# Network Code	Network Name	Network Operator	Network Country (ISO & Name)	Network Website	Deployment Country (if different)	Digital Object Identifier (DOI)
O1	The NWMO Seismic Network	Nanometrics Seismological Instruments	Canada		Canada	
O2	Oklahoma Consolidated Temporary Seismic Networks	Oklahoma Geological Survey	United States of America	http://www.ou.edu/content/ogs/research/earthquakes/seismicstations.html	United States of America	10.7914/SN/O2
OA	AusArray Transportable Array	Geoscience Australia	Australia		Australia	
OB	"Osservatorio Sismico ""A. Bina"""	"Osservatorio Sismico ""A. Bina"", Perugia"	Italy		Italy	
OC	Observatorio Sismológico CIGEOBIO CONICET	CONICET	Argentina	http://sismo.conicet.gov.ar	Argentina	
OE	Austrian Seismic Network	ZAMG - Zentralanstalt für Meterologie und Geodynamik	Austria	https://www.zamg.ac.at/cms/en/geophysics/seismic-network-of-austria	Austria	10.7914/SN/OE
OF	European Multidisciplinary Seafloor and Water Column Observatory - France	CNRS	France		France	
OG	Sismalp	Observatoire de Grenoble, Grenoble	France		France	
OH	Ohio Seismic Network	Ohio Geological Survey	United States of America	http://geosurvey.ohiodnr.gov/earthquakes-ohioseis/ohioseis-home	Ohio	10.7914/SN/OH
OI	Oceania International	USGS			Oceania	10.7914/2jer-f064
OK	Oklahoma Seismic Network	Oklahoma Geological Survey	United States of America	http://www.ou.edu/content/ogs/research/earthquakes/seismicstations.html	United States of America	10.7914/SN/OK
OL	Cornegliano Laudense Seismic Network	Istituto Nazionale di Oceanografia e di Geofisica Sperimentale	Italy		Italy	10.7914/SN/OL
OM	Earthquake Monitoring Program of Oman	Sultan Qaboos University	Oman	http://www.squ.edu.om/emc	Oman	
ON	Rede Sismográfica do Sul e do Sudeste	Observatório Nacional, Rio de Janeiro, RJ	Brazil	http://www.rsis1.on.br/	Brazil	10.7914/SN/ON
OO	Ocean Observatories Initiative	Rutgers University	United States of America	http://www.oceanobservatories.org/	Juan de Fuca Plate	10.7914/SN/OO
OQ	Oklahoma Structural and Site Effects Network	Oklahoma State University	United States of America		United States of America	10.7914/SN/OQ
OR	OR - Reykjavik Energy	Reykjavík Energy	Iceland		Iceland	10.7914/SN/OR
OS	Seismological Observatory, Brasilia Brazil	University of Brasilia	Brazil	http://www.obsis.unb.br/	Brazil	
OT	OTRIONS	"University of Bari ""Aldo Moro"""	Italy	http://www.otrions.uniba.it	Italy	10.7914/SN/OT
OU	Ulaanbaatar seismic network	Institute of Astronomy and Geophysics of Mongolian Academy of Science	Mongolia	https://iag.mn	Mongolia	10.7914/6330-qb38
OV	Observatorio Vulcanológico y Sismológico de Costa Rica	Obsercatorio Vulcanológico y Sismológico de Costa Rica, Universidad Nacional	Costa Rica	http://www.ovsicori.una.ac.cr/	Costa Rica	10.7914/SN/OV
OW	Ocean Networks Canada Onshore Network	Ocean Networks Canada	Canada	http://oceannetworks.ca/	Canada	10.7914/SN/OW
OX	North-East Italy Seismic Network	Istituto Nazionale di Oceanografia e di Geofisica Sperimentale	Italy	http://rts.crs.inogs.it/	Italy	10.7914/SN/OX
OY	OGS Mobile LAB	Istituto Nazionale di Oceanografia e di Geofisica Sperimentale	Italy	http://rts.crs.inogs.it/	Italy	10.7914/SN/OY
OZ	SRC eqServer	Seismology Research Centre	Australia		Australia