IDENTIFICATION_INFORMATION Citation: Citation_Information: Originator: National Earthquake Information Center World Data Center Publication_Date: 1994 Title: National Earthquake Information Center World Data Center for Seismology, Denver Edition: Geospatial_Data_Presentation_Form: Map Publication_Information: Publication_Place: Publisher: Other_Citation_Details: Online_Linkage: The events occurring prior to 1900 were assigned an epicenter based on the locations where damage occurred. Magnitudes are stated as Ms (Surface Wave) or the equivalent derived from intensities for pre-instrumental events. Source_Information: Source_Citation: Citation_Information: Originator: USGS/NEIC, 1973-present Publication_Date: 1973-present Title: USGS/NEIC, 1973-present Other_Citation_Details: (PDE) Catalog of earthquakes located by the USGS NEIC and its predecessors in the U.S. Coast and Geodetic Survey, the National Oceanic Survey, and the Environmental Research Laboratories of the Department of Commerce. Listings are from three different publications: (PDE-W) PDE Weekly Listing. This file covers the time period following the Monthly data up to four weeks behind the current week. The Weekly PDE data are replaced by the Monthly PDE data as soon as they become available. USGS/NEIC Most Recent Events (PDE-Q) Daily listing, known as Quick Epicenter Determinatins (QED). These data are extremely preliminary and the parameters of the earthquakes are subject to change as more data are used to relocate the earthquakes. The daily PDE-W covers the time fram following the Weekly PDE data up to the current date. These data are replaced by the Weekly PDE data. (PDE) Preliminary Determinations of Epicenters, Monthly Listing. This list is the most complete computation of hypocenters and magnitudes done by the USGS NEIC. It is normally produced a few months after the events occur. The publication is called "Preliminary" because the "final" computation of hypocenters for the world is considered to be the Bulletin of the Internation Seismological Centre (ISC), which is produced about two years after the earthquakes occur. The NEIC PDE program contributes about one-third off all data used by the ISC. Source_Information: Source_Citation: Citation_Information: Originator: USGS/NEIC Title: USGS/NEIC Most Recent Events (PDE-Q) Other_Citation_Details: This contains only PDE-Q events described in the previous section. Source_Information: Source_Citation: Citation_Information: Originator: USHIS Title: SIGNIFICANT U.S. EARTHQUAKES (USHIS) Other_Citation_Details: A catalog of principal earthquakes in the United States, 1568 - 1989 (Stover, C.W. and Coffman, J. L., 1993). The catalog is a history of earthquakes which have magnitudes greater than or equal to 4.5 or intensity of VI or larger. Exceptions are Alaska and offshore areas of California, Oregon, and Washington where only earthquakes having magnitudes of 5.5 or larger or intensitites of VI or larger are included. It does not include earthquakes in Puerto Rico. the Virgin Islands, American Samoa, Guam, or Northen Marianas. Source_Information: Source_Citation: Citation_Information: Originator: California Division of Mines and Geology Publication_Date: 1974 Title: CALIFORNIA, 1735 - 1974 (CDMG) Other_Citation_Details: compiled by Real and others (1978) and Toppozada and others (1984) at the California Division of Mines and Geology. This file includes hypocenters from catalogs of the Seismological Laboratory of the California Institute of Technology (PAS) and the Seismological Stations of the University of California at Berkeley (BRK). Source_Information: Source_Citation: Citation_Information: Originator: Earth Physics Branch (EPB) of Canada, now the Geological Survey of Canada Publication_Date: 1992 Title: CANADA, 1568 - 1992 (EPB) Other_Citation_Details: compiled by the Earth Physics Branch (EPB) of Canada, now the Geological Survey of Canada. Also includes U.S. earthquakes occurring near the Canadian border. Only the prime hypocenters (those selected by EPB/GSC as the best solutions for their earthquakes) are entered into the data base; in some cases (indicated in the authority column), these prime hypocenters may have been computed by an institution other than the EPB/GSC. Source_Information: Source_Citation: Citation_Information: Originator: INDIA Publication_Date: 1984 Title: INDIA, 1063 - 1984 (INDIA) Other_Citation_Details: This is a combination of four catalogs (Tandon. A.N. and Srivastava, H.N., 1974; Chandra, Umesh, 1977; Rao and Rao, 1984; Srivastava, H.N., and Ramachandran, 1983). See the authority column for the catalog identification. The ebtries that could be identified as duplicates from the four catalogs have been eliminated from the final listing. The abbreviations that identify the magnitude source are listed in the publication by Rao and