{"id":{"repo_id":"potsdam-thes","oai_identifier":"oai:kobv.de-opus4-uni-potsdam:61379"},"canonical_url":"https://search.dev.ndltd.org/etd/potsdam-thes/oai:kobv.de-opus4-uni-potsdam:61379","repository":{"repo_id":"potsdam-thes","name":"Universität Potsdam - Thes","base_url":"https://publishup.uni-potsdam.de/opus4-ubp/oai"},"display":{"title":"Seismic site characterization using broadband and DAS ambient vibration measurements on Mt Etna, Italy","abstract":"Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.","abstract_html":"Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.","abstract_has_math":false,"creators":["Pätzel, Jonas"],"institution":"Universität Potsdam","degree_name":null,"degree_level":"master","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Jousset, Philippe","Ohrnberger, Matthias"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2023,"date_issued":"2023-08-08","date_published":"2023-08-08","updated_at":"2026-07-24T03:52:13Z","subjects":["site characterization","Etna","DAS","ambient vibration","seismic noise","H/V","HVSR","velocity model","SPAC","MSPAC","spatial autocorrelation","Piano delle Concazze","site effects","microzonation","volcanic tremor","joint inversion","ortsverteile faseroptische Dehnungsmessung","Ätna","horizontal-vertikales Spektralverhältnis","räumliche Autkorrelationsmethode","modifizierte räumliche Autkorrelationsmethode","Bodenunruhe","gemeinsame Inversion","Mikrozonierung","seismisches Rauschen","Ortscharakterisierung","Ortseffekte","räumliche Autokorrelation","Geschwindigkeitsmodell","vulkanischer Tremor"],"languages":[],"rights":["CC-BY-SA - Namensnennung, Weitergabe zu gleichen Bedingungen 4.0 International"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://publishup.uni-potsdam.de/frontdoor/index/index/docId/61379","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Jousset, Philippe","Ohrnberger, Matthias"]},{"key":"dc:creator","label":"Author","values":["Pätzel, Jonas"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:publisher","label":"Institution","values":["Universität Potsdam"]},{"key":"dc:type","label":"Dc Type","values":["masterThesis"]},{"key":"thesis:degree_level","label":"Degree Level","values":["master"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Universität Potsdam"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["site characterization","Etna","DAS","ambient vibration","seismic noise","H/V","HVSR","velocity model","SPAC","MSPAC","spatial autocorrelation","Piano delle Concazze","site effects","microzonation","volcanic tremor","joint inversion","ortsverteile faseroptische Dehnungsmessung","Ätna","horizontal-vertikales Spektralverhältnis","räumliche Autkorrelationsmethode","modifizierte räumliche Autkorrelationsmethode","Bodenunruhe","gemeinsame Inversion","Mikrozonierung","seismisches Rauschen","Ortscharakterisierung","Ortseffekte","räumliche Autokorrelation","Geschwindigkeitsmodell","vulkanischer Tremor"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["CC-BY-SA - Namensnennung, Weitergabe zu gleichen Bedingungen 4.0 International"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.","Sowohl die räumliche Autokorrelations-Methode (SPAC) als auch die Methode der horizontal-vertikal Spektralverhältnisse (H/V) sind wichtige Instrumente bei der seismischen Charakterisierung des Untergrundes mittels Bodenunruhe. In der vorliegenden Arbeit werden beide Techniken angewandt, um die Geschwindigkeitsstruktur der Piano delle Concazze Ebene auf dem Ätna zu untersuchen. Die Aufzeichnungen vulkanischen Tremors auf einem Array aus 26 Breitband-Seismometern werden prozessiert und starke Schwankungen des H/V Verhältnisses, insbesondere während Zeiten erhöhter vulkanischer Aktivität werden festgestellt. Die räumliche Verteilung der H/V Frequenzpeaks bildet eine geologische Struktur im nordöstlichen Bereichs des Untersuchungsgebietes ab. Diese wird als der alte Rand der Ellittico Caldera interpretiert. Die H/V-Methode wird um die kombinierte Verarbeitung von Geschwindigkeitsaufzeichnungen des Breitband-Arrays und faseroptischen Dehnungmessungen (distributed acoustic sensing, DAS) erweitert. Hierfür werden die Daten