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B.G. Reagor

Publications and source records attributed to B.G. Reagor.

At least 37 records · Page 2Linked to original sources
USGS1986

Seismicity map of the state of Arizona

This map is one of a series of seismicity maps produced by the U. S. Geological Survey that show earthquake data of individual states or groups of states at the scale of 1:1,000,000. This map shows only those earthquakes with epicenters located within the boundaries of Arizona, even though earthquakes in nearby states or countries may have been felt or may have caused damage in Arizona. The data in table 1 were used to compile the seismicity map; these data are a corrected, expanded, and updated (through 1982) version of the data used by Algermissen (1969) for a study of seismic risk in the United States. The locations and intensities of some earthquakes were revised and intensities were assigned where none had been before. Many earthquakes were added to the original list from new data sources as well as from some old data sources that had not been previously used. The data in table 1 represent best estimates of the location of the 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 not all, especially for earthquakes that occurred before seismic instruments were universally used. Table 1 includes earthquakes reported felt in Yuma, Arizona that had no corroborating reports from other areas. These events are listed with coordinates (32.7°N., 114.6° W.) near Yuma even though it is suspected that they may have actually occurred in the Imperial Valley, California or Baja California, Mexico. Very few earthquakes have been instrumentally located near Yuma and it is believed that most historical felt reports correspond to earthquakes that occurred in the seismic zone extending from the Gulf of California northward into California. It is known that some earthquakes located graphically from phase data prior to epicenter determinations by electronic computer were erroneously located in southern Arizona and actually had locations in the Gulf of California or northern Mexico. For detailed descriptions of the effects of earthquakes in Arizona see Bulletin 193, Arizona earthquakes, 1776-1980 (reference 343) which lists the localities where the earthquakes were felt and the effects at each place. This publication also includes isoseismal maps for 41 events. The latitude and longitude coordinates of each epicenter were rounded to the nearest tenth of a degree and sorted so that all identical locations were grouped and counted. These locations are represented on the map by a triangle. The number of earthquakes at each location is shown on the map by the arabic number to the right of the triangle. The Roman numeral to the left of the triangle is the maximum Modified Mercalli intensity (Wood and Neumann, 1931) of al 1 earthquakes with epicenters at that geographic location. The absence of an intensity value indicates that no intensities have been assigned to earthquakes at that location. The year shown below each triangle is the latest year for which the maximum intensity was recorded.

Arizona↗
USGS1986

Seismicity map of the state of Utah

This map is one of a series of seismicity maps produced by the U. S. Geological Survey that show earthquake data of individual states or groups of states at the scale of 1:1,000,000. This map shows only those earthquakes with epicenters located within the boundaries of Utah, even though earthquakes in nearby states or countries may have been felt or may have caused damage in Utah. The data in table 1 were used to compile the seismicity map; these data are a corrected, expanded, and updated (through 1982) version of the data used by Algermissen (1969) for a study of seismic risk in the United States. The locations and intensities of some earthquakes were revised and intensities were assigned where none had been before. Many earthquakes were added to the original list from new data sources as well as from some old data sources that had not been previously used. The data in table 1 represent best estimates of the location of the 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 not all, especially for earthquakes that occurred before seismic instruments were universally used.

Utah↗
USGS1986

Seismicity map of the state of Idaho

This map is one of a series of seismicity maps produced by the U.S. Geological Survey that show earthquake data of individual states or groups of states at the scale of 1:1,000,000. This map shows only those earthquakes with epicenters located within the boundaries of Idaho, even though earthquakes in nearby states or countries may have been felt or may have caused damage in Idaho. The USGS and the Idaho Geological Survey are continuing to research historical data with the objective of improving the pre-instrumental data listed below. The data in table 1 were used to compile the seismicity map; these data are a corrected, expanded, and updated (through 1983) version of the data used by Algermissen (1969) for a study of seismic risk in the United States. The locations and intensities of some earthquakes were revised and intensities were assigned where none had been before. Many earthquakes were added to the original list from new data sources as well as from some old data sources that had not been previously used. The data in table 1 represent earthquake on the basis of historical and current information. Some of the aftershocks from large earthquake are listed, but not all, especially for earthquakes that occurred before seismic instruments were universally used.

Idaho↗
USGS1985

Seismicity map of the State of Wyoming

The data shown on this map and listed in table 1 are for earthquakes that were originally included in a study of seismic risk in the United States (Algermissen, 1969). This data file has been recompiled and updated through 1981. Some revisions of epicenters and intensities in the original file have been made, and intensities have been assigned to earthquakes that previously had none assigned. Only earthquakes that had epicenters within the boundary of the state are listed in table 1, even though earthquakes that had epicenters in bordering states or countries may have been felt or may have caused damage in the state. Intensity values were updated from data sources that were not available at the time or original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 represent best estimates of the 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 not all, especially for the earthquakes that occurred before seismic instruments were universally used. The data in table 1 were used to compile the seismicity map. The latitude and longitude coordinates of each epicenter were rounded to the nearest tenth of a degree. The triangles on the map represent epicenters plotted to the nearest tenth of a degree. The number of earthquakes at each location is shown on the map by the number to the right of the triangle. A Roman numeral to the left of a triangle is the maximum Modified Mercalli (MM) intensity (Wood and Neumann, 1931) of al earthquakes at that geographic location. The absence of an intensity value indicates that no intensities have been assigned to earthquakes at that location. The four-digit number shown below each triangle is the latest year for which the maximum intensity was recorded.

