Type Oceanographic cruise
Set This cruise is part of the set MOMARSAT : MONITORING THE MID ATLANTIC RIDGE
Ship Pourquoi pas ?
Ship owner Ifremer
Dates 11/06/2019 - 03/07/2019
Chief scientist(s) SARRADIN Pierre-Marie ORCID, LEGRAND Julien ORCID


IFREMER Centre de Bretagne

ZI Pointe du diable

CS 10070


+33 (0)2

DOI 10.17600/18001110

The Momarsat 2019 cruise performs the yearly maintenance of the EMSO-Azores observatory  at Lucky Strike (Mid-Atlantic Ridge). EMSO-Azores is a fixed-point buoyed observatory with a multidisciplinary approach (from geophysics and physical oceanography to ecology and microbiology).The observatory focuses on two main questions: What are the feedbacks between volcanism, deformation, seismicity, and hydrothermalism at a slow spreading mid-ocean ridge and how does the hydrothermal ecosystem couple with these sub-seabed processes? The studied area is part of a Marine Protected Area in the Portuguese EEZ.  

It is a component of the EMSO European Research Infrastructure Consortium, which coordinates observatory regional facilities in European seas (

The uncabled observing system was first deployed in 2010 in the Lucky Strike hydrothermal vent field (Mid Atlantic Ridge) at 1700 m depth. It comprises two Sea Monitoring Nodes (SEAMON) providing the energy, controlling the sensors, archiving and transmitting the data. The first node is deployed on the Lucky Strike fossil lava lake and measures the seismic activity (1 OBS) and the vertical deformation of the sea floor (2 pressure gauges). The second one is deployed at the base of the Tour Eiffel active edifice. It allows the study of the variability of a mussel assemblage and its environment (HD camera and chemical sensors, thermistor string), the microbial colonization and the chlorinity of an active vents (microbial colonization module CISICS  and BARS sensor) . The two nodes are acoustically linked to a surface relay instrumented buoy (BOREL), ensuring satellite communication to the land base station in Brest -France. The buoy is also instrumented with a meteorological station, a geodetic GPS, an OTN sensor and a pH/CTD sensor at 25m below the surface.

Data are archived, published with a doi and are available on the EMSO-Azores web page:

In addition, the observatory setup comprises several sets of autonomous instruments, whose data are collected during the yearly maintenance cruises. The autonomous instruments deployed in the area comprises 4 OBS, 2 pressure gauges, a physical oceanography mooring near the vent field, an array of temperature probes distributed in hot and diffuse vents, 6 biological or microbiological colonisation devices, 3 bottom currentmeters, a localized micro seismicity array (HYDROCTOPUS - seabed array of 4 hydrophones) and a prototype of sequential hot fluid sampler (DEAFS).

A complementary site studies program is implemented during the cruises and contributes to increase the set of accessible parameters (fluid sampling, ecological studies, survey of active and inactive areas, in situ experimentations¿) and to extend the spatial coverage of the study. An experiment to study the restoration of the bathymodiolus azoricus modiole assemblages after disturbance was initiated in 2017. Specimens of the Segonzacia mesatlantica crab and the Mirocaris fortunata shrimp are collected, kept alive and transferred to Brest at Océanopolis for the public exhibition "Abyss box" started in 2012 in collaboration between Oceanopolis, Univ. Paris Sorbonne (UPMC), Ifremer.

This year, a specific programm was initiated (TUSIG, Funded by ISBLUE) to characterize the small scale turbulence of the water column, to map the internal tide and  the  geochemical composition of the hydrothermal plume.  CTD casts, associated to water samples and VMP (Vertical Micro^profiler)  profiles  were done during the cruise,

The observatory is maintained every year during the Momarsat cruises ( All the components of the system are recovered, serviced on board and redeployed using the HOV Nautile this year.

