research and Development Administration, Nevada (ERDA/NV) underground weapons testing program at the Nevada Test Site (NTS), central Nevada, and Amchitka, Alaska. For station listings before 1964 see Coast and Geodetic Survey publication, "Seismic Data...

Seismic wave velocities (compressional and shear) are important parameters for estimating the seismic response characteristics of various geologic units when subjected to strong earthquake ground shaking. Seismic velocities of various units often show a strong correlation with the amounts of damage following large earthquakes and have been used as a basis for certain types of seismic...

The USGS telemetered seismic system was intended primarily to record small to moderate earthquakes (magnitude 0 to 4) at distances of a few km to several hundred km. Its frequency response is such that the recorded background noise at a moderately quite Coast Range site has a relatively flat 'record' spectrum from about 1/3 Hz to about 20 Hz. With the system magnification set so that the

The United States Geological Survey (USGS), Branch of Earthquake Hazards (BEH), Las Vegas, Nevada has provided ERDA, Nevada Operations Office, with seismic monitoring support to the underground nuclear weapons test program conducted at the Nevada Test Site (NTS) since September 1961. Activities from September 15, 1961 to September 13, 1963 are summarized in the report, "Seismic Dats...

This report is a collection of stress-strain charts which were produced by deforming selected simuiated fault gouge materials. Several sets of samples consisted of intact cylinders, 1.000 inch in diameter and 2.500 inches long. The majority of the samples consisted of thin layers of the selected sample material, inserted within a diagonal sawcut in a 1.000-inch by 2.500-inch Westerly...

The epicenter of the Hollister earthquake (ML = 5.1) of November 28, 1974, is located near the center of an 81‐line trilateration network which has been surveyed annually since 1971. Five lines in the neighborhood of the epicenter were surveyed just 2 days before the earthquake, and two other lines nearby were surveyed 48 days earlier. Although some of these measurements suggest a...

Precise distance measurements of a 10×25 km 15‐station trilateration network that spans the San Andreas fault west of Palmdale, California, have been repeated annually in the period 1971–1975. The network appears to be deforming under simple uniform tensor shear of about 0.21±0.03 μstrain/yr with the direction of maximum right‐lateral shear parallel to the local strike of the San Andreas...

Measurements of ground motion generated by nuclear explosions in Nevada have been completed for 99 locations in the San Francisco Bay region, California. The recordings show marked amplitude variations in the frequency band 0.25 to 3.0 Hz that are consistently related to the local geological conditions of the recording site. The average spectral amplifications observed for vertical and...

In recent months the need has arisen to record special seismic networks consisting of a dozen or more standard NCER seismic systems telemetered to a central collection point on a reliable, portable, low-power tape recorder. Because of its simplicity and the ease with which it can be adapted for the purpose, the PI 5100 field recorder should be considered for such use. In the tests...