First Steps Towards Site Characterization Activities at the CSTH Broad-Band Station of the Campi Flegrei’s Seismic Monitoring Network (Italy)
Abstract
1. Introduction
2. Geological Characterization
3. Specifications of the Broad-Band Station “CSTH” and the Temporary Array
Array Resolution
4. Data Analysis
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- First, we made a spectral analysis (Spectrograms and PSDs) of the entire dataset, including both seismic noise and earthquakes, to highlight possible variation from site to site. In general, the properties of seismic noise depend on proximity to populated areas or the coastline, local earthquake rate, local average wind speeds, and geological features.
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- In the second stage, we have computed spectral ratio (H/V) to assess whether the area around CSTH exhibits a homogeneous response without any significant local site effects or not. This is a basic starting point to obtain a reliable and representative velocity model of the site when seismic array techniques are applied.
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- The f-k technique was applied to the vertical component of ground motion only after confirming that the conditions of the first two processing stages were met, in order to derive the Rayleigh wave dispersion curve.
4.1. Dataset
4.2. Estimation of the Power Spectral Density (PSD)
4.3. Spectral Ratio Analysis
Temporal Representation H/V Profiles
4.4. Rayleigh Wave Dispersion Curve and Velocity Model
5. Conclusions
Author Contributions
Funding
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Site | Lat | Lon | Logistic | Acq. | Sensor | Cps | Start Registration | End Registration | Type of Soil |
---|---|---|---|---|---|---|---|---|---|
STH1 | 40.8296 | 14.1513 | Installed inside the garden of the Altamira Complex | Lunitek Atlas | Lennartz 3DLite | 100 | 05/27/2022 09:20:00 | 05/30/2022 11:10:00 | Pyroclastic deposits |
STH2 | 40.8297 | 14.1487 | Installed next to the soccer fields immediately below Pisciarelli | Lunitek Atlas | Lennartz 3DLite | 100 | 05/27/2022 08:40:00 | 05/30/2022 11:00:00 | Pyroclastic deposits |
STH3 | 40.4942 | 14.0903 | Installed in dirt road outside Ariel Car Pozzuoli | Guralp Affinity | Lennartz 3DLite | 100 | 05/27/2022 10:50:00 | 05/30/2022 10:15:00 | Pyroclastic deposits |
STH4 | 40.4948 | 14.0858 | Installed in a private garden in the same complex as STH | Lunitek Atlas | Lennartz 3DLite | 100 | 05/27/2022 08:30:00 | 05/30/2022 11:00:00 | Pyroclastic deposits |
STH5 | 40.4941 | 14.0909 | Installed in a flowerbed at Ariel Car Pozzuoli | Guralp Affinity | Lennartz 3DLite | 100 | 05/27/2022 10:30:00 | 05/30/2022 10:20:00 | Pyroclastic deposits |
CSTH | 40.8294 | 14.1493 | Solfatara Tennis Hotel | Guralp Affinity | Lennartz 3DLite | 100 | 06/04/2022 00:00:00 | Still working | Pyroclastic deposits |
CPIS | 40.8292 | 14.1468 | Campi Flegrei—Fumarola Pisciarelli | GILDA | CMG-40T-60S | 100 | 29/01/2010 | May 2023 | Pyroclastic deposits |
CSOB | 40.8264 | 14.1439 | Solfatara Bordo Cratere | GILDA | CMG-40T-60S | 100 | 11/07/2021 | Still working | Pyroclastic deposits |
Parameters | Values |
---|---|
STH length | 1 s |
LTA length | 30 s |
Minimum STA/LTA | 0.20 |
Maximum STA/LTA | 2.50 |
Window length | 250 s |
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Nardone, L.; Morelli, R.S.; Gaudiosi, G.; Liguoro, F.; Galluzzo, D.; Orazi, M. First Steps Towards Site Characterization Activities at the CSTH Broad-Band Station of the Campi Flegrei’s Seismic Monitoring Network (Italy). Sensors 2025, 25, 4787. https://doi.org/10.3390/s25154787
Nardone L, Morelli RS, Gaudiosi G, Liguoro F, Galluzzo D, Orazi M. First Steps Towards Site Characterization Activities at the CSTH Broad-Band Station of the Campi Flegrei’s Seismic Monitoring Network (Italy). Sensors. 2025; 25(15):4787. https://doi.org/10.3390/s25154787
Chicago/Turabian StyleNardone, Lucia, Rebecca Sveva Morelli, Guido Gaudiosi, Francesco Liguoro, Danilo Galluzzo, and Massimo Orazi. 2025. "First Steps Towards Site Characterization Activities at the CSTH Broad-Band Station of the Campi Flegrei’s Seismic Monitoring Network (Italy)" Sensors 25, no. 15: 4787. https://doi.org/10.3390/s25154787
APA StyleNardone, L., Morelli, R. S., Gaudiosi, G., Liguoro, F., Galluzzo, D., & Orazi, M. (2025). First Steps Towards Site Characterization Activities at the CSTH Broad-Band Station of the Campi Flegrei’s Seismic Monitoring Network (Italy). Sensors, 25(15), 4787. https://doi.org/10.3390/s25154787