Articles | Volume 12, issue 10
https://doi.org/10.5194/se-12-2351-2021
© Author(s) 2021. 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-12-2351-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
The effect of 2020 COVID-19 lockdown measures on seismic noise recorded in Romania
National Seismic Network, National Institute for Earth Physics, Magurele, 077125, Romania
Felix Borleanu
National Data Center, National Institute for Earth Physics, Magurele, 077125, Romania
Alexandru Tiganescu
Department of Research, Development and Innovation in Earth Sciences, National Institute for Earth Physics, Magurele, 077125, Romania
Technical University of Civil Engineering Bucharest, Bucharest,
020396, Romania
Natalia Poiata
National Seismic Network, National Institute for Earth Physics, Magurele, 077125, Romania
Université de Paris, Institut de Physique du Globe de Paris, CNRS,
75005 Paris, France
Raluca Dinescu
National Data Center, National Institute for Earth Physics, Magurele, 077125, Romania
Dragos Tataru
National Seismic Network, National Institute for Earth Physics, Magurele, 077125, Romania
Related authors
No articles found.
Dragos Toma-Danila, Iuliana Armas, and Alexandru Tiganescu
Nat. Hazards Earth Syst. Sci., 20, 1421–1439, https://doi.org/10.5194/nhess-20-1421-2020, https://doi.org/10.5194/nhess-20-1421-2020, 2020
Short summary
Short summary
Natural hazards have an increasing impact on transportation networks. In order to analyze it we developed Network-risk – an open toolbox for ArcGIS. The toolbox links input data such as network datasets (also OpenStreetMap – OSM – data), traffic values or segments which can be affected, determining the difficulty to reach an area and enabling evaluation of socioeconomic implications. By testing Network-risk for Bucharest we show areas difficult to reach by emergency units in earthquakes.
Related subject area
Subject area: The evolving Earth surface | Editorial team: Seismics, seismology, paleoseismology, geoelectrics, and electromagnetics | Discipline: Seismology
Linked and fully coupled 3D earthquake dynamic rupture and tsunami modeling for the Húsavík–Flatey Fault Zone in North Iceland
Earthquake monitoring using deep learning with a case study of the Kahramanmaras Turkey earthquake aftershock sequence
A borehole trajectory inversion scheme to adjust the measurement geometry for 3D travel-time tomography on glaciers
Ocean bottom seismometer (OBS) noise reduction from horizontal and vertical components using harmonic–percussive separation algorithms
Towards real-time seismic monitoring of a geothermal plant using Distributed Acoustic Sensing
Upper-lithospheric structure of northeastern Venezuela from joint inversion of surface-wave dispersion and receiver functions
A study on the effect of input data length on a deep-learning-based magnitude classifier
Multi-array analysis of volcano-seismic signals at Fogo and Brava, Cape Verde
Reflection imaging of complex geology in a crystalline environment using virtual-source seismology: case study from the Kylylahti polymetallic mine, Finland
The damaging character of shallow 20th century earthquakes in the Hainaut coal area (Belgium)
Accelerating Bayesian microseismic event location with deep learning
Strain to ground motion conversion of distributed acoustic sensing data for earthquake magnitude and stress drop determination
Regional centroid moment tensor inversion of small to moderate earthquakes in the Alps using the dense AlpArray seismic network: challenges and seismotectonic insights
Unprecedented quiescence in resource development area allows detection of long-lived latent seismicity
Seismic monitoring of urban activity in Barcelona during the COVID-19 lockdown
Seismic signature of the COVID-19 lockdown at the city scale: a case study with low-cost seismometers in the city of Querétaro, Mexico
Characterizing the oceanic ambient noise as recorded by the dense seismo-acoustic Kazakh network
Seismic evidence of the COVID-19 lockdown measures: a case study from eastern Sicily (Italy)
Sensing Earth and environment dynamics by telecommunication fiber-optic sensors: an urban experiment in Pennsylvania, USA
Effects of finite source rupture on landslide triggering: the 2016 Mw 7.1 Kumamoto earthquake
Fabian Kutschera, Alice-Agnes Gabriel, Sara Aniko Wirp, Bo Li, Thomas Ulrich, Claudia Abril, and Benedikt Halldórsson
Solid Earth, 15, 251–280, https://doi.org/10.5194/se-15-251-2024, https://doi.org/10.5194/se-15-251-2024, 2024
Short summary
Short summary
We present a suite of realistic 3D dynamic rupture earthquake–tsunami scenarios for the Húsavík–Flatey Fault Zone in North Iceland and compare one-way linked and fully coupled modeling workflows on two fault system geometries. We find that our dynamic rupture simulation on a less segmented strike-slip fault system causes local tsunami wave heights (crest to trough) of up to ~ 0.9 m due to the large shallow fault slip (~ 8 m), rake rotation (± 20°), and coseismic vertical displacements (± 1 m).
