FocusX2

Type Oceanographic cruise
Set This cruise is part of the set FOCUS
Ship Pourquoi pas ?
Ship owner Ifremer
Dates 13/01/2022 - 28/01/2022
Chief scientist(s) GUTSCHER Marc-André ORCID

GEO-OCEAN - UMR 6538

IFREMER - Technopôle Brest-Iroise

IUEM - Rue Dumont d'Urville

29280 Plouzané

https://www.geo-ocean.fr/
DOI 10.17600/18001255
Objective

The FocusX2 cruise project aims to set up an essential complementary experimental device for the FOCUS project (Advanced Grant project funded by the European Research Council to the tune of 3.5 M€ 2018-2023). As a reminder, the FOCUS project seeks to validate the technique of measuring seabed deformations using an optical fibre (laser reflectometry). The first part of the FocusX1 cruise project (classified P2 in 2019) took place in Oct. 2020 (8 days on the N/O Pourquoi Pas?). We carried out a site survey using micro-bathymetric mapping and visual observations (by camera) with the ROV Victor6000. Using the ROV, the 6 km Focus fibre optic cable was connected to the cabled observatory (TSS = Test Site South of the Catania Institute of Physics INFN-LNS) at a depth of 2050m. With the ROV, using a dedicated plough, we deployed a 6 km fibre optic cable and successfully buried it at 20cm depth for about half of the length. We also deployed 8 seabed geodetic stations to try and calibrate the observations of the fibre optic cable.

 During the FocusX2 cruise it was planned to :

  1. Deploy 30 OBS (15 French and 15 German) to complement the INGV terrestrial seismic network to monitor seismic activity on active faults and even the subduction fault plane;
  2. Carry out sediment sounder profiles (Chirp) and AUV sediment sounder profiles to specify the geometry of active faults, to image recent sedimentary deformations and to help in the selection of sedimentary coring sites;
  3. Acoustic download of data from the 8 geodetic stations deployed in Oct 2020 on the northern termination of the North Alfeo Fault and potentially from the 6 geodetic stations deployed by Geomar in Nov 2021, on the continuation of the fault on the submarine flank of Etna;
  4. The collection of sedimentary cores to conduct a paleoseismological study of turbidities, characterize the mechanical properties of the slope sediments, and analyze the interstitial fluids, coming from hydrothermal circulations through the fault that could modify its rheological behavior (serpentinization);
  5. It was also planned to carry out a 2-day study of fluids in the water column by CTD Rosette.

Following the Covid-19 cluster on board the Pourquoi Pas on 3 January 2022, the duration of the cruise in the area was reduced from 18 days to 9 days. Thus, the objectives had to be revised downwards. The work of CTD Rosette was cancelled. The number of OBS deployed was reduced to 20. The download of seabed geodesy data was greatly reduced. There has also been a failure of the majority of the French seabed geodesy stations (Ixblue acoustic beacons purchased with ERC FOCUS project funds) which will require ROV intervention to recover them.

Data managed by SISMER

Sampling operations

Dives

Bibliography

References of Technical Reports

Dupont Pauline (2022). MISSION FocusX2 N/O Pourquoi pas ? 13 au 27 Janvier 2022, Mer Ionienne. Compte rendu d’acquisition des données de sondeur de sédiment. PDG/REM/GEOOCEAN/ANTIPOD-20220203-01. https://archimer.ifremer.fr/doc/00756/86808/


References of International Seminar Communications

Barreca, G., Gaillot, A., Klingelhoefer, F., Dupont, P., Lenhof, E., Coussin, V., Dominguez, S., Gutscher, M.-A., (2023). Ultra-high resolution (micro-bathymetric mapping and sub-bottom profiling) imaging of an active strike-slip fault, the North Alfeo Fault, offshore Catania, Eastern Sicily (Ionian Sea, Central Mediterranean) EGU Annual Meeting, Vienna, 24-28 April 2023.

Gutscher, M.-A., Dominguez, S., Gaillot, A., Barreca, G., (2023). Detailed structure of the North Alfeo strike slip fault offshore Eastern Sicily: ultra-high resolution micro-bathymetry and analog modeling. RST (Réunion des Sciences de la Terre) Meeting, Rennes, 30 Oct. - 3 Nov., 2023.

Margheriti Lucia, Moretti Milena, Piccinini Davide, Latorre Diana, Alparone Salvatore, Cocina Ornella, Costanzo Antonio, Gutscher Marc-Andre, La Rocca Mario, Marchetti Alessandro, Murphy Shane, Nardi Anna, Pastori Marina, Focus Working Group* (2023). Earthquake monitoring in Italy: integration of a temporary seismic experiment into national real-time surveillance, the example of FocusX temporary land-network. IUGG2023 - 28th IUGG General Assembly. 11 to 20 July 2023, Berlin. https://archimer.ifremer.fr/doc/00847/95887/

Royer, J.-Y., Lenhof, E., Poitou, C., Ballu, V., Coulombier, T., Dausse, D., Sakic, P., Jamieson, G., Morvan, P.-Y., and Gutscher, M.-A., (2022). Active Strike-Slip Fault Monitoring Using Marine Geodesy, Offshore Mt Etna, Sicily (Italy), EGU General Assembly 2022, 23-27 May 2022, EGU22-8264, https://doi.org/10.5194/egusphere-egu22-8264.

References of National Seminar Communications

Belliard, H., Babonneau, N., Coussin, V., Cattaneo, A., Bachèlery P., Gutscher M.-A., (2023). Facies evolution and sedimentary processes on the Calabrian accretionnary wedge, from Focus zone to the abyssal plain over the last 20,000 years. 28ème réunion des Sciences de la Terre, RST Rennes, Oct./Nov. 2023.

Gutscher, M.-A., Dominguez, S., Gaillot, A., Barreca, G., (2023). Detailed structure of the North Alfeo strike slip fault offshore Eastern Sicily: ultra-high resolution micro-bathymetry and analog modeling. RST (Réunion des Sciences de la Terre) Meeting, Rennes, 30 Oct. - 3 Nov., 2023.

Gutscher, M.-A., Hage, S., Babonneau, N., Dennielou, B., Silva Jacinto, R., Garreau, P. Cattaneo, A., (2023). Radial furrows observed offshore Catania (East Sicily): evidence for downslope sea-bottom currents?. RST (Réunion des Sciences de la Terre) Meeting, Rennes, 30 Oct. - 3 Nov., 2023.

Coussin, V., Babonneau N., Gutscher M.-A, Briend M., Cattaneo A., Bachelery P., (2022). Tectonic and sedimentation interactions along the North-Alfeo fault compartment (northwestern Ionian Sea) through the study of the last 30 kyrs of submarine gravity deposits off Etna volcano. 18ème Congrès de l'ASF (Association des Sédimentologues Français), Brest, Sept 2022.

DEA or MASTER 2 using campaign data

Belliard, H., (2023). Evolution des faciès et processus sédimentaire sur le prisme d'accrétion calabrais (zone FOCUS) à la plaine abyssale Ionienne sur les derniers 20 ka. Mémoire de stage de Master 2 Géosciences Océan, Brest.

Briend, M., (2022). Analyse sédimentologique et stratigraphique d'une carotte sédimentaire prélevée le long de la faille de Nord-Alféo à l'Est de la Sicile. Mémoire de stage de Master 1 Géosciences Océan, Brest.

Thesis using campaign data

Edgar Lenhof (2024) thèse avec soutenence prévue en Oct. 2024, intitulé: Etude cinématique de la faille Nord Alfeo (marge Est-Sicilienne) par observation géodésique fond de mer