The 9H Seismic Network, 2007–2011
-
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restricted.
- Cite as:
- Wolfram Geissler; Mechita Schmidt-Aursch; Luis Matias; Davide Embriaco; Carlos Corela; Paolo Favali; Nevio Zitellini; Wilfried Jokat (2025): Integrated observations from NEAR shore sourcES of Tsunamis: towards an early warning system (NEAREST). GFZ Data Services. Other/Seismic Network. doi:10.14470/4U972300.
- Network code:
- 9H
- Type:
- Temporary
- Network dates†:
- 2007-01-01 to 2011-12-31
- Data time range‡:
- 2007–2009
- Terms of use:
- Creative Commons Attribution 4.0 International
Available since 2025-07-08
- Institution(s):
- Alfred-Wegener-Institut, Bremerhaven
- Creator(s):
- Wolfram Geissler; Mechita Schmidt-Aursch; Luis Matias; Davide Embriaco; Carlos Corela; Paolo Favali; Nevio Zitellini; Wilfried Jokat (LEGACY)
- Description*:
- Integrated observations from NEAR shore sourcES of Tsunamis: towards an early warning system (NEAREST)
- Abstract:
- 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.
* Description is taken from seismic metadata, and may not match the preferred title for citations. - DataCite metadata:
- HTML | JSON | XML | INSPIRE
- Seismic metadata:
- fdsnws-station
- Network KML file:
Extended Network Information for network 9H [hide/show]
- Creator(s):
-
Geissler, Wolfram
a;
Schmidt-Aursch, Mechita
a;
Matias, Luis
b;
Embriaco, Davide
c;
Corela, Carlos
b;
Favali, Paolo
c;
Zitellini, Nevio
d;
Jokat, Wilfried
a
- Title:
- Integrated observations from NEAR shore sourcES of Tsunamis: towards an early warning system (NEAREST)
- Publisher:
- GFZ Data Services
- Resource Type:
- Other/Seismic Network
- Network DOI:
- doi:10.14470/4U972300
- Related Reference(s):
-
- Geissler, Wolfram H; Schmidt-Aursch, Mechita; Matias, Luis; Embriaco, Davide; Corela, Carlos; Favali, Paolo; Zitellini, Nevio; Jokat, Wilfried (2025). Project NEAREST: DEPAS ocean-bottom seismometer operations in the Gulf of Cadiz in 2007-2008. PANGAEA (DOI registration in progress).
- Corela, C.; Loureiro, A.; Duarte, J. L.; Matias, L.; Rebelo, T.; Bartolomeu, T. (2023). The effect of deep ocean currents on ocean-bottom seismometers records. Natural Hazards and Earth System Sciences, 23(4), 1433-1451. doi:10.5194/nhess-23-1433-2023
- Pereira, A.; Harris, D.; Tyack, P.; Matias, L. (2020). Fin whale acoustic presence and song characteristics in seas to the southwest of Portugal. The Journal of the Acoustical Society of America, 147(4), 2235-2249. doi:10.1121/10.0001066
- Pereira, A.; Harris, D.; Tyack, P.; Matias, L. (2020). On the use of the Lloyd's Mirror effect to infer the depth of vocalizing fin whales. The Journal of the Acoustical Society of America, 148(5), 3086-3101. doi:10.1121/10.0002426
- Corela, C.; Silveira, G.; Matias, L.; Schimmel, M.; Geissler, W. H. (2017). Ambient seismic noise tomography of SW Iberia integrating seafloor-and land-based data. Tectonophysics, 700, 131-149. doi:10.1016/j.tecto.2017.02.012
- Schmidt-Aursch, Mechita; Haberland, Christian (2017). DEPAS (Deutscher Geräte-Pool für amphibische Seismologie): German Instrument Pool for Amphibian Seismology. Journal of large-scale research facilities JLSRF. doi:10.17815/jlsrf-3-165
- Silva, S.; Terrinha, P.; Matias, L.; Duarte, J. C.; Roque, C.; Ranero, C. R.; Geissler W. H.; Zitellini, N. (2017). Micro-seismicity in the Gulf of Cadiz: Is there a link between micro-seismicity, high magnitude earthquakes and active faults?. Tectonophysics, 717, 226-241. doi:10.1016/j.tecto.2017.07.026
- Matias, L.; Harris, D. (2015). A single-station method for the detection, classification and location of fin whale calls using ocean-bottom seismic stations. The Journal of the Acoustical Society of America, 138(1), 504-52035. doi:10.1121/1.4922706
- Harris, D.; Matias, L.; Thomas, L.; Harwood, J.; Geissler, W. H. (2013). Applying distance sampling to fin whale calls recorded by single seismic instruments in the northeast Atlantic. The Journal of the Acoustical Society of America, 134(5), 3522-3535. doi:10.1121/1.4821207
- Monna, S.; Cimini, G. B.; Montuori, C.; Matias, L.; Geissler, W. H.; Favali, P. (2013). New insights from seismic tomography on the complex geodynamic evolution of two adjacent domains: Gulf of Cadiz and Alboran Sea. Journal of Geophysical Research: Solid Earth, 118(4), 1587-16013535. doi:10.1029/2012JB009607
- Geissler, W. H.; Matias, L.; Stich, D.; Carrilho, F.; Jokat, W.; Monna, S.; A. IbenBrahim; F. Mancilla; M.-A. Gutscher; V. Sallarè; Zitellini, N. (2010). Focal mechanisms for sub-crustal earthquakes in the Gulf of Cadiz from a dense OBS deployment. Geophysical Research Letters, 37(18). doi:10.1029/2010GL044289
- Carrara, G. et al. (2008). NEAREST 2008 CRUISE PRELIMINARY REPORT R/V URANIA, 1st Aug 2008-04th Sept 2008. Technical Report ISMAR, Cruise Report. doi:10.26383/CNR-ISMAR.2008.1
- Place(s):
- Gulf of Cadiz
- Subject(s)a:
- Tsunami
- GCMD keyword(s):
- Funding Reference(s):
- European Commission (037110)
Station List for Network Code 9H
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Database last updated at 2026 Jun 12 12:16:07