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
Short summary
Short summary
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.
Sebastian Hellmann, Melchior Grab, Cedric Patzer, Andreas Bauder, and Hansruedi Maurer
Solid Earth, 14, 805–821, https://doi.org/10.5194/se-14-805-2023, https://doi.org/10.5194/se-14-805-2023, 2023
Short summary
Short summary
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.
Zahra Zali, Theresa Rein, Frank Krüger, Matthias Ohrnberger, and Frank Scherbaum
Solid Earth, 14, 181–195, https://doi.org/10.5194/se-14-181-2023, https://doi.org/10.5194/se-14-181-2023, 2023
Short summary
Short summary
Investigation of the global Earth's structure benefits from the analysis of ocean bottom seismometer (OBS) data that allow an improved seismic illumination of dark spots of crustal and mantle structures in the oceanic regions of the Earth. However, recordings from the ocean bottom are often highly contaminated by noise. We developed an OBS noise reduction algorithm, which removes much of the oceanic noise while preserving the earthquake signal and does not introduce waveform distortion.
Jerome Azzola, Katja Thiemann, and Emmanuel Gaucher
EGUsphere, https://doi.org/10.5194/egusphere-2022-1417, https://doi.org/10.5194/egusphere-2022-1417, 2022
Preprint archived
Short summary
Short summary
Distributed Acoustic Sensing is applied to the micro-seismic monitoring of a geothermal plant. In this domain, the feasibility of managing the large flow of generated data and their suitability to monitor locally induced seismicity was yet to be assessed. The proposed monitoring system efficiently managed the acquisition, processing and saving of the data over a 6-month period. This testing period proved that the monitoring concept advantageously complements more classical monitoring networks.
Roberto Cabieces, Mariano S. Arnaiz-Rodríguez, Antonio Villaseñor, Elizabeth Berg, Andrés Olivar-Castaño, Sergi Ventosa, and Ana M. G. Ferreira
Solid Earth, 13, 1781–1801, https://doi.org/10.5194/se-13-1781-2022, https://doi.org/10.5194/se-13-1781-2022, 2022
Short summary
Short summary
This paper presents a new 3D shear-wave velocity model of the lithosphere of northeastern Venezuela, including new Moho and Vp / Vs maps. Data were retrieved from land and broadband ocean bottom seismometers from the BOLIVAR experiment.
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
Short summary
Short summary
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 %.
Carola Leva, Georg Rümpker, and Ingo Wölbern
Solid Earth, 13, 1243–1258, https://doi.org/10.5194/se-13-1243-2022, https://doi.org/10.5194/se-13-1243-2022, 2022
Short summary
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.
Michal Chamarczuk, Michal Malinowski, Deyan Draganov, Emilia Koivisto, Suvi Heinonen, and Sanna Rötsä
Solid Earth, 13, 705–723, https://doi.org/10.5194/se-13-705-2022, https://doi.org/10.5194/se-13-705-2022, 2022
Short summary
Short summary
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
Short summary
Short summary
Over the 20th century, shallow damaging seismicity occurred in and near the Hainaut coal mining area in Belgium. We provide an overview of earthquake parameters and impacts, combining felt and damage testimonies and instrumental measurements. Shallower earthquakes have a depth and timing compatible with mining activity. The most damaging events occurred deeper than the mines but could still have been triggered by mining-caused crustal changes. Our modelling can be applied to other regions.