In addition, this year, the Plouarnautes programwas set up, to create a partnership between elementary school classes and Ifremer, focused on the discovery and study of deep ecosystems, including hydrothermal vents. This new project builds on the existing resources developed in the framework of the citizen science project "Deep Sea Spy", which invites users to annotate the images acquired by sea-bottom observatories. This partnership was concretized by the creation and maintenance of a blog fed by students and scientists on board during the campaign ( This first edition of the project involved two schools this year: the school Mouez ar Mor in Ploumoguer with 5 classes corresponding to 120 students from kindergarten to CM2 and Saint Pierre school in Plougastel-Daoulas with 1 class of CP of 24 students.

The MoMARSAT and the EMSO-Azores deep sea observatory are linked to the following projects : 

  • EMSO ERIC (European Multidisciplinary Seafloor and water column Observatory,, DG J. Danobeitia) and EMSO link (PI P. Favalli, H2020 Grant agreement No. 731036).
  • ANR Luckyscale (De la chambre magmatique aux micro-habitats: dynamique des écosystèmes hydrothermaux marins profonds ¿ LuckyScales. PI M. Cannat, Grant agreement ANR-14-CE02-0008).
  • MERCES (Marine Ecosystem Restoration in Changing European Seas,, Coordinator Roberto Danovaro Università Politecnica delle Marche, Italy, H2020 grant agreement No 689518)
  • ECOREF (Ecological COnnectivity between active and inactive sites: REcolonization dynamics and Functional links. PI M. Matabos, Funding from EQUINOR).
  • Abyssbox : Aquarium pressurisé présentant au grand public depuis 2012 des crabes et crevettes prélevés sur le champ hydrothermal Lucky Strike, à Océanopolis Brest. PI D. Barthélémy.
  • ISBLUE Interdisciplinary graduate school for the blue planet  (ANR-17-EURE-0015). PI A.M. Tréguier

The data acquired during the crusie are available on line : 

- data acquired by the EMSO-Azores infrastructure :

- Video sequences recorded during the Nautile's dive :

- The cruise reports :

Published data

Chavagnac Valérie, Castillo Alain, Destrigneville Christine (2023). DEAFS – Deep-sea Autonomous and automated Fluid sampler data from the EMSO-Azores observatory, 2019.

Chavagnac Valérie, Destrigneville Christine, Castillo Alain (2023). Geochemistry of hydrothermal fluids at the Lucky Strike Hydrothermal Field data from the EMSO-Azores observatory, 2019.

Data managed by SISMER

Sampling operations





Astorch-Cardona Aina, Odin Giliane P., Chavagnac Valérie, Dolla Alain, Gaussier Hélène, Rommevaux Céline (2024). Linking Zetaproteobacterial diversity and substratum type in iron-rich microbial mats from the Lucky Strike hydrothermal field (EMSO-Azores observatory). Applied and Environmental Microbiology, 9(2), e02041-23 (20p.). Publisher's official version : , Open Access version :

Astorch-Cardona Aina, Guerre Mathilde, Dolla Alain, Chavagnac Valérie, Rommevaux Céline (2023). Spatial comparison and temporal evolution of two marine iron-rich microbial mats from the Lucky Strike Hydrothermal Field, related to environmental variations. Frontiers In Marine Science, 10, 1038192 (15p.). Publisher's official version : , Open Access version :

Allioux Maxime, Yvenou Steven, Godfroy AnneORCID, Shao Zongze, Jebbar Mohamed, Alain Karine (2022). Genome analysis of a new sulphur disproportionating species Thermosulfurimonas strain F29 and comparative genomics of sulfur-disproportionating bacteria from marine hydrothermal vents. Microbial Genomics, 8(9), 000865 (16p.). Publisher's official version : , Open Access version :

Artigue Lise, Chavagnac Valérie, Destrigneville Christine, Ferron BrunoORCID, Cathalot CecileORCID (2022). Tracking the Lithium and Strontium Isotope Signature of Hydrothermal Plume in the Water Column: A Case Study at the EMSO-Azores Deep-Sea Observatory. Frontiers in Environmental Chemistry, 3, 784385 (12p.). Publisher's official version : , Open Access version :

Marticorena JulienORCID, Matabos MarjolaineORCID, Ramirez-Llodra E., Cathalot CecileORCID, Laes AgatheORCID, Leroux Romain, Hourdez S., Donval Jean-Pierre, Sarrazin JozeeORCID (2021). Recovery of hydrothermal vent communities in response to an induced disturbance at the Lucky Strike vent field (Mid-Atlantic Ridge). Marine Environmental Research, 168, 105316 (14p.). Publisher's official version : , Open Access version :

