In October 2021, GFZ installed together with INGV Catania, Iraci and ASIR Ltd (Advances Seismic Instrumentation & Research) the very first seismic borehole broadband seismometers at two selected sites at Mt. Etna, Sicily (see Fig. 1). The installation was completed under the EU-funded project ‘SiC nano for PicoGeo’ (http://www.picogeo.eu/). Site one is located next to the Astrophysical Observatory at Serra La Nave (SLN) and site two is located in the city of Mascalucia (MAS). At each site one borehole broadband seismometer was permanently installed (cemented) at approximately 70 m depth. In approx. 1-2m distance, a second ground-level borehole 4.5 Hz Geophone was temporarily installed (sanded) at 1 m depth until July 2022 (see Fig. 2). The ground-level geophones served as a local surface reference sensor to better evaluate the increase of signal quality from surface to depth. Test data were evaluated between October 2021 and July 2022. Sensor settings were adjusted during this time period to obtain the best possible data resolution at both test sites. This data publication compiles a segment of waveform recordings utilized for the assessment of data quality from the two installed broadband borehole seismometers, along with noise plots (Fig. 3-5) illustrating the enhancements in the data quality of frequency ranges compared to surface sensors at Mt. Etna.
The Villarrica Volcano is one of the most active volcanoes in South America and is located in a major tourism region. A dense temporal seismological network was installed to investigate the volcanic seismicity and the seismic structure of the edifice with seismic traveltime tomography at high spatial resolution. The network was in operation for 2 weeks from 01.03.2012 to 14.03.2012. It consisted of 30 three-component and 45 one-component short period seismographs covering an area of about 2000 km2. The covered area has a diameter of 45 km and includes the volcanic building.
This data publication provides supplementary data to the X9_2015 network that was operated from 2015 until 2016 within the KISS experiment in the area of the Klyuchevskoy Volcanic Group. In addition, the associated seismic waveform data are archived in the GFZ GEOFON archive with the https://doi.org/10.14470/K47560642124 (Shapiro et al., 2015) and the associated Scientific Technical Report – Data (Green et al., 2021, https://doi.org/10.48440/GFZ.B103-21019). Please refer to this site for any further information.
Data in the KISS experiment was mainly recorded by Cube3 digitizers which requires a conversion into standard seismological formats including a resampling to adjust the timing of the data to the GPS signals. The data in the GEOFON archive does therefore already include some degree of processing and some loss of information contained in the GPS tags of the raw data. We therefore provide a copy of the raw data as it was retrieved from the Cube digitizers (www.gfz-potsdam.de/gipp → Instruments). Additionally, we provide raw data from the Baikal digitizers and photographs of the sites from the station collection.