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
Short summary
Short summary
The localization of an earthquake is affected by many uncertainties. To correctly propagate these uncertainties into an estimate of the earthquake coordinates and their associated errors, many simulations of seismic waves are needed. This operation is computationally very intensive, hindering the feasibility of this approach. In this paper, we present a series of deep-learning methods to produce accurate seismic traces in a fraction of the time needed with standard methods.
Itzhak Lior, Anthony Sladen, Diego Mercerat, Jean-Paul Ampuero, Diane Rivet, and Serge Sambolian
Solid Earth, 12, 1421–1442, https://doi.org/10.5194/se-12-1421-2021, https://doi.org/10.5194/se-12-1421-2021, 2021
Short summary
Short summary
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
Solid Earth, 12, 1233–1257, https://doi.org/10.5194/se-12-1233-2021, https://doi.org/10.5194/se-12-1233-2021, 2021
Short summary
Short summary
The Alpine mountains are known for a complex tectonic history. We shed light onto ongoing tectonic processes by studying rupture mechanisms of small to moderate earthquakes between 2016 and 2019 observed by the temporary AlpArray seismic network. The rupture processes of 75 earthquakes were analyzed, along with past earthquakes and deformation data. Our observations point at variations in the underlying tectonic processes and stress regimes across the Alps.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Cited articles
Apple: COVID-19 Mobility Trend Reports, COVID-19 Mobility Trend Reports, Apple [dataset], available at: https://covid19.apple.com/mobility, last access: 29 September 2021.
Boese, C. M., Wotherspoon, L., Alvarez, M., and Malin, P.: Analysis of
anthropogenic and natural noise from multilevel borehole seismometers in an
urban environment, Auckland, New Zealand, B. Seismol. Soc. Am., 105,
285–299, https://doi.org/10.1785/0120130288, 2015.
Cannata, A., Cannavò, F., Di Grazia, G., Aliotta, M., Cassisi, C., De Plaen, R. S. M., Gresta, S., Lecocq, T., Montalto, P., and Sciotto, M.: Seismic evidence of the COVID-19 lockdown measures: a case study from eastern Sicily (Italy), Solid Earth, 12, 299–317, https://doi.org/10.5194/se-12-299-2021, 2021.
Denolle, M. A. and Nissen-Meyer, T.: Quiet Anthropocene, quiet Earth,
Science, 369, 1299–1300, https://doi.org/10.1126/science.abd8358, 2020.
De Plaen, R. S. M., Márquez-Ramírez, V. H., Pérez-Campos, X., Zuñiga, F. R., Rodríguez-Pérez, Q., Gómez González, J. M., and Capra, L.: Seismic signature of the COVID-19 lockdown at the city scale: a case study with low-cost seismometers in the city of Querétaro, Mexico, Solid Earth, 12, 713–724, https://doi.org/10.5194/se-12-713-2021, 2021.
Dias, F. L., Assumpcao, M., Peixoto, P. S., Bianchi, M. B., Collaco, B., and
Calhau, J.: Using Seismic Noise Levels to Monitor Social Isolation: An
Example From Rio de Janeiro, Brazil, Geophys. Res. Lett., 47, 1–9,
https://doi.org/10.1029/2020GL088748, 2020.
Diaz, J., Villaseñor, A., Morales, J., Pazos, A., Córdoba, D., Pulgar, J.,
García-Lobón, J. L., Harnafi, M., Carbonell, R., and Gallart, J.: TopoIberia
Seismic Working Group: Background noise characteristics at the IberArray
broadband seismic network, B. Seismol. Soc. Am., 100, 618–628,
https://doi.org/10.1785/0120090085, 2010.
Diaz, J., Ruiz, M., Sánchez-Pastor, P. S., and Romero, P.: Urban
Seismology: On the origin of earth vibrations within a city, Sci. Rep., 7,
15296, https://doi.org/10.1038/s41598-017-15499-y, 2017.
Diaz, J., Ruiz, M., and Jara, J.-A.: Seismic monitoring of urban activity in Barcelona during the COVID-19 lockdown, Solid Earth, 12, 725–739, https://doi.org/10.5194/se-12-725-2021, 2021.
Evangelidis, C. P. and Melis, N. S.: Ambient noise levels in Greece as
recorded at the Hellenic Unified Seismic Network, B. Seismol. Soc. Am., 102,
2507–2517, https://doi.org/10.1785/0120110319, 2012.
