COMMONWEALTH OF PENNSYLVANIA
Edward G. Rendell, Governor
DEPARTMENT OF CONSERVATION AND NATURAL RESOURCES
Michael DiBerardinis, Secretary
BUREAU OF TOPOGRAPHIC AND
GEOLOGIC SURVEY

Jay B. Parrish, Director

DATASET FILES

Map 69
EARTHQUAKE CATALOG AND EPICENTER MAP OF PENNSYLVANIA

compiled by
Rodger T. Faill
2004


SUMMARY

          The enclosed files present a compilation of 437 seismic events (mostly earthquakes) in and near Pennsylvania. The data include instrumentally recorded seismic events from the mid-1960s to July 31, 2003, as well as historical (pre-instrumental) events since 1724.

          The data were obtained from existing catalogs and published sources and compiled in a Microsoft Access database. Each database record encompasses just one event (main shocks, foreshocks, and aftershocks are recorded separately). Each record consists of 30 fields, which include a unique event number, map number, date, time (hour, minute, and second), location (latitude and longitude, as well as county and town), magnitude, intensity, depth of focus, source(s) of the event data, and ancillary remarks. 

           The information is presented in digital database, map, coverage, metadata, and other files, which are described below in the “Contents” section. 

OBJECTIVES
          The objectives of this study are to (1) provide a comprehensive database/catalog and coverage (dataset) of earthquake epicenters in and near Pennsylvania from 1724 to July 31, 2003, which had previously been lacking in one source; and (2) create digital files in standard formats that can be readily used by government, industry, academia, and the public to obtain geologic information critical to planning and decision making.
CONTENTS
          The links below will either open the file or the directory where the file resides on this CD–ROM (CD).  To obtain software for viewing the PDF and data files, please refer to software required for viewing the files. Please also read the disclaimer prior to using the database, map, dataset, or other information on this CD.

           The database files should be downloaded from the CD to the hard drive of your computer before use. To download, (1) make a directory on the hard drive (for example, “eqpa”); (2) select all files and directories on the CD and move them to the directory on the hard drive, keeping the directory structure of the CD intact within the new directory; and (3) select all of the downloaded files and remove the read only attribute (this is generally done through the Properties dialog box). Please note that the autoplay feature will not function after the files have been moved to the hard drive, but the links in eqpa_intro.htm (this file) will be usable.

Database/Catalog
eqpa.mdb and eqpa97.mdb—Microsoft Access database (versions 2000 and 97, respectively)
           containing an earthquake events table and a references table.
eqpadbmeta.pdf—Metadata file containing information about the format and fields of the
           Access database.
eqpa.dbf and eqparefs.dbf—Data from the earthquake events table and references table,
           respectively, of the Access database, exported in dBASE IV format.
eqpa.pdf—PDF file of the data in the earthquake events table of the Access database, in
           tabular form.
eqparefs.pdf—PDF file of the data in the references table of the Access database, in text form.

Epicenter Map/Dataset
eqpamap.pdf—PDF file of the earthquake epicenter map at 1:750,000 scale.
eqpa.tif
—Georeferenced image of the map, cropped to include only the map area and
        explanation.
eqpashp.shp—ArcGIS shapefile of the dataset for earthquake epicenters.
eqpa.e00—ArcInfo export file of the dataset for earthquake epicenters.
eqpameta.htm—Metadata file for the ArcInfo coverage.

ACKNOWLEDGMENTS

          Putting together an earthquake catalog of Pennsylvania necessarily drew upon the various existing earthquake catalogs and publications as sources of information. These sources are listed in the references table of the database. The search of historic earthquakes felt in Pennsylvania by Abdypoor and Bischke (1982) and Charles Scharnberger’s catalog of earthquakes in Pennsylvania (Scharnberger, 2003) were particularly helpful, as were the catalogs developed by the U.S. Geological Survey over the years, such as the SRA (1987) [Stover, Reagor, and Algermissen, 1987], the NCEER (1992) [Armbruster and Seeber, 1992], the CEUS (1996) [Mueller, Hopper, and Frankel, 1996], and Gordon and Dewey (1999).

          The author is indebted to Russell Wheeler of the U.S. Geological Survey and to Charles Scharnberger of Millersville University for numerous discussions on seismicity of Pennsylvania and the various available catalogs. He appreciates the thoughtful and detailed reviews that each gave to the resulting catalog and epicenter map.

          Christine Miles of the Pennsylvania Geological Survey guided and provided critical support for the assembly of the digital epicenter map of Pennsylvania and the transformation of the earthquake database into a dataset, which the author greatly appreciates. Caron O’Neil, Anne Lutz, and Christine Miles of the Pennsylvania Geological Survey thoroughly edited and corrected the database and dataset.

FURTHER INFORMATION

For more information on the contents of this CD–ROM, please contact:
Bureau of Topographic and Geologic Survey, Department of Conservation and Natural Resources, 3240 Schoolhouse Road, Middletown, PA 17057–3534; telephone 717–702–2017.

Citation of this publication should contain the following information:
Faill, R. T., compiler, 2004, Earthquake catalog and epicenter map of Pennsylvania: Pennsylvania Geological Survey, 4th ser., Map 69, CD–ROM.

Additional copies of this publication may be purchased from:
State Bookstore, Commonwealth Keystone Building, 400 North Street, Harrisburg, PA 17120–0053; telephone 717–787–5109.