QUICK REFERENCE

 

EARTHQUAKES

 

 

Earthquakes:        Identification Information

Originator:  National Earthquake Information Center World Data Center

                                Date:  2003

                                Title:  National Earthquake Information Center World Data Center for Seismology,

Denver

                                Purpose:  unknown

                                Abstract:  USGS/NEIC, 1973- March 2003:

  (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.

 

  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.

 

                                Access Constraints:  none 

                                Use Constraints:  It is ultimately the user's responsibility to assess the accuracy and completeness of a data-set extracted

from the data base and to determine if these are sufficient for the purposes to which the data-set would be applied.

 

            Ordering Instructions:  full dataset available online, see online linkage below

 

                                Contact Person:  Madeleine Zirbes

                                Contact Organization:  U.S. Geological Survey; National Earthquake Information Center

                                City:  Denver

                                State or Province: Colorado

                                Postal Code:

                                Country:  USA

 

Online Linkage: http://wwwneic.cr.usgs.gov/neis/epic/database.html

 

                                Entity and Attribute Information (table heading explanations)

                                Shape:  ArcView file type (quakes_pde1973_mar2003.shp, quakes_significant_noaa .shp)

                                Source:  Contributing source, or authority: 

                                                PDE:  Preliminary Determinations of Epicenters, Monthly Listing

                                Year:  Year earthquake occurred

                                Mo: Month earthquake occurred

                                Da: Day earthquake occurred

                                Orig_time:  (Orig Time in Screen Format) Given in Coordinated Universal Time (UTC)

                                Lat: Latitude

                                Lon: Longitude

                                Dep: Depth: value given in kilometers

                                Mag: 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.

                                 

Global GIS Note: Although the Global GIS interface shows earthquakes above magnitude 4, lower magnitudes exist in the file. To change the legend, please see the Arc View tutorial in the help section or use the Earthquake Tools in the interface to change legends. This will allow one to draw all earthquakes in this database.