Articles | Volume 13, issue 8
https://doi.org/10.5194/se-13-1243-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-13-1243-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Aug 2022
Research article |
| 04 Aug 2022
| 04 Aug 2022
Multi-array analysis of volcano-seismic signals at Fogo and Brava, Cape Verde
Carola Leva
CORRESPONDING AUTHOR
Institute of Geosciences, Goethe University Frankfurt,
Altenhöferallee 1, 60438 Frankfurt am Main, Germany
Georg Rümpker
Institute of Geosciences, Goethe University Frankfurt,
Altenhöferallee 1, 60438 Frankfurt am Main, Germany
Ingo Wölbern
Institute of Geosciences, Goethe University Frankfurt,
Altenhöferallee 1, 60438 Frankfurt am Main, Germany
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Carola Leva, Georg Rümpker, and Ingo Wölbern
Nat. Hazards Earth Syst. Sci., 20, 3627–3638, https://doi.org/10.5194/nhess-20-3627-2020, https://doi.org/10.5194/nhess-20-3627-2020, 2020
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Often, an abrupt increase in shallow seismicity at volcanoes is seen as an indicator for magmatic intrusions into the upper crust. If no eruption occurs and the seismic activity stops, this is called a failed eruption. Here, we report a failed eruption of Brava, Cabo Verde, in August 2016. We remotely monitored the seismicity of Brava with a seismic array, operating from October 2015 to December 2016. Other episodes with increased seismicity around the island were also observed during the study.
Wei Li, Megha Chakraborty, Jonas Köhler, Claudia Quinteros-Cartaya, Georg Rümpker, and Nishtha Srivastava
Solid Earth, 15, 197–213, https://doi.org/10.5194/se-15-197-2024, https://doi.org/10.5194/se-15-197-2024, 2024
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Seismic phase picking and magnitude estimation are crucial components of real-time earthquake monitoring and early warning. Here, we test the potential of deep learning in real-time earthquake monitoring. We introduce DynaPicker, which leverages dynamic convolutional neural networks for event detection and arrival-time picking, and use the deep-learning model CREIME for magnitude estimation. This workflow is tested on the continuous recording of the Turkey earthquake aftershock sequences.
Fabian Limberger, Georg Rümpker, Michael Lindenfeld, and Hagen Deckert
Solid Earth, 14, 859–869, https://doi.org/10.5194/se-14-859-2023, https://doi.org/10.5194/se-14-859-2023, 2023
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Wind turbines that are located close to a seismometer produce ground tremors that can increase the noise level at the seismic station. Using numerical models, we analyse the effectivity of borehole installations to reduce this impact. We study effects of geophysical parameters on the borehole effectivity and validate our modelling approach with data from real boreholes. Boreholes are effective in reducing the impact of wind turbines; however, this depends on the wavelength of the seismic wave.
Megha Chakraborty, Wei Li, Johannes Faber, Georg Rümpker, Horst Stoecker, and Nishtha Srivastava
Solid Earth, 13, 1721–1729, https://doi.org/10.5194/se-13-1721-2022, https://doi.org/10.5194/se-13-1721-2022, 2022
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Earthquake magnitude is a crucial parameter in defining its damage potential, and hence its speedy determination is essential to issue an early warning in regions close to the epicentre. This study summarises our findings in an attempt to apply deep-learning-based classifiers to earthquake waveforms, particularly with respect to finding an optimum length of input data. We conclude that the input length has no significant effect on the model accuracy, which varies between 90 %–94 %.
Fabian Limberger, Michael Lindenfeld, Hagen Deckert, and Georg Rümpker
Solid Earth, 12, 1851–1864, https://doi.org/10.5194/se-12-1851-2021, https://doi.org/10.5194/se-12-1851-2021, 2021
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Frequency-dependent amplitude decays of seismic signals induced by wind turbines are determined from (up to) 6 months of continuous recordings measured along an 8 km profile located at a wind farm in Bavaria, Germany. The radiation pattern and amplitude decay of the induced signals are accounted for by an analytical approach that includes path and source effects. This approach is generalized to predict the characteristic seismic radiation patterns of arbitrary wind farm configurations.
Manvendra Singh and Georg Rümpker
Solid Earth, 11, 2557–2568, https://doi.org/10.5194/se-11-2557-2020, https://doi.org/10.5194/se-11-2557-2020, 2020
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Using seismic array methods, 63 events were located in the Rodrigues–CIR region, not reported by any global network, most of them being off the ridge axis. The lack of seismicity along this section of the CIR, as observed from global data and this study, can possibly be attributed to the presence of partially molten mantle beneath Rodrigues Ridge. The results will be of interest for a broad range of geoscientists interested in the tectonic evolution of Indian Ocean and plume–crust interaction.
