The Azores Node - esonet-noe.org€¦ · hydrothermal vents mine heat over 50 km along-axis ? - Or are they associated with transient magmatic events ? - How do hydrothermal convective

The Azores Node

outline of talk :

• principal objectives

• who are the actors so far & what has been achieved ?

• what experiments are currently running ?

M. Cannat / presentation of Azores Node / ESONET All Regions Workshop Barcelona, sept 5-7 2007

The Azores NodeAn observatory of deep sea

ecosystems and activeprocesses related to

seismicity, volcanism, andhydrothermal circulations in

the Azores region Lucky Strike hydrothermal fieldMid-Atlantic Ridge

Pico Volcano - the Azores

• Principal objectivesEu

Af

NA


@ Ifremer

Seismic and Volcanic Risk in the Azores

Earthquakes and Volcanoes had atremendous impact in Azoreseconomy over the five centuries of itshistory.

The ESONET node will :

> Extend the on-land seismicmonitoring network off-shore andaddress the links between risk on-shore and plate boundary processes;

> Promote a collective consciousnessin the population, for a betterunderstanding of earth processes bothas risk factors and as potentialresources;

Pico Volcano - the Azores


Seamounts harbour importantfishing resources, both asresident and visitor species, and“priority conservation”invertebrate species like coldwater corals and deep-seasponges.

Hydrothermal vents harbourinvaluable resources in terms ofbiodiversity and biotechnologypotential

The ESONET Azores node willprovide needed holisticinformation concerning thesehabitats, essential for anecosystem-based management ofthe area.

Deep sea ecosystems in the Azores region

M. Cannat / presentation of Azores Node / ESONET All Regions Workshop Barcelona, sept 5-7 2007@ Ifremer

Dynamics of hydrothermal ecosystems…….

Mid-Atlantic Ridgehydrothermal fields : the

MoMAR* project* Monitoring the Mid-Atlantic Ridge

RAINBOW

Ultramafic-hosted

Depth 2300 m

LUCKY STRIKE

Basaltic-hosted

Depth 1700 m

MENEZ GWEN

Basaltic-hosted

Depth 830 m

pillow lava - basalt


@ Ifremer

@ Ifremer@ Ifremer

@ Ifremer


« geological » forcing


0.5-0.9

2.5

CH4

mmol/kg

30-8620.02-0.73.5-3.7

170-364

L. Strike

24000162.8365Rainbow

Fe

µmol/kg

H2

mmol/kg

pHT°C

Charlou et al., 2002

SerpentinizedSerpentinizedultramafic rockultramafic rock

Why is host rock important (1) ?


basaltbasalt

Global fluxes

Elderfield and Schultz, 1996


Iron oxidation as an additional (+CH4 + sulphides)

energy source in the vents ecosystem ?

Rimicaris exoculata: a newtype of symbiosis based on

iron oxidation

Zbinden et al., 2004

RainbowWhy is host rock important (2) ?



@ Ifremer

0

2km

A simple 2-dimensionalmodel ….

* ~ 1 nuclear power plant reactor

Estimated energy flux for one large Mid-

Atlantic Ridge vent field : ~ 1000 MW*

…. This is about the estimated time-averaged flux for 50 km of ridge !

Dynamics of hydrothermal ecosystems …… geological forcing

- Do Mid-Atlantic Ridgehydrothermal vents mine heat over50 km along-axis ?

- Or are they associated withtransient magmatic events ?

- How do hydrothermal convectivecells work ?

- What rocks do they encounter ?


A complex 3-dimensional settingLucky Strike :

Segment-scaleapproach and basalt-hosted ecosystem onactive axial volcano

Rainbow :

Ultramafic-hostedecosystem on active

detachment fault

The two MoMAR focus sites for long-term observation :


Extensive site surveys and cruise-based time-seriesExtensive site surveys and cruise-based time-serieswork since the early 90s (FP3, FP4, FP5 projectswork since the early 90s (FP3, FP4, FP5 projectsMARFLUX, AMORES and VENTOX & national& nationalprograms).programs).

MoMAR initiative launched in 1998 in Lisbon. MoMAR initiative launched in 1998 in Lisbon. ……. site. sitesurvey cruises continuesurvey cruises continue…… LabHortaLabHorta facility set up facility set upin Faialin Faial……..

Observatory-dedicated work funded by EC FP6Observatory-dedicated work funded by EC FP6EXOCET-DEXOCET-D ( (STREP 2003-2007STREP 2003-2007), and ), and MoMARnetMoMARnet((Marie Curie RTN 2004-2008Marie Curie RTN 2004-2008), ), MarbefMarbefMoMAR-FrMoMAR-Fr steering committee set up jointly by steering committee set up jointly byIfremer and CNRS in 2004.Ifremer and CNRS in 2004.

Marine component of EC FP6 Marine component of EC FP6 NERIESNERIES ( (Support forSupport forResearch Infrastructure 2005-2009Research Infrastructure 2005-2009).).

who are the actors so far& what has been achieved ?

MoMAR identified as ISS by US-Ridge, and MoMAR identified as ISS by US-Ridge, and Marine Protected AreasMarine Protected Areas ( (MenezMenezGwen, Lucky Strike and RainbowGwen, Lucky Strike and Rainbow) initiative led by Portugal approved by OSPAR in june) initiative led by Portugal approved by OSPAR in june2007 ..2007 ..


…… first autonomous observatory experiments set up in first autonomous observatory experiments set up in

- 2005: regional Hydrophone Array / serviced in 2006 and 2007, 2 years of- 2005: regional Hydrophone Array / serviced in 2006 and 2007, 2 years ofcontinuous seismicity recording over the entire Azores region (continuous seismicity recording over the entire Azores region (M > 2-3, x-yM > 2-3, x-yrelocation, no zrelocation, no z))

Colonizationboxes

T-probes

CHEMINI

TEMPOpressure gauge

- and 2006 : biologie, vent temperature, geodesy and oceanography at- and 2006 : biologie, vent temperature, geodesy and oceanography atLucky Strike / unfortunately not serviced in 2007 due to ROV problems.Lucky Strike / unfortunately not serviced in 2007 due to ROV problems.Most instruments are still on site, not recording / 1 year of data stored.Most instruments are still on site, not recording / 1 year of data stored.

ocea

nogr

aphi

c moo

ring


@ Ifremer

@ Ifremer

@ Ifremer

@ Ifremer@ Ifremer

BB-OBS (NERIES)

Moored hydrophone

…… ongoing autonomous observatory experiments / regional ongoing autonomous observatory experiments / regional

Example of event recording

regionalregionalHydrophoneHydrophone

Array monitorsArray monitorsseismicityseismicity

2 Broad BandOBSs form acomponent ofthe NERIES

european array

M. Cannat / presentation of Azores Node / ESONET All Regions Workshop Barcelona, sept 5-7 2007@ cnrs/IPGP

@ cnrs/UBO

OBS

pressure gaugebenchmark

…… ongoing autonomous observatory experiments / local ongoing autonomous observatory experiments / local

SeismicSeismicactivity, fluidactivity, fluidcirculationscirculationsand groundand grounddeformationdeformation

@ cnrs/IPGP


@ Ifremer@ Ifremer

ESONET Demo ……..

Please ask me or Ana Colaço, or Pierre Marie Sarradin, or MiguelMiranda, or Ricardo Santos, for further details, web page contacts, PIs

names for the experiments outlined in this talk etc….


Documents

The Azores Node - esonet-noe.org€¦ · hydrothermal vents mine heat over 50 km along-axis ? - Or are they associated with transient magmatic events ? - How do hydrothermal convective