Rao, 1984. Source_Information: Source_Citation: Citation_Information: Originator: NGDC Publication_Date: 1979 Title: MEXICO, CENTRAL AMERICA, AND CARIBBEAN, 1900 - 1979 (NGDC) Other_Citation_Details: compiled at NOAA (Rinehart and others, 1982). Source_Information: Source_Citation: Citation_Information: Originator: SISRA Publication_Date: 1981 Title: SOUTH AMERICA, 1471 - 1981 (SISRA) Other_Citation_Details: compiled for Proyecto SISRA, Programa para la Mitigacion de los Effectos de los Terremotos en la Region Andina (Projeft SISRA, Earthquake Mitigation Program in the Andean Region), edited by Askew and Algermissen, 1985. Source_Information: Source_Citation: Citation_Information: Originator: SRA Publication_Date: 1986 Title: EASTERN, CENTRAL, AND MOUNTAIN STATES OF THE UNITED STATES, 1534 - 1986 (SRA) Other_Citation_Details: (Stover and others, 1984). An early version of the catalog was developed under the direction of S.T. Algermissen for the contiguous 48 states; updated and revised files have been published in a series of Miscellaneous Field Studies Maps. The states of Nevada, California, Oregon, Washington, Alaska, and Hawaii are not covered in this catalog. SPATIAL_DATA_ORGANIZATION_INFORMATION Direct_Spatial_Reference_Method: Point Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Point Point_and_Vector_Object_Count: 5686 SPATIAL_REFERENCE_INFORMATION Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: Longitude_Resolution: Geographic_Coordinate_Units: Decimal Degrees Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1927 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: Denominator_of_Flattening_Ratio: ENTITY_AND_ATTRIBUTE_INFORMATION Detailed_Description: Entity_Type: Entity_Type_Label: sa_quakes.dbf Entity_Type_Definition: Shapefile Attribute Table Entity_Type_Definition_Source: None Attribute: Attribute_Label: Cat Attribute_Definition: Contributing source, or authority. In the following section, the abbreviation of each catalog source is in by parenthesis. The catalog abbreviations are listed in alphabetic order. Catalogs "supplied by NOAA" came to the NEIC from the National Geophysical Data Center of the National Oceanic and Atmospheric Administration (Rinehart and others, 1985). Contributing source, or authority. In the following section, the abbreviation of each catalog source is in by parenthesis. The catalog abbreviations are listed in alphabetic order. Catalogs "supplied by NOAA" came to the NEIC from the National Geophysical Data Center of the National Oceanic and Atmospheric Administration (Rinehart and others, 1985). Contributing source, or authority. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: PDE Enumerated_Domain_Value_Definition: Preliminary Determinations of Epicenters, Monthly Listing. This list is the most complete computation of hypocenters and magnitudes done by the USGS NEIC. It is normally produced a few months after the events occur. Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: PDE-Q Enumerated_Domain_Value_Definition: Daily listing, known as Quick Epicenter Determinatins (QED). These data are extremely preliminary and the parameters of the earthquakes are subject to change as more data are used to relocate the earthquakes. The daily PDE-W covers the time fram following the Weekly PDE data up to the current date. These data are replaced by the Weekly PDE data. Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: PDE-W Enumerated_Domain_Value_Definition: PDE Weekly Listing. This file covers the time period following the Monthly data up to four weeks behind the current week. The Weekly PDE data are replaced by the Monthly PDE data as soon as they become available. Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: SISRA Enumerated_Domain_Value_Definition: compiled for Proyecto SISRA, Programa para la Mitigacion de los Effectos de los Terremotos en la Region Andina (Project SISRA, Earthquake Mitigation Program in the Andean Region), edited by Askew and Algermissen, 1985. Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Year Attribute_Definition: Year earthquake occurred Attribute_Definition_Source: NEIC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 198 Range_Domain_Maximum: 1998 Attribute: Attribute_Label: Mo Attribute_Definition: Month earthquake occurred Attribute_Definition_Source: NEIC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 12 Attribute: Attribute_Label: Da Attribute_Definition: Day earthquake occurred Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Range Domain (1-31) Attribute: Attribute_Label: Orig_time Attribute_Definition: (Orig Time in Screen Format) Given in Coordinated Universal Time (UTC) Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Number Field - Time written in coordinated universal time (UTC) Attribute: Attribute_Label: Lat Attribute_Definition: Latitude