Cultural activity and impact of extreme weather events revealed by ambient seismic noise and perspective on quick clay failure monitoring in Oslo, Norway

Engineering Geology, Год журнала: 2025, Номер unknown, С. 107936 - 107936

Опубликована: Фев. 1, 2025

Язык: Английский

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Analyzing Volcanic, Tectonic, and Environmental Influences on the Seismic Velocity from 25 Years of Data at Mount St. Helens

Seismological Research Letters, Год журнала: 2024, Номер 95(5), С. 2674 - 2688

Опубликована: Июль 17, 2024

Abstract We estimate changes in the seismic velocity (dv/v) from 25 years of ambient noise recorded at Mount St. Helens (MSH). At MSH, availability stations frequently due to station failure and installation new stations. Therefore, it is difficult combine relative measurements that do not span same time space. tackle this challenge by developing a spatial imaging algorithm normalize all ∼1400 dv/v series onto one grid. Thereby, we obtain time-dependent change maps MSH region, which analyze with help auxiliary observations, such as ground position (i.e., Global Navigation Satellite System [GNSS]), weather data, environmental regional seismicity. In series, find variety dynamics caused volcanic, tectonic, forcing. With initiation MSH’s 2004–2008 volcanic crisis, exhibits significant increase, link deflation plumbing system, also observed on GNSS data. Between 2013 2018, when seismicity levels are elevated, lower velocities depth. This phase followed an episode quiescence, accompanied increases close zone. suggest reinflation magmatic system after eruption lasting until about 2017. Afterward, activity subsurface reduces, thereby decreasing pressure increasing velocity. Fluctuating groundwater may dominate seasonal cycles series. A contrasting response between high-elevation edifice foothill valleys indicate surface freezing inhibits infiltration higher altitudes.

Язык: Английский

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Machine Learning Analysis of Seismograms Reveals a Continuous Plumbing System Evolution Beneath the Klyuchevskoy Volcano in Kamchatka, Russia

Journal of Geophysical Research Solid Earth, Год журнала: 2024, Номер 129(3)

Опубликована: Март 1, 2024

Abstract Volcanoes produce a variety of seismic signals and, therefore, continuous seismograms provide crucial information for monitoring the state volcano. According to their source mechanism and signal properties, seismo‐volcanic can be categorized into distinct classes, which works particularly well short transients. Applying classification approaches long‐duration containing volcanic tremors, characterized by varying characteristics, proves challenging due complex nature these signals. That makes it difficult attribute them single process questions feasibility classification. In present study, we consider whole time series as valuable about plumbing system (the combination structure activity distribution). The considered data are year‐long recorded at individual stations near Klyuchevskoy Volcanic Group (Kamchatka, Russia). With scattering network Uniform Manifold Approximation Projection (UMAP), transform two‐dimensional representation (a seismogram atlas), helps us identify sudden changes in properties. We observe an ever‐changing wavefield that relate continuously evolving system. Through additional data, variations various volcano including transitions from deep shallow activity, reactivation, weak during quiet times, eruptive activity. atlases serve visual tool analyzing extensive series, allowing associate specific atlas areas, indicative similar with activities

Язык: Английский

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Examining 22 Years of Ambient Seismic Wavefield at Mount St. Helens

Seismological Research Letters, Год журнала: 2024, Номер 95(5), С. 2622 - 2636

Опубликована: Июнь 12, 2024

Abstract An increase in seismic activity precedes most volcanic eruptions. Whereas event-based forecasting approaches have been successful, some eruptions remain unanticipated, resulting casualties and damage. Our study leverages the recent advancements ambient field seismology. We explore features extracted from continuous fields using traditional methods, for example, peak ground velocity, acceleration, root mean square, median real-time amplitude measurement, novel methods (displacement ratio spectral width). In addition, we unsupervised learning of higher order wavelet scattering networks. find that combining all was necessary to disentangle effects sources structural changes at Mount St. Helens. Although wavefield-based approach does not yield additional or more significant precursory signals than Helens, our demonstrates wavefield provides supplementary information, mainly about complements methods. The offers insights into long-lasting processes. enhanced wave attenuation correlating with geochemical measurements. interpret this as ongoing changes, such dome growth evolution conduit system. On annual decadal timescales, seasonal shallow subsurface groundwater fluctuations, corroborated by observations nearby Spirit Lake level. This multimethod Helens sheds light on a system’s underlying dynamics structure.