Wyoming↗
USGS1985

Seismicity map of the State of Montana

This map is one of a series of seismicity maps produced by the U. S. Geological Survey that show earthquake data of individual states or groups of states at the scale of 1:1,000,000. This map shows only those earthquakes with epicenters located within the boundaries of Montana, even though earthquakes in bordering states or countries may have been felt or may have caused damage in Montana. The data in table 1 were used to compile the seismicity map; these data are a corrected, expanded, and updated (through 1981) version of the data used by Algermissen (1969) for a study of seismic risk in the United States. The locations and intensities of some earthquakes were revised and intensities were assigned where none had been before. Many earthquakes were added to the original list from new data sources as well as from some old data sources that had not been previously used. No earthquakes with magnitudes greater than 2.5 were located in Montana during 1981. The data in table 1 represent best estimates of the location of the 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 not all, especially for earthquakes that occurred before seismic instruments were universally used. Special criteria used in compiling the list of earthquake in the State of Montana include the following: (1) All earthquakes with epicenters along the Montana-Wyoming border with a latitude of 45° N are listed in Montana. (2) Aftershocks of the 1925 and 1935 earthquakes were assigned the same geographic locations as the main shocks. (3) Instrumental epicenters for the 1959 Hebgen Lake earthquake and its aftershocks were 1ocated in Idaho, Montana, and Wyoming; only the ones located in Montana are included on this map. All non-instrumental locations were given the location of the main shock with an accuracy code that includes the community reporting the maximum intensity. The latitude and longitude coordinates of each epicenter were rounded to the nearest tenth of a degree and sorted so that all identical locations were grouped and counted. These locations are represented on the map by a triangle. The number of earthquakes at each location is shown on the map by the number to the right of the triangle. A Roman numeral to the left of a triangle is the maximum Modified Mercalli intensity (Wood and Neumann, 1931) of all earthquakes at that geographic location. The absence of an intensity value indicates that no intensities have been assigned to earthquakes at that location. The year shown below each triangle is the latest year for which the maximum intensity was recorded.

Montana↗
USGS1984

Seismicity map of the state of Colorado

The data shown on this map and listed in table 1 are for earthquakes that were originally included in a study of seismic risk in the United States (Algermissen, 1969). This data file has been recompiled and updated through 1981. Some revisions of epicenters and intensities in the original file have been made, and intensities have been assigned to earthquakes that previously had none assigned. Only earthquakes that had epicenters within the boundary of the state are listed in table 1, even though earthquakes that had epicenters in bordering states or countries may have been felt or may have caused damage in the state. Intensity values were updated from data sources that were not available at the time or original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 represent best estimates of the 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 not all, especially for the earthquakes that occurred before seismic instruments were universally used.

Colorado↗
USGS1983

Seismicity map of the State of Virginia

The data shown on this map and listed in table 1 are for earthquakes that were originally included in a study of seismic risk in the United States (Algermissen, 1969). This data file has been recompiled and updated through 1980. Some revisions of epicenters and intensities in the original file have been made, and intensities have been assigned to earthquakes that previouly had none assigned. Only earthquakes that had epicenters within the boundary of the State are listed in table 2, even though earthquakes that had epicenters in bordering states or countries may have been felt or may have caused damage in the State. Intensity values were updated from 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 represent best estimates of the epicenter, magnitude, and intensity of each earthquake on the basis of historical and current informaiton. Some of the aftershocks from large earthquakes are listed, but not all, especially for the earthquakes that occurred before seismic instruments were universally used.

Virginia↗
USGS1983

Seismicity map of the State of New Mexico

The data shown on this map and listed in table 1 are for earthquakes that were originally included in a study of seismic risk in the United States (Algermissen, 1969). This data file has been recompiled and updated through 1980. Some revisions of epicenters and intensities in the original file have been made, and intensities have been assigned to earthquakes that previously had none assigned. Only earthquakes that had epicenters within the boundary of the state are listed in table 1, even though earthquakes that had epicenters in bordering states or countries may have been felt or may have caused damage in the state. Intensity values were updated from data sources that were not available at the time or original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 represent best estimates of the 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 not all, especially for the earthquakes that occurred before seismic instruments were universally used.

New Mexico↗
USGS1982

Seismicity map of the state of Texas

The data shown on this map and listed in table 1 are for earthquakes that were originally included in a study of seismic risk in the United States (Algermissen, 1969). This data file has been recompiled and updated through 1981. Some revisions of epicenters and intensities in the original file have been made, and intensities have been assigned to earthquakes that previously had none assigned. Only earthquakes that had epicenters within the boundary of the state are listed in table 1, even though earthquakes that had epicenters in bordering states or countries may have been felt or may have caused damage in the state. Intensity values were updated from data sources that were not available at the time or original compilation. Some epicenters were relocated on the basis of new information. The data shown in table 1 represent best estimates of the 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 not all, especially for the earthquakes that occurred before seismic instruments were universally used.

Texas↗
USGS1981

Seismicity map of the state of Pennsylvania

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 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 ones that occurred before seismic instruments were in universal usage.

Pennsylvania↗
USGS1981

Seismicity map of the states of Delaware and Maryland

The earthquake data shown on this map and listed in tables 1 and 2 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 and 2 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.

Delaware, Maryland↗
USGS1981

Seismicity map of the State of New York

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 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 ones that occurred before seismic instruments were in universal usage. Only earthquakes located within the borders of the state of New York are listed. Many earthquakes actually located in Canada were felt in localities within New York and are listed in the literature as a New York event.

New York↗