Attribute_Definition_Source: NEIC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -60 Range_Domain_Maximum: 25.9 Attribute: Attribute_Label: Lon Attribute_Definition: Longitude Attribute_Definition_Source: NEIC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -94.49 Range_Domain_Maximum: -32.56 Attribute: Attribute_Label: Dep Attribute_Definition: Depth: Value given in kilometers Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Range Domain - depth in km Attribute: Attribute_Label: Mag Attribute_Definition: Magnitude, a logarithmic measure of the "size" of an earthquake, is related to the energy released as seismic waves at the focus of an earthquake. Although the magnitude scale has neither "top" nor "bottom" values, the highest magnitude known was about 9.5, the lowest about -3.0. On this logarithmic scale, a magnitude 6.0 shallow-focus earthquake represents elastic-wave energy about 30 times larger than that generated by a magnitude 5.0 earthquake, 900 times (30x30) larger than that of a magnitude 4.0 shock. Many factors influence the determination of earthquake magnitude, including focal depth, distance between earthquake focus and observing station, frequency content of the sampled energy, and earthquake radiation pattern. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 5 Range_Domain_Maximum: 9.5 Attribute: Attribute_Label: Maginfo Attribute_Definition: The contributed magnitude field consists of 7 characters: positions 1-2 = magnitude scale; and postions 3-7 = organization source; if blank, the source is the same as the one shown under the catalog source column. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Broken into Mag scale and Mag org Attribute: Attribute_Label: Iefm Attribute_Definition: Information: Dots are used in place of blanks to aid in the distinction between the columns Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Broken into Intensity, EFF, FPS, and MO Attribute: Attribute_Label: Dtsvnwg Attribute_Definition: Information: Dots are used in place of blanks to aid in the distinction between the columns Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Broken into Diastroph., Tsunami, Seiche, Volcanism, NonTect, Waves, and Misc. Attribute: Attribute_Label: Dist Attribute_Definition: Radial distance: On radius searches, the distance in kilometers between designated input point and earthquake location. The distance value is truncated to the whole kilometer. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Attribute: Attribute_Label: Intensity Attribute_Definition: Maximum intensity on the Modified Mercalli Intensity Scale of 1931 (Wood and Neumann, 1931) or any similar 12-point intensity scale. It may also be an MMI value approximated from other intensity scales such as Ross-Forel or Japan Meteorological Agency. Possible intensity values are 1 - 9; X = 10; E = 11; T = 12. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Range domain: 1 - 9; X = 10; E = 11; T = 12. Attribute: Attribute_Label: EFF Attribute_Definition: Cultural Effects: The most severe effect is listed (C = Casualities; D = Damage; F = Felt; H = Heard). Note that casualties includes human deaths or injuries. Domestic animal casualties are considered to be damage. Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: A Enumerated_Domain_Value_Definition: may mean H - heard Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: C Enumerated_Domain_Value_Definition: casualties Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: D Enumerated_Domain_Value_Definition: damage Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: F Enumerated_Domain_Value_Definition: felt Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: FPS Attribute_Definition: Fault Plane Solution: Coded as an "F" to indicate the availability of a fault plane solution in the publication, "Preliminary Determination of Epicenters, Monthly Listing". Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: F Enumerated_Domain_Value_Definition: Coded as an "F" to indicate the availability of a fault plane solution in the publication, "Preliminary Determination of Epicenters, Monthly Listing". Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Moment Attribute_Definition: Moment Tension Solution: Coded as an "G" to indicate the availability of a moment tensor solution in the publication "Preliminary Determination of Epicenters, Monthly Listing" (Sipkin, 1982; Dziewonski, 1980; and Hanks and others, 1979). Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: 2 Enumerated_Domain_Value_Definition: unknown Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: 3 Enumerated_Domain_Value_Definition: unknown Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: 6 Enumerated_Domain_Value_Definition: unknown Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: 7 Enumerated_Domain_Value_Definition: unknown Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: G Enumerated_Domain_Value_Definition: Coded as an "G" to indicate the availability of a moment tensor solution in the publication "Preliminary Determination of Epicenters, Monthly Listing" (Sipkin, 1982; Dziewonski, 1980; and Hanks and others, 1979). Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: X Enumerated_Domain_Value_Definition: International Data Exchange: An "X" in this column identifies the event as a "IDE" earthquake Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Diastroph Attribute_Definition: Diastrophism Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: 7 Enumerated_Domain_Value_Definition: Uplift or Subsidence Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: 8 Enumerated_Domain_Value_Definition: Faulting and Uplift or Subsidence Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: F Enumerated_Domain_Value_Definition: Faulting Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: S Enumerated_Domain_Value_Definition: Subsidence Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: U Enumerated_Domain_Value_Definition: Uplift Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Tsunami Attribute_Definition: Tsunami Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: Q Enumerated_Domain_Value_Definition: Questionable tsunami Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: T Enumerated_Domain_Value_Definition: Tsunami generated Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Seiche Attribute_Definition: Seiche Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: S Enumerated_Domain_Value_Definition: Seiche Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Volcanism Attribute_Definition: Volcanism Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: V Enumerated_Domain_Value_Definition: Earthquake associated with volcanism Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: NonTect Attribute_Definition: Non-Tectonic Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: E Enumerated_Domain_Value_Definition: Explosion Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: I Enumerated_Domain_Value_Definition: Collapse Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Waves Attribute_Definition: Guided Waves in Atmospheric And/Or Ocean Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: A Enumerated_Domain_Value_Definition: Acoustic wave Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Misc Attribute_Definition: Miscellaneous Phenomena Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: . Enumerated_Domain_Value_Definition: none Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: L Enumerated_Domain_Value_Definition: Liquefaction Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: M Enumerated_Domain_Value_Definition: More than one of these phenomena observed. Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: S Enumerated_Domain_Value_Definition: Landslides and/or Avalanches Enumerated_Domain_Value_Definition_Source: NEIC Enumerated_Domain_Value: V Enumerated_Domain_Value_Definition: Lights or other visual phenomena seen Enumerated_Domain_Value_Definition_Source: NEIC Attribute: Attribute_Label: Mag_scale Attribute_Definition: Magnitude Scale Attribute_Definition_Source: NEIC Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 0 Enumerated_Domain_Value_Definition: unknown Enumerated_Domain_Value_Definition_Source: none Enumerated_Domain_Value: mb Enumerated_Domain_Value_Definition: Body-wave (mb): Magnitude values are computed based on the seismic-wave period greater than or equal to 0.1 and less than or equal to 3.0, and distance is greater than or equal to 5 degrees. Enumerated_Domain_Value_Definition_Source: Gutenberg and Richter, 1956 Enumerated_Domain_Value: MD Enumerated_Domain_Value_Definition: Duration Magnitudes (MD): These estimates are derived from the duration or coda length of earthquake vibrations. Duration or coda length magnitude scales are normally adjusted to agree with ML or Mn estimates. The MD formulas vary for different geographic regions and for different seismographic instruments. Enumerated_Domain_Value_Definition_Source: Coda-length magnitude Enumerated_Domain_Value: ME Enumerated_Domain_Value_Definition: Energy Magnitude (Me): These magnitudes are computed from the radiated energy using the method described in Choy and Boatwright (1995). The energy radiated by an earthquake is estimated from the energy spectral density of the broadband P waves (Boatwright and Choy, 1986). The Me can complement moment magnitudes (Mw) in describing the size of an earthquake. Me, being derived from velocity power spectra, is a measure of the amount of damage that could be caused. Mw, being derived from low-frequency asymptote of displacement spectra, is more physically related to the final static displacement of an