Carola Leva, Georg Rümpker, and Ingo Wölbern
Nat. Hazards Earth Syst. Sci., 20, 3627–3638, https://doi.org/10.5194/nhess-20-3627-2020, https://doi.org/10.5194/nhess-20-3627-2020, 2020
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Often, an abrupt increase in shallow seismicity at volcanoes is seen as an indicator for magmatic intrusions into the upper crust. If no eruption occurs and the seismic activity stops, this is called a failed eruption. Here, we report a failed eruption of Brava, Cabo Verde, in August 2016. We remotely monitored the seismicity of Brava with a seismic array, operating from October 2015 to December 2016. Other episodes with increased seismicity around the island were also observed during the study.
Related subject area
Subject area: The evolving Earth surface | Editorial team: Seismics, seismology, paleoseismology, geoelectrics, and electromagnetics | Discipline: Seismology
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Wei Li, Megha Chakraborty, Jonas Köhler, Claudia Quinteros-Cartaya, Georg Rümpker, and Nishtha Srivastava
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Acoustic waves are suitable to analyse the physical properties of the subsurface. For this purpose, boreholes are quite useful to deploy a source and receivers in the target area to get a comprehensive high-resolution dataset. However, when conducting such experiments in a subsurface such as glaciers that continuously move, the boreholes get deformed. In our study, we therefore developed a method that allows an analysis of the ice while considering deformations.
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Michal Chamarczuk, Michal Malinowski, Deyan Draganov, Emilia Koivisto, Suvi Heinonen, and Sanna Rötsä
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In passive seismic measurement, all noise sources from the environment, such as traffic, vibrations caused by distant excavation, and explosive work from underground mines, are utilized. In the Kylylahti experiment, receivers recorded ambient noise sources for 30 d. These recordings were subjected to data analysis and processing using novel methodology developed in our study and used for imaging the subsurface geology of the Kylylahti mine area.
Thierry Camelbeeck, Koen Van Noten, Thomas Lecocq, and Marc Hendrickx
Solid Earth, 13, 469–495, https://doi.org/10.5194/se-13-469-2022, https://doi.org/10.5194/se-13-469-2022, 2022
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Bogdan Grecu, Felix Borleanu, Alexandru Tiganescu, Natalia Poiata, Raluca Dinescu, and Dragos Tataru
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The lockdown imposed in Romania to prevent the spread of COVID-19 has significantly impacted human activity across the country. By analyzing the ground vibrations recorded at seismic stations, we were able to monitor the changes in human activity before and during the lockdown.
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Alessio Spurio Mancini, Davide Piras, Ana Margarida Godinho Ferreira, Michael Paul Hobson, and Benjamin Joachimi
Solid Earth, 12, 1683–1705, https://doi.org/10.5194/se-12-1683-2021, https://doi.org/10.5194/se-12-1683-2021, 2021
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Itzhak Lior, Anthony Sladen, Diego Mercerat, Jean-Paul Ampuero, Diane Rivet, and Serge Sambolian
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The increasing use of distributed acoustic sensing (DAS) inhibits the transformation of optical fibers into dense arrays of seismo-acoustic sensors. Here, DAS strain records are converted to ground motions using the waves' apparent velocity. An algorithm for velocity determination is presented, accounting for velocity variations between different seismic waves. The conversion allows for robust determination of fundamental source parameters, earthquake magnitude and stress drop.
Gesa Maria Petersen, Simone Cesca, Sebastian Heimann, Peter Niemz, Torsten Dahm, Daniela Kühn, Jörn Kummerow, Thomas Plenefisch, and the AlpArray and AlpArray-Swath-D working groups
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Rebecca O. Salvage and David W. Eaton
Solid Earth, 12, 765–783, https://doi.org/10.5194/se-12-765-2021, https://doi.org/10.5194/se-12-765-2021, 2021
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Small earthquakes in Alberta and north-east British Columbia have been previously ascribed to industrial activities. The COVID-19 pandemic forced almost all these activities to stop for ~ 4 months. However, unexpectedly, earthquakes still occurred during this time. Some of these earthquakes may be natural and some the result of earthquakes > M6 occurring around the world. However, ~ 65 % of the earthquakes detected may be the remnants of previous fluid injection in the area (
latent seismicity).