Google: COVID-19 Community Mobility Report, COVID-19 Community Mobility Report, Google [dataset], available at: https://www.google.com/covid19/mobility?hl=en, last access: 29 September 2021.
Grecu, B., Neagoe, C., and Tataru, D.: Seismic noise characteristics at the
Romanian broadband seismic network, J. Earthq. Eng., 16, 644–661,
https://doi.org/10.1080/13632469.2011.642931, 2012.
Grecu, B., Neagoe, C., Tataru, D., Borleanu, F., and Zaharia, B.: Analysis
of seismic noise in the Romanian-Bulgarian cross-border region, J. Seismol.,
22, 1275–1292, https://doi.org/10.1007/s10950-018-9767-4, 2018.
Green, D. N., Bastow, I. D., Dashwood, B., and Nippress, S. E. J.:
Characterizing Broadband Seismic Noise in Central London, Seismol. Res.
Lett., 88, 113–124, https://doi.org/10.1785/0220160128, 2017.
Groos, J. C. and Ritter, J. R. R.: Time domain classification and
quantification of seismic noise in an urban environment, Geophys. J. Int.,
179, 1213–1231, https://doi.org/10.1111/j.1365-246X.2009.04343.x, 2009.
Hasselmann, K.: A statistical analysis of the generation of microseisms, Rev.
Geophys., 1, 177–210, https://doi.org/10.1029/RG001i002p00177, 1963.
Krischer, L., Megies, T., Barsch, R., Beyreuther, M., Lecocq, T., Caudron,
C., and Wassermann, J.: ObsPy: A bridge for seismology into the scientific
Python ecosystem, [code], Comput. Sci. Discov., 8, 1–17,
https://doi.org/10.1088/1749-4699/8/1/014003, 2015.
Lecocq, T., Hicks, S. P., Van Noten, K., van Wijk, K., Koelemeijer, P., De
Plaen, R. S. M., Massin, F., Hillers, G., Anthony, R. E., Apoloner, M.-T.,
Arroyo-Solórzano, M., Assink, J. D., Buyukakpınar, P., Cannata, A.,
Cannavo, F., Carrasco, S., Caudron, C., Chaves, E. J., Cornwell, D. G.,
Craig, D., den Ouden, O. F. C., Diaz, J., Donner, S., Evangelidis, C. P.,
Evers, L., Fauville, B., Fernandez, G. A., Giannopoulos, D., Gibbons, S. J.,
Girona, T., Grecu, B., Grunberg, M., Hetényi, G., Horleston, A., Inza,
A., Irving, J. C. E., Jamalreyhani, M., Kafka, A., Koymans, M. R., Labedz,
C. R., Larose, E., Lindsey, N. J., McKinnon, M., Megies, T., Miller, M. S.,
Minarik, W., Moresi, L., Marquez-Ramirez, V. H., Mollhoff, M., Nesbitt, I.
M., Niyogi, S., Ojeda, J., Oth, A., Proud, S., Pulli, J., Retailleau, L.,
Rintamaki, A. E., Satriano, C., Savage, M. K., Shani-Kadmiel, S., Sleeman,
R., Sokos, E., Stammler, K., Stott, A. E., Subedi, S., Sørensen, M. B.,
Taira, T., Tapia, M., Turhan, F., van der Pluijm, B., Vanstone, M., Vergne,
J., Vuorinen, T. A. T., Warren, T., Wassermann, J., and Xiao, H.: Global
quieting of high-frequency seismic noise due to COVID-19 pandemic lockdown
measures, Science, 369, 1338–1343, https://doi.org/10.1126/science.abd2438,
2020a.
Lecocq, T., Massin, F., Satriano, C., Vanstone, M., and Megies, T.:
SeismoRMS – A simple Python/Jupyter Notebook package for studying seismic
noise changes Version 1.0, Zenodo [code], https://doi.org/10.5281/zenodo.3820046,
2020b.
Long, L. T.: Investigation of Seismic Road Noise, Georgia Institute of
Technology, Atlanta, Georgia, 35 pp., 1971.