earthquake. Enumerated_Domain_Value_Definition_Source: Boatwright and Choy, 1986 Enumerated_Domain_Value: MI Enumerated_Domain_Value_Definition: Felt Area Magnitudes (FA or MI): The estimate is compatible with an estimated mb magnitude. It is commonly computed from the felt area for earthquakes which occurred before seismic instruments were in general use. The estimates are based on isoseismal maps or defined areas using intensity-attenuation relationships. Enumerated_Domain_Value_Definition_Source: Magnitude computed from the epicentral intensity value Enumerated_Domain_Value: ML Enumerated_Domain_Value_Definition: Local Magnitude (ML): This magnitude is generally referred to as the true "Richter magnitude" (originally defined for California). The values are computed for distances less than 600 km with depths less than 70 km. These estimates are computed in the western part of the United States as well as world-wide, often using different calibrating functions. Enumerated_Domain_Value_Definition_Source: Richter, 1958 Enumerated_Domain_Value: Ms Enumerated_Domain_Value_Definition: Surface-wave (Ms): Magnitudes are computed for earthquakes that are located at distances between 20 and 160 geocentric degrees from the recording station, seismic-wave period between 18 and 22 seconds, and depth is less than 50 km (generally Ms magnitudes are not computed for depths greater than 50 km. Enumerated_Domain_Value_Definition_Source: Bath, 1966 Enumerated_Domain_Value: Mw Enumerated_Domain_Value_Definition: Moment Magnitude (Mw): The magnitude is computed from a long-period body- and mantle-wave moment tensor inversion method; it is also related to the product of the area of the earthquake fault, multiplied by the average fault slip over that area and by the shear modulus of the fault rocks. The Mw value is approximately the same as the Ms magnitude value. Enumerated_Domain_Value_Definition_Source: Hanks and Kanamori, 1979 Enumerated_Domain_Value: SI Enumerated_Domain_Value_Definition: Unknown Enumerated_Domain_Value_Definition_Source: none Attribute: Attribute_Label: Org_source Attribute_Definition: Organization Source Attribute_Definition_Source: NEIC Attribute_Domain_Values: Unrepresentable_Domain: Character Field Overview_Description: Entity_and_Attribute_Overview: Entity_and_Attribute_Detail_Citation: Catalog Source CATALOG SOURCE: (CAT in Screen Format) Contributing source, or authority. In the following section, the abbreviation of each catalog source is in by parenthesis. The catalog abbreviations are listed in alphabetic order. Catalogs "supplied by NOAA" came to the NEIC from the National Geophysical Data Center of the National Oceanic and Atmospheric Administration (Rinehart and others, 1985). NOTE: Hypocenters and magnitudes of some earthquakes may differ from catalog to catalog depending on the earthquake catalog from which the information is taken. SIGNIFICANT WORLDWIDE EARTHQUAKES (NOAA): This catalog is a listing of earthquakes, 2150 B.C. - 1991 (Paula K. Dunbar, Patricia A. Lockridge, and Lowell S. Whiteside, September 1992) supplemented by post-1991 data from the USGS/NEIC. The list includes all events that meet at least one of the following criteria: 1. Moderate damage (approximately $1 million or more) 2. Ten or more deaths 3. Magnitude 7.5 or greater 4. Intensity X or greaterbr> The events occurring prior to 1900 were assigned an epicenter based on the locations where damage occurred. Magnitudes are stated as Ms (Surface Wave) or the equivalent derived from intensities for pre-instrumental events. The explanation of the codes is listed under the AUTHORITY column. USGS/NEIC, 1973-PRESENT: (PDE) Catalog of earthquakes located by the USGS NEIC and its predecessors in the U.S. Coast and Geodetic Survey, the National Oceanic Survey, and the Environmental Research Laboratories of the Department of Commerce. Listings are from three different publications: (PDE-W) PDE Weekly Listing. This file covers the time period following the Monthly data up to four weeks behind the current week. The Weekly PDE data are replaced by the Monthly PDE data as soon as they become available. USGS/NEIC Most Recent Events (PDE-Q) Daily listing, known as Quick Epicenter Determinatins (QED). These data are extremely preliminary and the parameters of the earthquakes are subject to change as more data are used to relocate the earthquakes. The daily PDE-W covers the time fram following the Weekly PDE data up to the current date. These data are replaced by the Weekly PDE data. (PDE) Preliminary Determinations of Epicenters, Monthly Listing. This list is the most complete computation of hypocenters and magnitudes done by the USGS NEIC. It is normally produced a few months after the events occur. The publication is called "Preliminary" because the "final" computation of hypocenters for the world is considered to be the