| Symbol | Explanation |
|---|
| AAM | University of Michigan, Ann Arbor, USA |
| AEC | see DOE |
| AEI | see AEIC |
| AEIC | Alaska Earthquake Information Center, Fairbanks, USA |
| AGS | USGS Alaska Seismic Project, Menlo Park, California, USA |
| ALG | C.R.A.A.G., Alger-Bouzareah, Algeria |
| APT | University of Connecticut, Storrs, USA |
| ARO | Observatoire Géophysique d'Arta, Djibouti |
| ATH | National Observatory of Athens, Greece |
| AUST | Geoscience Australia, Canberra, Australia |
| BDF | Observatório Sismológico, Universidade de Brasília, Brazil |
| BER | Institutt for geovitenskap, Universitetet i Bergen, Norway |
| BGS | British Geological Survey, Edinburgh, Scotland, UK |
| BHL | Conseil National de la Recherche Scientifique, Beirut, Lebanon |
| BKN | Procurement Executive, Ministry of Defence, Blacknest, England, UK |
| BLA | Virginia Polytechnic Institute and State University, Blacksburg, USA |
| BOU | University of Colorado, Boulder, USA |
| BRK | University of California, Berkeley, USA |
| BSE | Boise State University, Boise, Idaho, USA |
| BUC | National Institute for Earth Physics, Bucharest-Magurele, Romania |
| BUT | Montana Bureau of Mines and Geology, Butte, USA |
| BYKL | GSRAS Siberian Branch, Baykal Regional Seis. Center, Irkutsk, Russia |
| CAR | Fundación Venezolana de Investigaciones Sismológicas, Caracas Venezuela |
| CASC | Central American Seismic Center, San Jose, Costa Rica |
| CERI | Center for Earthquake Research and Information, Memphis, Tennessee, USA |
| CIG | Cen. de Investigaciones Geotécnicas, San Salvador, El Salvador (closed) |
| CLE | John Carroll University, Cleveland, Ohio, USA |
| CNRM | Centre National de la Recherche Scient. et Tech., Rabat, Morocco |
| CSC | University of South Carolina, Columbia, USA |
| CSEM | Centre Sismologique Euro-Mediterranéen, Bruyères-le-Châtel, France |
| CSS | see NIC (CSS used in PDE prior to 1 Jan 2003) |
| DDA | Directorate of Disaster Affairs, Lodumlu, Ankara, Turkey |
| DHMR | National Seismological Observatory Center, Dhamar, Yemen |
| DIAS | Dublin Institute for Advanced Studies, Ireland |
| DJA | Lembaga Meteorologi dan Geofisika, Jakarta, Indonesia |
| DMN | Department of Mines and Geology, Kathmandu, Nepal |
| DNK | KMS, Geodætisk Seismisk Afdeling, Copenhagen, Denmark |
| DOE | U.S. Department of Energy (formerly AEC and ERDA), USA (explosions) |
| ECX | RESNOM, CICESE, Ensenada, Baja California, Mexico |
| ERD | see DOE |
| EXP | Explosion parameters from any group other than DOE and predecessors |
| FBB | Geologisches Landesamt Baden-Württemberg (LEDBW), Freiburg, Germany |
| FDF | IPG Observatoire Géophysique, St. Pierre, Martinique |
| GCMT | Lamont-Doherty Earth Observatory Global CMT project, New York, USA |
| GEN | Dipart. Studio del Territorio e Risorse, Università di Genova, Italy |
| GFU | Geofyzikální ústav Akademie víd Ceské republiky, Praha, Czech Rep |
| GIA | Geophysical Institute, University of Alaska, Fairbanks, USA |
| GII | Geophysical Institute of Israel, Holon, Israel |
| GLD | U.S. Geological Survey, Golden, Colorado, USA (other than NEIS) |
| GM | U.S. Geological Survey, Menlo Park, California (other than AGS) |
| GOM | Observatoire Volcanologique de Goma, Goma, Dem. Republic of the Congo |