Longuet-Higgins, M. S.: A theory of the origin of microseisms, Philos. T. Roy. Soc. A, 243, 1–35, https://doi.org/10.1098/rsta.1950.0012, 1950.
Marmureanu, A., Ionescu, C., Grecu, B., Toma-Danila, D., Tiganescu, A.,
Neagoe, C., Toader, V., Craifaleanu, I. G., Dragomir, C. S., Meita, V.,
Liashchuk, O. I., Dimitrova, L., and Ilies, I.: From National to
Transnational Seismic Monitoring Products and Services in the Republic of
Bulgaria, Republic of Moldova, Romania, and Ukraine, Seismol. Res. Lett., 92, 1685–1703,
https://doi.org/10.1785/0220200393, 2021.
Marzorati, S. and Bindi, D.: Ambient noise levels in north central Italy,
Geochem. Geophy. Geosy., 7, Q09010, doi:10.1029/2006GC001256, 2006.
McNamara, D. E., and Buland, R. P.: Ambient noise levels in the continental
United States, B. Seismol. Soc. Am., 94, 1517–1527,
https://doi.org/10.1785/012003001, 2004.
Mihai, A., Moldovan, I. A., Toader, V. E., Radulian, M., and Placinta, A.
O.: Correlations between geomagnetic anomalies recorded at Muntele Rosu
seismic Observatory (Romania) and seismicity of Vrancea zone, Rom. Rep.
Phys., 71, 1–12, 2019.
Nakata, N., Snieder, R., Tsuji, T., Larner, K., and Matsuoka, T.: Shear wave
imaging from traffic noise using seismic interferometry by cross-coherence,
Geophysics, 76, 97–106, https://doi.org/10.1190/geo2010-0188.1, 2011.
Poli, P., Boaga, J., Molinari, I., Cascone, V., and Boschi, L.: The 2020
coronavirus lockdown and seismic monitoring of anthropic activities in
Northern Italy, Sci. Rep., 10, 1–8,
https://doi.org/10.1038/s41598-020-66368-0, 2020.
QGIS.org: QGIS Geographic Information System, QGIS Association, QGIS.org [code], available at: http://www.qgis.org, last access: 29 September 2021.
Sheen, D. H., Shin, J. S., Kang, T. S., and Baag, C. E.: Low frequency
cultural noise, Geophys. Res. Lett., 36, L17314,
https://doi.org/10.1029/2009GL039625, 2009.
Tiganescu, A., Balan, E. S. F., Toma-Danila, D., and Apostol, B. F.:
Preliminary analysis of data recorded on instrumented buildings from
Bucharest area during the 28th October 2018 Vrancea earthquake, in:
Proceedings of the 19th International Multidisciplinary Scientific
GeoConference SGEM, Albena, Bulgaria, 30 June–6 July 2019, 19, 897–904,
https://doi.org/10.5593/sgem2019/1.1/S05.111, 2019.
Tiganescu, A., Grecu, B., and Craifaleanu, I. G.: Dynamic Identification for
Representative Building Typologies: Three Case Studies from Bucharest Area,
Civil Eng. J., 6, 418–430, https://doi.org/10.28991/cej-2020-03091480, 2020.
van Wijk, K., Chamberlain, C. J., Lecocq, T., and Van Noten, K.: Seismic monitoring of the Auckland Volcanic Field during New Zealand's COVID-19 lockdown, Solid Earth, 12, 363–373, https://doi.org/10.5194/se-12-363-2021, 2021.
Xiao, H., Eilon, Z. C., Ji, C., and Tanimoto, T.: COVID-19 Societal Response
Captured by Seismic Noise in China and Italy, Seismol. Res. Lett., 91,
2757–2768, https://doi.org/10.1785/0220200147, 2020.
Yabe, S., Imanishi, K., and Nishida, K.: Two-step seismic noise reduction
caused by COVID-19 induced reduction in social activity in metropolitan
Tokyo, Japan, Earth Planets Space, 72, 167,
https://doi.org/10.1186/s40623-020-01298-9, 2020.
Short summary
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.
The reduced human activity during the lockdown has also provided a good opportunity for stations sited in noisy urban areas to record earthquake signals that would not have been recorded under normal conditions.
The lockdown imposed in Romania to prevent the spread of COVID-19 has significantly impacted...