Bulletin of the Internation Seismological Centre (ISC), which is produced about two years after the earthquakes occur. The NEIC PDE program contributes about one-third off all data used by the ISC. USGS/NEIC Most Recent Events (PDE-Q): This contains only PDE-Q events described in the previous section. SIGNIFICANT U.S. EARTHQUAKES (USHIS): A catalog of principal earthquakes in the United States, 1568 - 1989 (Stover, C.W. and Coffman, J. L., 1993). The catalog is a history of earthquakes which have magnitudes greater than or equal to 4.5 or intensity of VI or larger. Exceptions are Alaska and offshore areas of California, Oregon, and Washington where only earthquakes having magnitudes of 5.5 or larger or intensitites of VI or larger are included. It does not include earthquakes in Puerto Rico. the Virgin Islands, American Samoa, Guam, or Northen Marianas. CALIFORNIA, 1735 - 1974 (CDMG): compiled by Real and others (1978) and Toppozada and others (1984) at the California Division of Mines and Geology. This file includes hypocenters from catalogs of the Seismological Laboratory of the California Institute of Technology (PAS) and the Seismological Stations of the University of California at Berkeley (BRK). CANADA, 1568 - 1992 (EPB): compiled by the Earth Physics Branch (EPB) of Canada, now the Geological Survey of Canada. Also includes U.S. earthquakes occurring near the Canadian border. Only the prime hypocenters (those selected by EPB/GSC as the best solutions for their earthquakes) are entered into the data base; in some cases (indicated in the authority column), these prime hypocenters may have been computed by an institution other than the EPB/GSC. INDIA, 1063 - 1984 (INDIA): This is a combination of four catalogs (Tandon. A.N. and Srivastava, H.N., 1974; Chandra, Umesh, 1977; Rao and Rao, 1984; Srivastava, H.N., and Ramachandran, 1983). See the authority column for the catalog identification. The ebtries that could be identified as duplicates from the four catalogs have been eliminated from the final listing. The abbreviations that identify the magnitude source are listed in the publication by Rao and Rao, 1984. MEXICO, CENTRAL AMERICA, AND CARIBBEAN, 1900 - 1979 (NGDC): compiled at NOAA (Rinehart and others, 1982). SOUTH AMERICA, 1471 - 1981 (SISRA): compiled for Proyecto SISRA, Programa para la Mitigacion de los Effectos de los Terremotos en la Region Andina (Projeft SISRA, Earthquake Mitigation Program in the Andean Region), edited by Askew and Algermissen, 1985. EASTERN, CENTRAL, AND MOUNTAIN STATES OF THE UNITED STATES, 1534 - 1986 (SRA): (Stover and others, 1984). An early version of the catalog was developed under the direction of S.T. Algermissen for the contiguous 48 states; updated and revised files have been published in a series of Miscellaneous Field Studies Maps. The states of Nevada, California, Oregon, Washington, Alaska, and Hawaii are not covered in this catalog. Date DATE: Year,Month,Day - Year is preceded by a "-" to indicate B.C. date. Origin Time and Authority ORIGIN TIME: (Orig Time in Screen Format) Given in Coordinated Universal Time (UTC) AUTHORITY: The symbol follows the origin time and refers to the organization that supplied the origin time/coordinate parameters. Coordinates Use decimal degrees. LAT: Geographic Latitude. Negative value = South. LONG: Geographic Longitude. Negative value = West. Depth DEPTH: Value given in kilometers. DEPTH CONTROL: (Dep on Screen Format) A = Assigned. D = Depth restrained based on 2 or more compatible pP phases and/or unidentified secondary arrivals used as pP. N = Restrained to normal depth (33 km). G = Restrained by geophysicist. S = Depth control aided by S-phase data. % = Questionable value (SSR catalog). * = Less reliable depth estimate. Accuracy of depth lies between 8.5 km and 16 km based on 90% confidence ellipse. ? = Poor depth estimate; depth accuracy is estimated to be greater than 16 km based on 90% confidence ellipse. Blank = Good depth estimate and depth unrestrained in contributed hypocenters from other networks. Depth accuracy is estimated to be less than 8.5 km based on 90% confidence ellipse. MAGNITUDES MAGNITUDES: Magnitude, a logarithmic measure of the "size" of an earthquake, is related to the energy released as seismic waves at the focus of an earthquake. Although the magnitude scale has neither "top" nor "bottom" values, the highest magnitude known was about 9.5, the lowest about -3.0. On this logarithmic scale, a magnitude 6.0 shallow-focus earthquake represents elastic-wave energy about 30 times larger than that generated by a magnitude 5.0 earthquake, 900 times (30x30) larger than that of a magnitude 4.0 shock. Many factors influence the determination of earthquake magnitude, including focal depth, distance between earthquake focus and observing station, frequency content of the