Язык: Английский

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A Frequency Domain Methodology for Quantitative Evaluation of Diffuse Wavefield With Applications to Seismic Imaging

Journal of Geophysical Research Solid Earth, Год журнала: 2024, Номер 129(5)

Опубликована: Май 1, 2024

Abstract Ambient Noise Imaging (ANI) of subsurface structures relies on seismic interferometry diffuse wavefields. However, the lack effective methods to quantify and identify highly waves hampers applications ANI, particularly in evaluating attenuation monitoring structural changes with high temporal resolution. Conventional ANI approaches require data normalization, which effectively suppresses non‐diffuse component large amplitude but also results significant loss phase information continuous records. In this study, we propose a frequency domain method quantitatively evaluate degree diffuseness wavefields by analyzing their statistical characteristics modal amplitudes for stationarity randomness. Tests synthetic waveform field nodal records show that proposed can distinguish between waveforms either single‐ or three‐component data. As an application, 60‐s‐long coda local M 2.2 earthquake recorded dense array San Jacinto Fault Zone, successfully extract high‐quality dispersion curve Q ‐value without performing normalization. These are consistent those obtained conventional assess correlation coherency Green's function, modeling ballistic generated road traffic. Our advance imaging velocity as well scientific studies engineering applications.

Язык: Английский

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Short- and long-term velocity variations and strain evolution at Ischia (ITALY) and their implications for dynamics of the hydrothermal system

Authorea (Authorea), Год журнала: 2024, Номер unknown

Опубликована: Март 5, 2024

In active volcanic systems, the elevated pressurization of fluids and movement melt materials have an enormous influence on stress-state rocks their mechanical behavior. We use seismic ambient noise to evaluate static velocity variations related long-term deformation, dynamic changes associated with 2017 Casamicciola earthquake (Mw 3.9), in complex Ischia Island (Italy). Our study reveals a significant reduction mostly near-surface damage, permanent drop near red zone, that we posit be documented landslides subsidence observed immediately after earthquake. also report positive linear trend variations, sensitive generalized contraction Caldera revealed geodetic modeling. results suggest depressurization shallow hydrothermal system, through degassing along faults or sills.

Язык: Английский

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The KISS Network in 2015–2016: Catalogs and Comparison of the Processing Results with Operational Estimates from the Permanent Network

Физика земли, Год журнала: 2024, Номер 2, С. 146 - 160

Опубликована: Май 23, 2024

As part of the international collaboration several research groups from Russia, France, and Germany, 77 temporary seismic stations were installed in summer 2015 for one-year period to conduct a detailed study deep structure Earth’s crust upper mantle region Klyuchevskoi Volcano Group (KGV) Kamchatka Peninsula. One results KISS experiment (Klyuchevskoi Investigation – Seismic Structure an extraordinary volcanic system) was final catalog joint data permanent network Branch Geophysical Survey Russian Academy Sciences (KB GS RAS). The comprises 2136 events, including 560 which lacked sufficient correct processing. .xlsx format station bulletin .isf are presented supplementary material paper. A comparative analysis conducted on solutions two catalogs: one obtained solely KB RAS another denser integrated with stations.

Язык: Английский

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The KISS Network in 2015–2016: Catalogs and Comparison of Processing Results with Operational Estimates from Permanent Network

Izvestiya Physics of the Solid Earth, Год журнала: 2024, Номер 60(2), С. 300 - 313

Опубликована: Апрель 1, 2024

Язык: Английский

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Monitoring seismic velocity changes at Campi Flegrei (Italy) using seismic noise interferometry

Journal of Volcanology and Geothermal Research, Год журнала: 2024, Номер unknown, С. 108199 - 108199

Опубликована: Окт. 1, 2024

Язык: Английский

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Short‐ and Long‐Term Seismic Velocity Variations and Strain Evolution at Ischia (Italy): Implications for Dynamics of the Hydrothermal System

Geophysical Research Letters, Год журнала: 2024, Номер 51(23)

Опубликована: Дек. 6, 2024

Abstract In active volcanic systems, the elevated pressurization of fluids and movement molten materials influence stress state mechanical behavior rocks, but direct measurement these processes related evolution rocks properties is difficult. By studying seismic velocity variations, we quantify physical changes in induced by long‐term deformation dynamic associated with 2017 Casamicciola earthquake (M w 3.9) complex Ischia Island, Italy. Our study reveals a significant reduction (∼0.2%), primarily due to near‐surface damage, permanent drop linked documented landslides subsidence observed immediately after earthquake. We also identified positive linear trend indicative generalized contraction Caldera, as revealed geodetic modeling. results suggest depressurization shallow hydrothermal system through degassing along faults or sills.

Язык: Английский

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