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Sylvester Theodore Algermissen

Publications and source records attributed to Sylvester Theodore Algermissen.

25 records · Page 2Linked to original sources
USGS1979

Seismicity map of the State of Kentucky

The earthquake data shown on this map and listed in table 1 are a list of earthquakes that were originally used in preparing the Seismic kisk Studies in the United States (Algermissen, 1969) which have been recompiled and updated through 1977. The data have been reexamined and intensities assigned where none had been assigned before, on the basis of available data. Other intensity values were updated from new and additional data sources that were not available at the time of original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 are estimates of the most accurate epicenter, magnitude, and intensity of each earthquake, on the basis of historical and current information. Some of the aftershocks from large earthquakes are listed but are incomplete in many instances, especially for ones that occurred before seismic instruments were in universal usage.

Kentucky↗
USGS1979

Seismicity map of the State of Tennessee

The earthquake data shown on this map and listed in table 1 are a list of earthquakes that were originally used in preparing the Seismic Risk Studies in the United States (Algermissen, 1969) which have been recompiled and updated through 1977. These data have been reexamined which resulted in some revisions of epicenters and intensities as well as assignment of intensities to earthquakes that previously had none assigned. Intensity values were updated from new and additional data sources that were not available at the time of original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 are estimates of the most accurate epicenter, magnitude, and intensity of each earthquake, on the basis of historical and current information. Some of the aftershocks from large earthquakes are listed but are incomplete in many instances, especially for the ones that occurred before seismic instruments were in universal usage.

Tennessee↗
USGS1978

Development of a technique for the rapid estimation of earthquake losses

A simple, general technique has been outlined for the rapid, approximate estimation of building losses resulting from ground shaking during earthquakes. The technique has been applied to the San Francisco Bay area. Ground shaking, ground failures of various kinds, surface faulting, tsunamis, and earthquake induced fires are all responsible for earthquake building losses. Only losses associated with ground shaking are considered in this report for a number of reasons. Losses associated with various types of ground failure such as landsliding and liquefaction are difficult to estimate because the conditions necessary for these effects to occur are not completely understood and/or may be difficult to identify. Losses related to surface faulting are believed to be small as a proportion of total losses (Algermissen and others, 1972), and losses related to tsunamis have been quite rare along the central California coast. Well-established methods are available for estimating fire losses, but these losses are beyond the scope of this report.

California↗
USGS1976

A probabilistic estimate of maximum acceleration in rock in the contiguous United States

This paper presents a probabilistic estimate of the maximum ground acceleration to be expected from earthquakes occurring in the contiguous United States. It is based primarily upon the historic seismic record which ranges from very incomplete before 1930 to moderately complete after 1960. Geologic data, primarily distribution of faults, have been employed only to a minor extent, because most such data have not been interpreted yet with earthquake hazard evaluation in mind. The map provides a preliminary estimate of the relative hazard in various parts of the country. The report provides a method for evaluating the relative importance of the many parameters and assumptions in hazard analysis. The map and methods of evaluation described reflect the current state of understanding and are intended to be useful for engineering purposes in reducing the effects of earthquakes on buildings and other structures. Studies are underway on improved methods for evaluating the relativ( earthquake hazard of different regions. Comments on this paper are invited to help guide future research and revisions of the accompanying map. The earthquake hazard in the United States has been estimated in a variety of ways since the initial effort by Ulrich (see Roberts and Ulrich, 1950). In general, the earlier maps provided an estimate of the severity of ground shaking or damage but the frequency of occurrence of the shaking or damage was not given. Ulrich's map showed the distribution of expected damage in terms of no damage (zone 0), minor damage (zone 1), moderate damage (zone 2), and major damage (zone 3). The zones were not defined further and the frequency of occurrence of damage was not suggested. Richter (1959) and Algermissen (1969) estimated the ground motion in terms of maximum Modified Mercalli intensity. Richter used the terms "occasional" and "frequent" to characterize intensity IX shaking and Algermissen included recurrence curves for various parts of the country in the paper accompanying his map. The first probabilistic hazard maps covering portions of the United States were by Milne and Davenport (1969a). Recently, Wiggins, Hirshberg and Bronowicki (1974) prepared a probabilistic map of maximum particle velocity and Modified Mercalli intensity for the entire United States. The maps are based on an analysis of the historical seismicity. In general, geological data were not incorporated into the development of the maps.

Open-File Report↗