sampled energy, and earthquake radiation pattern. Magnitude values calculated by the USGS with a brief description of parameters are shown below (see paragraphs under Contributed Magnitudes for appropriate references): Surface-wave (Ms): Magnitudes are computed for earthquakes that are located at distances between 20 and 160 geocentric degrees from the recording station, seismic-wave period between 18 and 22 seconds, and depth is less than 50 km (generally Ms magnitudes are not computed for depths greater than 50 km. Body-wave (mb): Magnitude values are computed based on the seismic-wave period greater than or equal to 0.1 and less than or equal to 3.0, and distance is greater than or equal to 5 degrees. Moment Magnitude (Mw): The magnitude is computed from a long-period body- and mantle-wave moment tensor inversion method; it is also related to the product of the area of the earthquake fault, multiplied by the average fault slip over that area and by the shear modulus of the fault rocks. The Mw value is approximately the same as the Ms magnitude value. Energy Magnitude (Me): These magnitudes are computed from the radiated energy using the method described in Choy and Boatwright (1995). The energy radiated by an earthquake is estimated from the energy spectral density of the broadband P waves (Boatwright and Choy, 1986). The Me can complement moment magnitudes (Mw) in describing the size of an earthquake. Me, being derived from velocity power spectra, is a measure of the amount of damage that could be caused. Mw, being derived from low-frequency asymptote of displacement spectra, is more physically related to the final static displacement of an earthquake. Local Magnitudes: Local Magnitude (ML): This magnitude is generally referred to as the true "Richter magnitude" (originally defined for California). The values are computed for distances less than 600 km with depths less than 70 km. These estimates are computed in the western part of the United States as well as world-wide, often using different calibrating functions. Local or Regional Magnitude (Mn or MbLg): This value is calculated for the area of North America east of the Rocky Mountains. It is computed from the vertical component 1-second Lg seismic-waves (short-period surface waves). It has also been used in other parts of the world, using different calibrating functions. Other Magnitudes: Duration Magnitudes (MD): These estimates are derived from the duration or coda length of earthquake vibrations. Duration or coda length magnitude scales are normally adjusted to agree with ML or Mn estimates. The MD formulas vary for different geographic regions and for different seismographic instruments. Felt Area Magnitudes (FA or MI): The estimate is compatible with an estimated mb magnitude. It is commonly computed from the felt area for earthquakes which occurred before seismic instruments were in general use. The estimates are based on isoseismal maps or defined areas using intensity-attenuation relationships. Unknown Magnitudes (UK): The computational method was unknown and could not be determined from published sources. The magnitude section of the earthquake line consists of two parts: magnitude values (mb and MS) determined by the National Earthquake Information Service (NEIS); and Contributed Magnitude values provided by other organizations (including NEIS). The headings have the following meanings: mb = Average NEIS body-wave magnitude. OBS = Number of amplitudes used in the mb magnitude computation. Ms = Average NEIS surface-wave magnitude (if given, Z = vertical component, H = horizonatal component). OBS = Number of amplitudes used in the surface-wave magnitude computation. CONTRIBUTED VALUES: Any magnitude other than NEIS mb and Ms may show in these fields, including some magnitudes computed at NEIS. The value may have been calculated from one station or it may be an average magnitude value from a number of stations in the network. Up to two magnitudes may be given here. The second magnitude (if given) is coded on a line immediately beneath the first one. The contributed magnitude field consists of 11 characters: positions 1-4 = magnitude value; positions 5-6 = magnitude scale; and postions 7-11 = organization source; if blank, the source is the same as the one shown under the catalog source column. A number of magnitude scales are defined by source agencies or institutions. The magnitude scales in the data base include: UK = Unknown magnitude scale Ms = Surface-wave magnitude; Bath, 1966 mb = Body-wave magnitude; Gutenberg and Richter, 1956 ML = Local magnitude; Richter, 1958 Mn = Nuttli magnitude; Nuttli, 1973 MD = Coda-length magnitude FA or MI = Felt area magnitude; approximately equivalent to an mb value mB = Broad-band, body-wave magnitude; Abe (1981, 1982, 1984), Abe and Kanamori, 1979, and Abe and