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.
Seismological experiment at Strokkur from 2020" is a seismological experiment realized at the most active geyser on Iceland by Eva Eibl (University of Potsdam) in collaboration with Gylfi P. Hersir formerly at ISOR Iceland. The geyser is part of the Haukadalur geothermal area in south Iceland, which contains numerous geothermal anomalies, hot springs, and basins (Walter et al., 2018). Strokkur is a pool geyser and has a silica sinter edifice with a water basin on top, which is about 12m in diameter with a central tube of more than 20m depth. The aim of the seismic experiment is to monitor eruptions of Strokkur geyser from March 2020 using three broadband seismic stations (Nanometrics Trillium Compact 120s). Sensors were buried at distances of 38.8m (GE4, SE), 47.3m (GE3, SW), and 42.5m (GE2, N) from Strokkur center. Within this time period about 1 month of data is missing due to power outages. At any other times at least one station recorded the eruptions. From this dataset, converted to MSEED using Pyrocko, currently a catalogue of 506,131 water fountains was determined and further investigated in Eibl et al. (2025). In addition, Eibl et al. (2025) assessed the effect of the weather on the system including the bubble trap suspected at around 24 m depth by Eibl et al. (2021). Waveform data are available from the GEOFON data centre, under network code 2Z.
This ocean-bottom seismometer deployment is part of an interdisciplinary project examining the Aurora hydrothermal vent field in an attempt to understand its fluid circulation. A total of 8 ocean bottom seismometers modified for the operation in sea ice covered oceans was deployed around Aurora vent field at the intersection of Gakkel Ridge and Lena Trough in the Fram Strait. The aim of the experiment was to monitor seismicity related to the hydrothermal circulation system and to reveal potentially heat reservoirs devoid of seismicity. The network consisted of 8 DEPAS Lobster type broadband OBS. Instruments were free-fall deployed and spaced by about 5-8 km. Their position at the seafloor is known to within few meters from ultrashort baseline positioning system Posidonia. The OBS recorded continuously at 100 Hz for up to 12 months between end of July 2022 and mid July 2023. One instrument (AUR02) had an unreliable seismometer records due to levelling problems. Skew values were obtained for all stations and ranged between -18 s and 12.3 s. Clock drift in this experiment was partially nonlinear. After the skew correction, a nonlinear time drift for stations AUR02, AUR04, AUR06, AUR08 was determined using noise cross-correlation. A best-fit correction was obtained by using skew-corrected station AUR01 as reference station for stations AUR04 and AUR08, while skew-corrected station AUR03 served as reference for stations AUR02 and AUR06. Station specific phase residuals obtained from a manually picked catalog of 492 events were used to further validate the clock drift corrections. For AUR04 a nonlinear phase residual drift was observed and, subsequently, the applied drift polynomial was manually adjusted to minimize resulting residuals. Waveform data are available from the GEOFON data centre under network code 4V.
A network of 209 continuously running digital seismic stations equipped with short-period geophones (200 stations) and broadband sensors (9 stations) was deployed in an area of ~14 x ~14 km in the Lausitz (Saxony, Germany) for a period of ~5 weeks. The main objectives were 1) to create a 3-D model of the subsurface (shear wave velocity; ambient noise tomography) using the ambient seismic noise field and 2) to investigate the spatio-temporal distribution of the seismic noise (and noise sources). The project is related to the preparations for the construction of a ‘Low Seismic Lab’ (as part of the German Center for Astrophysics, DZA) and potentially the Einstein Telescope. Waveform data is available from the GEOFON data centre, under network code 9I.
This is the first deployment of a teleseismic broadband array consisting of 12 three-component stations with an aperture of about 50 km in the deep ocean in about 5000 m water depth. The data can be compared with two other deployments on Madeira and in western Portugal mainland which had similar array layouts and recording time spans (network Y7). The broadband data enable furthermore analysis of the crust and upper mantle beneath the array near to the Gloria fault, a major transform fault in the North Atlantic. Recordings of numerous local and regional earthquakes make a precise location of active structures possible. Waveform data is available from the GEOFON data centre, under network code 3J.
Temporary stations of the Goethe University Frankfurt as contribution to the virtual network _EIFELLNX. Waveform data is available from the GEOFON data centre, under network code 6X.
This network of sixteen geophones and six broadbands was installed in Kåfjord, Troms og Finnmark, Norway, to study two rockslides: Njárgavárri and Indre Nordneset. Each study site had three broadbands from September 2023 to June 2025. In addition, were installed and recording: September – November 2023: six geophones on each site; April – August 2024: four geophones at Njárgavárri and ten at Indre Nordneset. The geophones were installed locally around the rockslides while the broadbands were installed one to a few kilometers from the rockslides (except for one of them directly at Indre Nordneset). The geophones in Njárgavárri were first installed as two triangular antennas of four stations each (three in triangle and one in the middle) and were then replaced by a small aperture array around the most active part of the unstable slope. The goal was to record all activities: rock falls, cracking and creeping movements. In Indre Nordneset, the geophone stations were placed in a small aperture array all around the main scarp and surface of failure to record the cracking activity. The geophones are of type 3-D Geophone PE-6/B with DATA-CUBE3 (built-in GPS). The broadbands are of type STS-2.5 with EDR-10 digitizers. Sampling frequency was 400 Hz for geophone stations, 200 Hz broadbands. Gain was at 16 (15.258789 nV/count) for the geophone stations, set on high (100 nV/bit) for the broadband stations. Waveform data is available from the GEOFON data centre, under network code 8I.
- Installation of 29 short-period seismometers between Copiapo and Taltal to monitor seismic events - The deployment was between February 2023 and June 2023 - Registering continuously 250 SPS - Onshore component of research cruise SO297 with RV Sonne. Waveform data is available from the GEOFON data centre, under network code 5R.
The Illgraben is a 10 km² steep side valley located in Switzerland. This active debris flow catchment supplies 5-15% of the total sediment load of the Rhône River upstream of Lake Geneva. The 30-80° steep catchment slopes host frequent rock falls and slides. From 2012 to 2014, a network of up to ten Nanometrics Trillium Compact 120s broadband seismometers, sampled by Digos DataCube³ext loggers at 200 Hz (and later by centaur), was deployed in and around the catchment to monitor distributed geomorphic activity. Waveform data is available from the GEOFON data centre, under network code 9J, and is fully open.
The Eifel Large-N Seismic Network is a concentric network of about 80km aperture around the Laacher See. Instrumentation consists of broad band seismometers, short period instruments (1Hz eigenfrequency) and 4.5Hz geophones. While the broadband and short period stations cover the area rather homogeneously for about 12 month, the geophone stations were moved after 6 month from a layout focussed on the closer vicinity of the Laacher See onto a line crossing the network from south-west to north-east with a dense station spacing. The goal of the experiment is the structural investigation of the feeding system of the East Eifel and a detailed study of the tectonic and volcanic seismic activity in this area. Waveform data is available from the GEOFON data centre, under network code 6E.
| Origin | Count |
|---|---|
| Wissenschaft | 147 |
| Type | Count |
|---|---|
| unbekannt | 147 |
| License | Count |
|---|---|
| geschlossen | 46 |
| offen | 65 |
| unbekannt | 36 |
| Language | Count |
|---|---|
| Englisch | 147 |
| Resource type | Count |
|---|---|
| Keine | 147 |
| Topic | Count |
|---|---|
| Boden | 146 |
| Lebewesen und Lebensräume | 57 |
| Luft | 44 |
| Mensch und Umwelt | 147 |
| Wasser | 44 |
| Weitere | 147 |