2026-08-04T15:21:30Zhttp://doidb.wdc-terra.org/oaip/oai

oai:doidb.wdc-terra.org:83692025-08-06T12:22:41ZDOIDBDOIDB.SEISNET

false4DOIDB.SEISNET 10.14470/4U972300 Geissler, Wolfram Wolfram Geissler 0000-0001-6807-555X Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany Schmidt-Aursch, Mechita Mechita Schmidt-Aursch 0000-0002-2393-4514 Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany Matias, Luis Luis Matias 0000-0002-8086-4874 University of Lisbon, Lisbon, Portugal Embriaco, Davide Davide Embriaco 0000-0001-7943-7341 National Institute of Geophysics and Volcanology, Rome, Italy Corela, Carlos Carlos Corela 0000-0002-0150-2286 University of Lisbon, Lisbon, Portugal Favali, Paolo Paolo Favali 0000-0002-0810-0263 National Institute of Geophysics and Volcanology, Rome, Italy Zitellini, Nevio Nevio Zitellini 0000-0001-9920-8968 Institute of Marine Science, Bologna, Italy Jokat, Wilfried Wilfried Jokat 0000-0002-7793-5854 Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany GFZ Data Services 2025 GFZ Helmholtz-Zentrum für Geoforschung GEOFON Data Centre geofon@gfz.de Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany University of Lisbon, Lisbon, Portugal National Institute of Geophysics and Volcanology, Rome, Italy Institute of Marine Science, Bologna, Italy Tsunami EARTH SCIENCE > SOLID EARTH > TECTONICS > EARTHQUAKES EARTH SCIENCE > OCEANS > MARINE GEOPHYSICS Instruments > In Situ/Laboratory Instruments > Magnetic/Motion Sensors > Seismometers Instruments > In Situ/Laboratory Instruments > Profilers/Sounders > Acoustic Sounders > HYDROPHONES In Situ Land-based Platforms > GEOPHYSICAL STATIONS/NETWORKS Geophysics Passive seismic Seismometers Hydrophones Velocity MiniSEED DEPAS Pool OBS Temporary 2007-09-01(start of data collection) 2025-05-06(accepted for archiving) 2025-06-12(data and metadata completely submitted) 2025-07-08(actually published/made available on server) 2025-07-08(creation of DOI) 2025-07-08(end of embargo period) en Seismic Network Creative Commons Attribution 4.0 International 10.17815/jlsrf-3-165 10.26383/CNR-ISMAR.2008.1 10.1029/2010GL044289 10.1121/1.4821207 10.1029/2012JB009607 10.1121/1.4922706 10.1016/j.tecto.2017.02.012 10.1016/j.tecto.2017.07.026 10.1121/10.0001066 10.1121/10.0002426 10.5194/nhess-23-1433-2023 https://doi.pangaea.de/10.1594/PANGAEA.983719 https://geofon.gfz.de/waveform/archive/response/9H/2007_2011 457GB .mseed XML The NEARESTproject (Integrated observations from NEAR shore sourcES of Tsunamis:  towards an early warning system) aimed at the identification and characterization of potential near-shore sources of tsunamis in the Gulf of Cadiz. This area is well known from the catastrophic earthquake and tsunami that destroyed Lisbon and several other places mainly along the EastAtlantic coast on November 1st, 1755. One of the project's work packages dealed with monitoring of recent seismic activity in the Gulf of Cadiz area. For this purpose 24 broadband ocean-bottom seismometers (OBS) from the German DEPAS instrument pool were deployed for 11 months in addition to the GEOSTAR multi-parameter deep-sea observatory and two temporary land stations in Portugal. The GEOSTAR observatory and the 24 OBS were deployed and recovered during two expeditions with RV Urania in 2007 and 2008. The OBSs consist of  three‐component Guralp CMG‐40T‐OBS seismometers and HighTech HTI‐04‐PCA/ULF hydrophones. A wide range of signals was recorded, ncluding teleseismic, regional and local earthquakes, and low‐frequency (∼20 Hz) vocalization of fin whales.  The GEOSTAR  observatory was again deployed between 2009 and 2011. The Portuguese temporary land station PDRG was additionally recording during the NEAREST project. Originally, the position of recovery on deck was taken to calculate the mean coordinate of the OBS at depth from deployment and recovery coordinates. In most cases the difference in coordinates between deployment and recovery is very small (table 3 and 4 in Carrara et al., 2008). For two stations, the location at the seafloor could be measured by triangulation (Carrara et al., 2008). Due to experience of other experiments over the years, we finally suggest to use the deployment coordinates as the station coordinates for all stations that could not be tri-angulated. The clocks were synchronized with GPS time before the deployment and if possible again after the recovery. Unfortunately, most of the batteries were empty at the end of the recording period. That either made it impossible to realize the second synchronisation (skew time measurement) or in some case also caused erroneous synchronisations. Therefore, the internal clock drift was estimated by ambient noise analysis (Corela, 2014). The internal clock drifts were corrected using a linear interpolation method. Generally, the data quality is very good, especially for the intended study of local and regional earthquakes. Studies relying on wideband seismological recordings can also be carried out. The sensor package and noise conditions hamper the use for broadband and very broadband applications. Unfortunately, also not all channels operated properly, therefore hampering the use of multi-component methods for the relevant stations. We thank the captain E. Gentile, crew, G. Carrara, and all participants of the R/V URANIA expeditions in 2007 and 2008. We are grateful to all people and institutions involved in the NEAREST project. Waveform data is available from the GEOFON data centre, under network code 9H. -11.5 -8.0 35.0 38.0 Gulf of Cadiz European Commission https://ror.org/00k4n6c32 037110