Jordi Diaz, Mario Ruiz, and José-Antonio Jara
Solid Earth, 12, 725–739, https://doi.org/10.5194/se-12-725-2021, https://doi.org/10.5194/se-12-725-2021, 2021
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During the COVID-19 pandemic lockdown, the city of Barcelona was covered by a network of 19 seismometers. The results confirm that the quieting of human activity during lockdown has resulted in a reduction of seismic vibrations. The different lockdown phases in Barcelona are recognized consistently at most of the seismic stations. Our contribution demonstrates that seismic noise can be used as a free and reliable tool to monitor human activity in urban environments.
Raphael S. M. De Plaen, Víctor Hugo Márquez-Ramírez, Xyoli Pérez-Campos, F. Ramón Zuñiga, Quetzalcoatl Rodríguez-Pérez, Juan Martín Gómez González, and Lucia Capra
Solid Earth, 12, 713–724, https://doi.org/10.5194/se-12-713-2021, https://doi.org/10.5194/se-12-713-2021, 2021
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COVID-19 pandemic lockdowns in countries with a dominant informal economy have been a greater challenge than in other places. This motivated the monitoring of the mobility of populations with seismic noise throughout the various phases of lockdown and in the city of Querétaro (central Mexico). Our results emphasize the benefit of densifying urban seismic networks, even with low-cost instruments, to observe variations in mobility at the city scale over exclusively relying on mobile technology.
Alexandr Smirnov, Marine De Carlo, Alexis Le Pichon, Nikolai M. Shapiro, and Sergey Kulichkov
Solid Earth, 12, 503–520, https://doi.org/10.5194/se-12-503-2021, https://doi.org/10.5194/se-12-503-2021, 2021
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Seismic and infrasound methods are techniques used to monitor natural events and explosions. At low frequencies, band signal can be dominated by microbaroms and microseisms. The noise observations in the Kazakh network are performed and compared with source and propagation modeling. The network is dense and well situated for studying very distant source regions of the ambient noise. The prospects are opening for the use of ocean noise in solid Earth and atmosphere tomography.
Andrea Cannata, Flavio Cannavò, Giuseppe Di Grazia, Marco Aliotta, Carmelo Cassisi, Raphael S. M. De Plaen, Stefano Gresta, Thomas Lecocq, Placido Montalto, and Mariangela Sciotto
Solid Earth, 12, 299–317, https://doi.org/10.5194/se-12-299-2021, https://doi.org/10.5194/se-12-299-2021, 2021
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During the COVID-19 pandemic, most countries put in place social interventions, aimed at restricting human mobility, which caused a decrease in the seismic noise, generated by human activities and called anthropogenic seismic noise. In densely populated eastern Sicily, we observed a decrease in the seismic noise amplitude reaching 50 %. We found similarities between the temporal patterns of seismic noise and human mobility, as quantified by mobile-phone-derived data and ship traffic data.
Tieyuan Zhu, Junzhu Shen, and Eileen R. Martin
Solid Earth, 12, 219–235, https://doi.org/10.5194/se-12-219-2021, https://doi.org/10.5194/se-12-219-2021, 2021
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We describe the Fiber Optic foR Environmental SEnsEing (FORESEE) project in Pennsylvania, USA, the first continuous-monitoring distributed acoustic sensing (DAS) fiber array in the eastern USA. With the success of collecting 1 year of continuous DAS recordings using nearly 5 km of telecommunication fiber underneath the university campus, we conclude that DAS along with telecommunication fiber will potentially serve the purpose of continuous near-surface seismic monitoring in populated areas.
Sebastian von Specht, Ugur Ozturk, Georg Veh, Fabrice Cotton, and Oliver Korup
Solid Earth, 10, 463–486, https://doi.org/10.5194/se-10-463-2019, https://doi.org/10.5194/se-10-463-2019, 2019
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We show the landslide response to the 2016 Kumamoto earthquake (Mw 7.1) in central Kyushu (Japan). Landslides are concentrated to the northeast of the rupture, coinciding with the propagation direction of the earthquake. This azimuthal variation in the landslide concentration is linked to the seismic rupture process itself and not to classical landslide susceptibility factors. We propose a new ground-motion model that links the seismic radiation pattern with the landslide distribution.
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Short summary
The seismicity of Fogo and Brava, Cape Verde, is dominated by volcano-tectonic earthquakes in the area of Brava and volcanic seismic signals, such as hybrid events, on Fogo. We locate these events using a multi-array analysis, which allows the localization of seismic events occurring outside the network and of volcanic signals lacking clear phases. We observe exceptionally high apparent velocities for the hybrid events located on Fogo. These velocities are likely caused by a complex ray path.
The seismicity of Fogo and Brava, Cape Verde, is dominated by volcano-tectonic earthquakes in...