| GRF | BGR, Zentralobservatorium Gräfenberg, Erlangen, Germany |
| GS | USGS National Earthquake Information Service, Golden, Colorado, USA |
| GUC | Departamento de Geofísica, Universidad de Chile, Santiago, Chile |
| HDC | Universidad Nacional, Campus Omar Dengo, Heredia, Costa Rica |
| HEL | Seismologian Laitos, Helsingin Yliopisto, Helsinki, Finland |
| HLW | National Research Institute of Astronomy and Geophysics, Helwan, Egypt |
| HOJ | see JSN |
| HRV | Harvard University, Cambridge, Massachusetts |
| HVO | U.S. Geological Survey, Hawaiian Volcano Observatory, Hawaii, USA |
| INDR | Inst. Nacional de Recursos Hidraulicos, Santo Domingo, Dominican Rep. |
| INEL | Idaho Nat. Engineering and Environmental Lab., Idaho Falls, Idaho, USA |
| INET | Instituto Nicaragüense de Estudios Territoriales, Managua, Nicaragua |
| INMG | Instituto de Meteorologia, Lisbon, Portugal |
| IRSA | Institutul Roman de Seismologie Aplicata, Bucharest, Romania |
| ISK | Kandilli Observatory and Earthquake Research Inst., Istanbul, Turkey |
| JER | see GII |
| JMA | Japan Meteorological Agency, Tokyo, Japan |
| JSN | Jamaica Seismograph Network, Univ. of the West Indies, Mona, Jamaica |
| KGS | Kansas Geological Survey, University of Kansas, Lawrence, USA |
| KISR | Kuwait Institute for Scientific Research, Safat, Kuwait |
| KNET | Kyrgyz Broadband Seismograph Network, La Jolla, Calif. and Kyrgyzstan |
| LAK | see KGS |
| LDG | CEA Lab. de Détection et de Géophysique, Bruyères-le-Châtel, France |
| LEDBW | see FBB |
| LIM | Instituto Geofísico del Perú, Lima, Peru |
| LIS | see INMG |
| LJU | ARSO, Urad za seizmologijo, Ljubljana, Slovenia |
| MACR | see MACRO |
| MACRO | Macroseismic location |
| MD | Duration magnitude (shown as DUR prior to 1986) |
| MDD | Instituto Geográfico y Catastral, Madrid, Spain |
| ME | Energy Magnitude |
| MEL | Seismology Research Centre, Bundoora (Melbourne), Australia |
| MERI | Maharashtra Engineering Research Institute, Nashik, Maharashtra, India |
| MG | Contributed local or regional magnitude of unspecified type |
| MPR | see RSPR |
| MRB | Institut Cartogràfic de Catalunya (ICC), Barcelona, Spain |
| MVOV | Montserrat Volcano Observatory, Mango Hill, Montserrat |
| MW | Moment Magnitude. |
| NC | Northern California Seismic Network, UC Berkeley & USGS Menlo Park, USA |
| NIC | Geological Survey Department, Nicosia, Cyprus |
| NNC | Nat. Nuclear Center, Inst. of Geophysical Research, Almaty, Kazakhstan |
| NSSC | National Syrian Seismological Center, Damascus, Syria |
| NSSP | National Survey of Seismic Protection, Yerevan, Armenia |
| OBN | Geophysical Survey, Russian Academy of Sciences, Obninsk, Russia |
| OGSO | OhioSeis Network, Ohio Geological Survey, Columbus, USA |
| OTT | Geological Survey of Canada, Ottawa, Ontario, Canada |
| PAL | Lamont-Doherty Earth Observatory, Palisades, New York, USA |
| PAS | USGS/CalTech, California Institute of Technology, Pasadena, USA |
| PDA | Instituto de Meteorologia, Obs. Afonso Chaves, Ponta Delgada, Azores |
| PDG | Seizmoloski zavod Crne Gore, Podgorica, Montenegro, Yugoslavia |
| PGC | GSC Pacific Geoscience Centre, Sidney, British Columbia, Canada |