References of Articles published in other Periodicals or Scientific Works acclaimed in the Field

Lagadec Jean Romain, Prigent SebastienORCID, Lafontaine Jean-Pierre (2019). Deep-Sea Temperature Sensor. In-Situ Readings from ROV. Sea Technology, 60(10), 17-19. Open Access version :

References of Technical Reports

Cotten Clemence, Sarrazin JozeeORCID (2022). Data management plan. DEEP-REST: Conservation and restoration of deep-sea ecosystems in the context of deep-sea mining. Deliverable D1.2.

Alix Anne-Sophie, Besson FlorianORCID, Cambon Bonavita Marie-AnneORCID, Chu Nan-Chin, Fouquet Yves, Lacroix Denis, Le Gall Morgane, Menot LenaickORCID, Pelleter EwanORCID, Sarradin Pierre-MarieORCID, Ybert Sebastien (2019). Rapport de veille scientifique et technologique relative aux ressources minérales non énergétiques des grands fonds. Convention référence 19/1000 085 entre le Ministère de la Transition Ecologique et Solidaire – Direction de l’Eau et de la Biodiversité et l’Institut français de recherche pour l’exploitation de la mer – Action 5.2. REM/2019-033. Rapport n°9.

Sarradin Pierre-MarieORCID, Legrand JulienORCID, Cannat Mathilde (2019). Compte-rendu opérationnel de la campagne Momarsat 2019. Zone de travail - Lucky Strike Infrastructure de recherche– EMSO-Açores Navire Pourquoi Pas ? Submersible Nautile. REM/RDT/19-125.

Hubert Morgane, Davy Romain, Thomas Lena (2019). Compte rendu Equipe Chimie Brest. Mission MoMARSAT 2019. N/O Pourquoi Pas ?, Atlantique Nord, EMSO Açores.

Legrand JulienORCID, Sarradin Pierre-MarieORCID, Davy Romain, Hubert Morgane, Lafontaine Jean-Pierre, Mertz Nicolas, Moreau Bertrand, Podeur Christian, Prigent SebastienORCID, Thomas Lena (2019). MOMARSAT 2019. N/O Pourquoi Pas ?, Horta – Horta, 10/06 au 04/07/2019. Infrastructure d'observation et de transmission de données de l’observatoire EMSO Açores. Compte-rendu de mission. REM/RDT/I2M/19-R128.

Rodier Philippe, Bignon Laurent (2019). Momarsat 2019 - Rapport Instrumentation.

Thesis using campaign data

Van Audenhaege LoicORCID (2023). Étude par l'imagerie de la distribution spatio-temporelle multi-échelles des communautés benthiques associées au champ hydrothermal Lucky Strike / Imaging study of the multi-scale spatio-temporal distribution of benthic communities associated with the Lucky Strike hydrothermal field. PhD Thesis, Université de Bretagne Occidentale.

Allioux Maxime (2021). Etudes physiologiques et multi-omiques de métabolismes du soufre présents dans les écosystèmes hydrothermaux : Physiological and multi-omics studies of microbial sulfur metabolisms present in hydrothermal ecosystems / Physiological and multi-omics studies of microbial sulfur metabolisms present in hydrothermal ecosystems. PhD Thesis, Université de Bretagne Occidentale.

Francois David (2021). Dynamique spatiale et temporelle des communautés microbiennes dans les édifices hydrothermaux actifs / Spatial and temporal dynamics of microbial communities in active hydrothermal vents. PhD Thesis, Université de Bretagne Occidentale.

Marticorena JulienORCID (2021). Résilience des écosystèmes hydrothermaux : résultats d’une expérience de perturbation au sein du champ hydrothermal Lucky Strike (dorsale médio-Atlantique) / Resilience of deep-sea hydrothermal vent communities : results of a disturbance experiment implemented on the Lucky Strike vent field (Mid-Atlantic ridge). PhD Thesis, Université de Bretagne Occidentale.