John A. Power Paul A. Friberg Mathew M. Haney Thomas Parker Scott D. Stihler James P. Dixon 201905 Digital Scientific Investigations Report SIR 2019-5037 Reston, VA U.S. Geological Survey https://doi.org/10.3133/sir20195037 The Alaska Volcano Observatory (AVO) has maintained an earthquake catalog since 1989 that now contains over 120,000 hypocenters and magnitudes that occurred near Alaskan volcanoes. Since 1989 the seismic instrumentation and data acquisition and processing techniques have undergone numerous changes as computer systems and seismic processing software have advanced and evolved. In this report we recalculate earthquake hypocenters and magnitudes in a consistent manner between October 1989 and January 2018. The new hypocenters and magnitudes are archived at the AVO within an Advanced National Seismic Quake Monitoring System (AQMS) database and in the compressed UNIX tar file that accompanies this publication. Volcano monitoring 19891013 present publication date Complete None planned -179.99999 -140.0 63.074865689106 50.736455135518 USGS Thesaurus Seismic Networking GNIS Aleutian Volcanic Arc none none John A Power ALASKA REGION: VOLCANO SCIENCE CENTER Research Geophysicist mailing and physical

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Anchorage AK 99508 United States 907-786-7426 jpower@usgs.gov No formal attribute accuracy tests were conducted No formal logical accuracy tests were conducted Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. No formal positional accuracy tests were conducted No formal positional accuracy tests were conducted Hypocenter errors were calculated using the USGS program Hypoinverse 201812 1.0E-4 1.0E-4 Degrees, minutes, and decimal seconds wgs84 WGS84 sea level 0.01 km Explicit depth coordinate included with horizontal coordinates Earthquake catalog Earthquake hypocenter and magnitude data Klein, F.W., 2002, User’s guide to HYPOINVERSE–2000, a Fortran program to solve for earthquake locations and magnitudes: U.S. Geological Survey Open-File Report 02–171, 123 p., https://doi.org/10.3133/ofr02171. Earthquake Hypocenters and Magnitudes Earthquake Hypocenters and magnitudes Klein, F.W., 2002, User’s guide to HYPOINVERSE–2000, a Fortran program to solve for earthquake locations and magnitudes: U.S. Geological Survey Open-File Report 02–171, 123 p., https://doi.org/10.3133/ofr02171. Earthquake Hypocenters and magnitudes Earthquake Hypocenters and magnitudes Klein, F.W., 2002, User’s guide to HYPOINVERSE–2000, a Fortran program to solve for earthquake locations and magnitudes: U.S. Geological Survey Open-File Report 02–171, 123 p., https://doi.org/10.3133/ofr02171. John A Power ALASKA REGION: VOLCANO SCIENCE CENTER Research Geophysicist mailing and physical

4230 University Drive

Anchorage AK 99508 United States 907-786-7426 jpower@usgs.gov NA This UNIX tar file contains earthquake hypocenter data. The user must have software capable of uncompressing a UNIX tar file. 20190510 John Power USGS - Alaska Volcano Observatory Geophysicist mailing and physical

4230 University Drive

Anchorage AK 99508 USA 907-786-7426 jpower@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998