From the first prototypes of OBS (Ocean Bottom Seismometer) which made it possible to record thousands of submarine seismic events of the Marsili volcano, passing through the new portable seismic station PGS1, up to future projects such as the construction of the tsunami warning station in the eastern Ionian , the Early Warning project and the construction of the tidal station on the island of Ustica. We asked the head of this laboratory so active and important for INGV, Giuseppe D'Anna, to tell us all about the OBS & Earth Lab in Gibilmanna of the ETNEO Observatory.
Where was the OBS Lab born?
The OBS Lab was born at the end of 2004 with the aim of designing and manufacturing instruments for submarine seismic monitoring.
What tools did you make?
As a first activity, a broadband OBS (Ocean Bottom Seismometer) prototype was created, an instrument not present up to that moment in Italy. In 2006, this prototype was extensively tested on the Marsili submarine volcano and, in 9 days, the OBS recorded over 1000 seismic events of clearly volcanic origin and provided, for the first time, experimental evidence of the persistent hydrothermal activity of the volcano. This prototype was subsequently reproduced in 7 specimens called OBS-A.
A real success…
In 2014, 10 units of OBS-P for exploration were built to participate, together with the Spanish colleagues, in the TOMO ETNA campaign. The number of OBS-Ps will grow to 16 during 2022.
Has it been updated over the years?
The OBS-A has undergone a substantial upgrade, evolving into the OBS-B version. To date, the sum of the two versions with broadband sensors amounts to 18 units, a number that will grow to 26 during 2022.
There has therefore been a technological evolution in the field…
During the last few years the technologies developed for the marine sector have been applied to the terrestrial sector and the OBS Lab becomes the OBS & Earth Lab of Gibilmanna. Since 2017, at the request of colleagues from the Catania section, a section to which the OBS and Earth Lab will belong starting from July 2020, the ETL3D-5s sensor has been designed and built.
Other projects in progress?
In parallel, the new portable seismic station PGS1 was developed. The project had the intention of providing a low-cost solution for seismic monitoring networks, which was compact, resistant to atmospheric agents and above all had a long operational autonomy. To this end, the PGS 1 was created, a compact station, including the SeismoLog recorder, already developed for OBSPs, the ETL3D/5s seismic sensor and featuring great operational autonomy (two months).
Following a program agreement between DGS-UNMIG, INGV and Assomineraria, the "ROSPO" seismic station was built inside a pipe conductor of the "ROSPO C" platform located off the coast of Vasto (CH). The INGV staff belonging to the OBS & Earth Lab proceeded with the installation, on the seabed of the pipe conductor D, of an OBS (Nanometrics Trillium OBS 120 s – 100 Hz) which acquires the data and transfers them, in real time, via the network made available by Edison, to the INGV monitoring room in Rome. The OBS & Earth Lab took care of all the deposition logistics, designing systems and following the best practices aimed at maximizing the signal-to-noise ratio.
Last year, as part of the PON EWAS project, led by the INGV Section of Catania, following an agreement with the Kore University of Enna, a system was installed at the LEDA (Laboratory of Experimental Dynamics) of secondary calibration for seismic sensors, which shortly, with the acquisition of further instrumentation, will evolve into a system for primary calibration for the issue of the calibration certificate according to the ISO 16063-11 standard. The service will be available to companies in the private sector as well as to research institutes and bodies. This type of sensor calibration, still today, is not present in Italy.
Another ongoing activity at the OBS & Earth Lab is the extension of the seismic network to the sea, strongly desired and supported by the President Carlo Doglioni, within the PON INSEA project. This extension provides for the installation, at 5 Oil & Gas platforms managed by Eni and EDISON (today ENERGEAN), of 5 submarine multi-parametric stations equipped with broadband seismic sensor, hydrophone, absolute pressure sensor, CTD, Turbidimeter and Dissolved oxygen. These modules will be placed in the buffer zones of the platforms and connected via an electromechanical cable. The acquired signals will arrive, in real time, through VPN connections, to the INGV monitoring rooms. The supervision and control of the stations will be handled remotely by OBS & Earth Lab staff.
So many projects… what do you have in mind for the future?
In the immediate future, the OBS & Earth Lab sees its involvement in the realization of the following projects: an instrumented cable to be laid on the edge of the Sciara del Fuoco on the island of Stromboli; the construction of the tsunami warning station in the eastern Ionian Sea; the Early Warning project; the construction of the tidal station on the island of Ustica.