Diapositive 1

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France s SALE activities Update and future
plans J.R Petit , LGGE Grenoble, France
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• Science one going studies on Vostok accretion
  ice
• Searching life in ice
• collaborations with Russians (PNPI, AARI) Frame
  of GDRE (CNRS-RAS) (extended to glacier ice and
  drilling fluid)
• Tripartite project (NSF-IPEV-RAE) on going (2
  increments 1M long ice core under studies, 3613,
  3621m) collaboration (PNPI, Univ Bowling Green)
• Replication and search for specific genes
  (chemoautotrophic, hydrogenase) (Univ Lyon,
  Laboratoire dEcologie Microbienne, P Normand, C
  Lavire)
• Ice geochemistry
• Water isotope (D, 18O) composition (AARI, CEA
  Saclay, F )
• Helium in ice (CEA Saclay,F, P Jean Baptiste)
• Inclusion studies (synchrotron radiation) and
  chemistry (LGGE)
• Ice chemistry and Organic acids (Formic, acetic,
  oxalic) and DOC measurements (collaboration Univ
  Heidelberg)

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Searching biological fingerprints in deep ice
cores -Constraints - ice is very clean
(contains 1/1000 total salts wrt spring water)
-very low biomass -outer part of ice core is
contaminated -Technical prerequisites -Clean
room dedicated to ice core analysis -decontaminat
ion steps -low DOC pure water system used as
blank reference and final rinsing -use
geochemistry for validation of first steps of
preparation -Guiding principles for searching
ancient DNA -separated labs -comparing
potential contaminant to signal -independent
replication
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Vostok
NW
4He
SE
3m/a
10 40
0 m
Glacier ice
N
11 Km
45 Km
NW
SE
3538m
4He
Accretion ice 1
3608m
3623m
4He
Accretion ice 2
4He
Deep lake
 600m
3750 m
Bulat et al, 2004
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3He/4He
4He
Atmospheric ratio
As deduced from Jean Baptiste et al, 2001
(A seismo-tectonic environment)
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• Geologic and geochemistry arguments support an
  hydrothermal environment in Lake Vostok and
  molecular biological print of thermophilic
  bacteria niches within bedrock (Bulat et al,
  2004)
• setting of the lake, faults are present
• earthquakes detected (Studinger et al, 2003) and
  they could explain brine inclusions within
  accretion ice (i.e. seismo tectonic environment)
• excess of helium (4He) suggesting fault degassing
  (in shallow bay?)
• isotope composition of ice enriched in 18O w.r.t
  the lake water supply

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D deuterium excess of precipitations d dD
-8d18O
d 11
d 8
d 14
165 km
Melting area is downstream Dome B (mean d 11
) One would expect d 11 for accretion ice in
case of equilibrium of lake balance (Souchez et
al, 2003)
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Accrétion dD-442.5
Melting ice
Accretion ice d 7
Vostok d 14
Dome B dmin11
Dd18O 0.5
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dD versus d18O defines the Meteoric Water Line
(MWL) with a slope of 8 Isotope composition of
water in geothermal areas (oil fields,
volcanoes,)enriched in 18O due to exchanges with
rocks at high temperature From Craig, 1966,
Criss et al, 1968)
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Replication of findings Drilling
fluid analysis Alekhina et al, FEM, 2007
(more at this meeting).
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Field operations -Support RAE for logistic
(52 RAE), IPEV (proposal Glaciolac) Participation
of one French to the 2006-7 Vostok summer field
season -Objectives sampling of new drilled
accretion ice for gases -ice biology and
geochemistry -helium (3He/4He) -hydrogen (from
rock-water interaction through tectonic) -Operati
ons 8 m ice core drilled (3650-3658m) 10
Helium samples collected , Two samples for
hydrogen analysis . Gas samples delivered at
LGGGE (end of April 2007) for measurements
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• Future plansSALE-Related funded /submitted
  proposal
• Astrolabe emissary glacier (Dacota leaded by E
  Lemeur, LGGE )
• funded
• Ice dynamics and response of to recent
  accumulation (labeled IPY).
• Aero-geophysical survey for bed rock
  (collaboration with BAS/Uni Milano/NASA JPL/..)
• Lake Vostok studies (lab studies cont)
• submitted
• with extension to temperate glaciers
• LGGE, UNI Lyon, Uni Brest, CEA Saclay with
  collaboration with PNPI
• VANISH (TASTE idea) M Fily (LGGE)
• submitted
• Talos Dome DomeC Vostok Dome A- Dome B
  Komsomolskaya-Dome C)
• Include surface radar (accumulation), shallow
  cores (isotope samplings),
• in collaboration with Italians and Russians.