Noguchi (1983a,b) Mw = Moment magnitude, Hanks and Kanamori, 1979 Mz = Magnitude based on the cycles/second of the Sg-phase MI = Magnitude computed from the epicentral intensity value K = Energy class magnitude value; Kondorskaya and others, 1982. INFORMATION INFORMATION (IEFM DTSVNWG on Screen Search): Dots are used in place of blanks to aid in the distinction between the columns. Read the sub-headers vertically. Intensity (sub-header INT): Maximum intensity on the Modified Mercalli Intensity Scale of 1931 (Wood and Neumann, 1931) or any similar 12-point intensity scale. It may also be an MMI value approximated from other intensity scales such as Ross-Forel or Japan Meteorological Agency. Possible intensity values are 1 - 9; X = 10; E = 11; T = 12. Cultural Effects (sub-header EFF): The most severe effect is listed (C = Casualities; D = Damage; F = Felt; H = Heard). Note that casualties includes human deaths or injuries. Domestic animal casualties are considered to be damage. Isoseismal Map (sub-header MAP): (Expanded Format only) Indicates the publication where an isoseismal map for this event has been published. U = United States Earthquakes. E = Earthquake Notes. (Now Seismological Research Letters) P = Preliminary Determination of Epicenters. W = Wellington (New Zealand Seismology Reports, Wellington, N.Z.). N = Nature Magazine. S = Bulletin of the Seismological Society of America. Fault Plane Solution (sub-header FPS): Coded as an "F" to indicate the availability of a fault plane solution in the publication, "Preliminary Determination of Epicenters, Monthly Listing". Moment Tensor Solution (sub-header MO): Coded as an "G" to indicate the availability of a moment tensor solution in the publication "Preliminary Determination of Epicenters, Monthly Listing" (Sipkin, 1982; Dziewonski, 1980; and Hanks and others, 1979). ISC Alternate Depth Indicator (sub-header DEP): A "D" in this column indicates that a pP depth is given, but the pP depth is not the adopted depth in the hypocenter solution. International Data Exchange (sub-header IDE): An "X" in this column identifies the event as a "IDE" earthquake. Preferred Solution (sub-header PFD): A "P" in this column designates a preferred solution. Earthquake hypocenters which are located within a seismic network, such as Pasadena or Berkeley, or seismic catalogs which have undergone critical review during their compilation will be designated as a preferred solution. Flag (sub-header FLG): Currently not used. PHENOMENA Diastrophism: (sub-header D) F = Faulting. U = Uplift. S = Subsidence. 3 = Uplift and Subsidence. 4 = Uplift and Faulting. 5 = Faulting and Subsidence. 6 = Faulting with Uplift and Subsidence. 7 = Uplift or Subsidence. 8 = Faulting and Uplift or Subsidence. Tsunami: (sub-header T) T = Tsunami generated. Q = Questionable Tsunami. Seiche: (sub-header S) S = Seiche. Q = Questionable Seiche. Volcanism: (sub-header V) V = Earthquake associated with volcanism. Non-Tectonic: (sub-header N) E = Explosion. I = Collapse. C = Coal bump or Rockburst in a coal mine. R = Rockburst. M = Meteoritic. N = Either known to be or likely to be of non-tectonic origin. ? = Classified as an earthquake, but a non-tectonic origin cannot be ruled out. V = Reservoir induced earthquake. Guided Waves in Atmospheric And/Or Ocean: (sub-header W) T = T-wave. A = Acoustic wave. G = Gravity wave. B = Both A and G. M = T-wave plus and A or G. Miscellaneous Phenomena: (sub-header G) L = Liquefaction. G = Geyser. S = Landslides and/or Avalanches. B = Sandblows. C = Ground cracks not known to be an expression of faulting. V = Lights or other visual phenomena seen. O = Olfactory (Unusual odors noted). M = More than one of these phenomena observed. Radial Distance RADIAL DISTANCE: On radius searches, the distance in kilometers between designated input point and earthquake location. The distance value is truncated to the whole kilometer. DISTRIBUTION_INFORMATION Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: National Earthquake Information Center; World Data Center Contact_Person: Madeleine Zirbes Contact_Position: Contact_Address: Address_Type: mailing and physical address Address: City: State_or_Province: Postal_Code: Country: Contact_Voice_Telephone: Contact_Facsimile_Telephone: Contact_Electronic_Mail_Address: zirbes@usgs.gov Hours_of_Service: Resource_Description: Distribution_Liability: METADATA_REFERENCE_INFORMATION Metadata_Date: 20000825 Metadata_Review_Date: Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Contact_Person: Contact_Position: Contact_Address: Address_Type: Mailing and physical address Address: City: State_or_Province: Postal_Code: Country: Contact_Voice_Telephone: Contact_Facsimile_Telephone: Contact_Electronic_Mail_Address: Hours_of_Service: Metadata_Standard_Name: FGDC CSDGM Metadata_Standard_Version: FGDC-STD-001-1998