eines 1,5 km langen Glasfaserkabels, mit welchem das Seismometer-Array zusammen installiert wurde, genutzt. Erhöhte Werte der maximalen Amplitude der berechneten Spektralverhältnisse, stimmen mit der Lage bekannter Verwerfungen im Gebiet überein. Das Ergebnis deutet auf einen bisher nicht aufgezeichneten Verlauf einer der Verwerfungszonen hin. Die Interpretaion der Strukturen stimmt überein mit den Ergebnissen einer Geomagnetik-Studie der Piano delle Concazze. Mithilfe des Neighborhood-Algorithmus werden die räumlichen Autokorrelationskurven der modifizierten SPAC, sowohl einfach als auch in Kombination mit den H/V Frequenzpeaks, invertiert. So werden schließlich 1D Modelle der S-Wellengeschwindigkeit abgeleitet. Diese stimmen weitgehend überein mit den Resultaten anderer Studien und bestätigen darüberhinaus die Ergebnisse der DAS-Aufzeichnungen."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Seismic site characterization using broadband and DAS ambient vibration measurements on Mt Etna, Italy"]}]}],"canonical_facts":{"dc:contributor":["Jousset, Philippe","Ohrnberger, Matthias"],"dc:creator":["Pätzel, Jonas"],"dc:description.abstract":["Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.","Sowohl die räumliche Autokorrelations-Methode (SPAC) als auch die Methode der horizontal-vertikal Spektralverhältnisse (H/V) sind wichtige Instrumente bei der seismischen Charakterisierung des Untergrundes mittels Bodenunruhe. In der vorliegenden Arbeit werden beide Techniken angewandt, um die Geschwindigkeitsstruktur der Piano delle Concazze Ebene auf dem Ätna zu untersuchen. Die Aufzeichnungen vulkanischen Tremors auf einem Array aus 26 Breitband-Seismometern werden prozessiert und starke Schwankungen des H/V Verhältnisses, insbesondere während Zeiten erhöhter vulkanischer Aktivität werden festgestellt. Die räumliche Verteilung der H/V Frequenzpeaks bildet eine geologische Struktur im nordöstlichen Bereichs des Untersuchungsgebietes ab. Diese wird als der alte Rand der Ellittico Caldera interpretiert. Die H/V-Methode wird um die kombinierte Verarbeitung von Geschwindigkeitsaufzeichnungen des Breitband-Arrays und faseroptischen Dehnungmessungen (distributed acoustic sensing, DAS) erweitert. Hierfür werden die Daten eines 1,5 km langen Glasfaserkabels, mit welchem das Seismometer-Array zusammen installiert wurde, genutzt. Erhöhte Werte der maximalen Amplitude der berechneten Spektralverhältnisse, stimmen mit der Lage bekannter Verwerfungen im Gebiet überein. Das Ergebnis deutet auf einen bisher nicht aufgezeichneten Verlauf einer der Verwerfungszonen hin. Die Interpretaion der Strukturen stimmt überein mit den Ergebnissen einer Geomagnetik-Studie der Piano delle Concazze. Mithilfe des Neighborhood-Algorithmus werden die räumlichen Autokorrelationskurven der modifizierten SPAC, sowohl einfach als auch in Kombination mit den H/V Frequenzpeaks, invertiert. So werden schließlich 1D Modelle der S-Wellengeschwindigkeit abgeleitet. Diese stimmen weitgehend überein mit den Resultaten anderer Studien und bestätigen darüberhinaus die Ergebnisse der DAS-Aufzeichnungen."],"dc:format.medium":["application/pdf"],"dc:publisher":["Universität Potsdam"],"dc:rights":["CC-BY-SA - Namensnennung, Weitergabe zu gleichen Bedingungen 4.0 International"],"dc:subject":["site characterization","Etna","DAS","ambient vibration","seismic noise","H/V","HVSR","velocity model","SPAC","MSPAC","spatial autocorrelation","Piano delle Concazze","site effects","microzonation","volcanic tremor","joint inversion","ortsverteile faseroptische Dehnungsmessung","Ätna","horizontal-vertikales Spektralverhältnis","räumliche Autkorrelationsmethode","modifizierte räumliche Autkorrelationsmethode","Bodenunruhe","gemeinsame Inversion","Mikrozonierung","seismisches Rauschen","Ortscharakterisierung","Ortseffekte","räumliche Autokorrelation","Geschwindigkeitsmodell","vulkanischer Tremor"],"dc:title":["Seismic site characterization using broadband and DAS ambient vibration measurements on Mt Etna, Italy"],"dc:type":["masterThesis"],"thesis:degree_level":["master"],"thesis:institution_name":["Universität Potsdam"]},"updated_at":"2026-07-24T03:52:13Z"}