| PIVS | Philippine Inst. of Volcanology & Seismology, Quezon City, Philippines |
| PPT | Laboratoire de Géophysique, Papeete, French Polynesia |
| PRE | Council for Geoscience, Pretoria, South Africa |
| REN | University of Nevada, Reno, USA |
| REY | Vedurstofa Islands, Reykjavik, Iceland |
| ROM | Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy |
| RSNC | Red Sísmica Nacional de Colombia, INGEOMINAS, Bogotá, Colombia |
| RSPR | Red Sísmica de Puerto Rico, Universidad de Puerto Rico, Mayagüez |
| RUVS | Rede Universitaria de Vigilancia Sismovulcanica, São Miguel, Azores |
| RYD | King Saud University, Riyadh, Saudi Arabia |
| SAN | see GUC |
| SCP | Pennsylvania State University, State College, USA |
| SDD | Universidad Autónoma de Santo Domingo, Dominican Republic |
| SEA | Geophysics Program, University of Washington, Seattle, USA |
| SEO | Korean Meteorological Administration, Seoul, South Korea |
| SFS | Real Instituto y Observatorio de la Armada, San Fernando, Spain |
| SJA | Instituto Nacional de Prevención Sísmica, San Juan, Argentina |
| SJR | see UCR |
| SKO | Seismological Observatory, Skopje University, F.Y.R. of Macedonia |
| SLC | University of Utah, Salt Lake City, USA |
| SLM | St. Louis University, St. Louis, Missouri, USA |
| SNET | Servicio Nacional de Estudios Territoriales, San Salvador, El Salvador |
| SNM | New Mexico Institute of Mining and Technology, Socorro, USA |
| SOF | Section of Seismology, Bulgarian Academy of Sciences, Sofia, Bulgaria |
| SPEC | An NEIS solution based on local model or other special methods |
| SPGM | Service de Physique du Globe, Rabat Agdal, Morocco |
| SSNC | Centro Nacional de Investigaciones Sismológicas, Santiago de Cuba, Cuba |
| STR | École et Observatoire des Sciences de la Terre, Strasbourg, France |
| SVSA | Sistema de Vigilancia Sismologica dos Acores, Ponta Delgada, Azores |
| TAP | Central Weather Bureau, Taipei, China (Taiwan) |
| TEH | Institute of Geophysics, University of Tehran, Tehran, Iran |
| TEI | see CERI |
| TEIC | see CERI |
| THE | Geophysical Laboratory, University of Thessaloniki, Greece |
| THR | Intl. Institute of Earthquake Engineering and Seismology, Tehran, Iran |
| TIR | Seismological Center, Academy of Sciences of Albania, Tirana, Albania |
| TRI | Ist. Nazle. di Oceanografia e di Geofisica Sperimentale, Trieste, Italy |
| TRN | University of the West Indies, St. Augustine, Trinidad |
| TTG | see PDG |
| TUL | Oklahoma Geological Survey, Leonard, USA |
| TVA | Tennessee Valley Authority, Knoxville, Tennessee, USA |
| UCR | Seccion de Sismología, Universidad de Costa Rica, San José, Costa Rica |
| UNM | Instituto de Geofísica, UNAM, Mexico City, DF, Mexico |
| UPA | Instituto de Geociencias, Universidad de Panamá, Panama |
| UPP | Department of Earth Sciences, Uppsala University, Uppsala, Sweden |
| USBR | U.S. Bureau of Reclamation, Denver, Colorado, USA |
| WAR | Instytutu Geofizyki, Polskiej Akademii Nauk, Warsaw, Poland |
| WEL | Institute of Geological and Nuclear Sciences, Lower Hutt, New Zealand |
| WES | Weston Observatory, Boston College, Weston, Massachusetts, USA |
| ZAG | Geophysical Institute, University of Zagreb, Croatia |
| ZUR | Schweizerischer Erdbebendienst, Zürich, Switzerland |
