To facilitate the use of the enormous amount of earthquake data presently available, Pacific Northwest Laboratory (PNL) formed an extensive data base of compiled seismic data. PNL also developed many useful and unique computer techniques for analysis and display of the data. These techniques could be used in many areas of the United States to support nuclear waste management and other energy-related activities. Software associated with the data base includes programs for editing earthquake files; sorting files with respect to time, location, or magnitude; selecting data by use of various parameters; and merging files. These techniques allow the rapid formation of data files that are tailored to specific interests. The desired file may then be listed or displayed graphically by means of PNL's diversified graphic capability. From the data analysis software, an accurate and comprehensive earthquake catalog for the Pacific Northwest was created. This catalog was produced by merging data from many sources and includes microearthquake data. Duplicate events were eliminated, while all information available for a particular event was retained. Graphic displays can plot two- and three-dimensional epicenter or hypocenter information. Magnitude and/or depth information can be represented on two-dimensional plots by using color or symbol size. Plots canmore » be produced using a variety of map projections and at a specified scale. This capability allows the use of any desired map as a base map for the display of earthquake data. Additional information such as rivers, coastlines, faults, and boundaries may also be included on the plots. Data may also be displayed using normal or two-dimensional histograms. 19 figures, 7 tables.« less