HYDROVOLCANOLOGIE appliquée à la phase hydrothermale

Abstract

L’eau et le feu sont intimement liés depuis la formation du système solaire, il y a 4,5 milliards d’années.
La molécule d’eau participe, sous diverses formes, au magmatisme (plutonisme et volcanisme).
Elle est notamment fondatrice de la phase hydrothermale responsable des évents hydrothermaux sous-marins comme des manifestations paravolcaniques (fumerolles, geyser, solfatares, lacs de cratères...).
La phase hydrothermale reste malheureusement assez méconnue du grand public et les géotouristes
emploient des termes souvent inappropriés pour en désigner les manifestations. Nous proposons,
dans cette rapide synthèse, de préciser les divers termes et d’expliquer la géométrie et la dynamique des systèmes.
Nous en déduisons qu’il s’agit d’un seul et même phénomène dont les manifestations sont différentes.
Nous proposons de retenir la température comme élément discriminant, facilement utilisable,
pour procéder à un arbitrage sémantique et technique au sein des manifestations hydrothermales.

Full text

Hydrovolcanologie : ÉTHIOPIE et DJIBOUTI
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Hydrovolcanologie : NOUVELLE-ZÉLANDE
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
I. Problématique
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II. Hydrovolcanologie
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HYDROVOLCANOLOGIE
appliquée à la phase hydrothermale
&<6;8?-2


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III - Les systèmes hydrothermaux
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Sur la Terre émergée
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68F B5=8GF BAG GBHF 8A 6B@@HA 7gVGE8 6;4H7F
6B@CBFTF 7gHA8 C;4F8 4DH8HF8 :TATE4?8@8AG
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AH86B@@8T?T@8AG7<F6E<@<A4AG
Similarités et différences
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74HGE8 C4EG 7T6;4A:8F
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9?H<78 8G EB6;8 %g8A64<F
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6BA9UE8AG 78F C4EG<6H?4E<GTF CEBCE8F 8G IBAG ?4
E8A7E8C?HF4:E8FF<I88GC?HF6BEEBF<I886894<G
8??8 C4EG<6<C8 Q 78F C;TAB@UA8F 7g4?GTE4G<BAF
466T?TETF78?g8A64<FF4AG8G4668AGH8?8ETF84H78
9<FFHE8F8G789E46GHE8F8AE8@BAG4AGI8EF?4FHE
9468 <8A TI<78@@8AG @V@8 F< ?8 CE<A6<C8
:TATE4?786<E6H?4G<BA;L7EBG;8E@4?8Fg4CC?<DH8Q
GBHF ?8F F<G8F 78F 7<99TE8A68F 8K<FG8AG 74AF ?4
6B@CBF<G<BA78F9?H<78F8G7BA678F7TCZGF
,HE?8C?4A78?46B@CET;8AF<BA?4:TB@TGE<8
7HFLFGU@8<@CBF878F@T?4A:8F7g84H=HITA<?8
8G FBHG8EE4<A8 78F T6;4A:8F ?<DH<78?<DH<78
<@CBEG4AGFCEBI8A4AG7H@4:@4G<F@88GBH7H
IB?64A<F@878FT6;4A:8F9?H<78EB6;86BAF<7T
E45?8FHA:E47<8AG:TBG;8E@<DH8T?8ITE8FCBAF4
5?8 7gT6BH?8@8AGF CB?LC;4F<DH8F :TATE4?8@8AG
GHE5H?8AGF"?Fg8AFH<GGBHG8HA8FTE<878ET46G<BAF
;L7EB:TB6;<@<DH8F 78 6E<FG4??<F4G<BA 8G 78 CET
6<C<G4G<BA 78 @<ATE4HK ABG4@@8AG ?BEF 78F
6;4A:8@8AGF78C;4F8F7BAG?8 C?HF946<?8@8AG
42&.3H8,.:9.0;?@07/0>;=49.4;,@C;=:.0>>@>.3484<@0>/0>HA09?>3D/=:?30=8,@C
/0>=4/0>8H/4::.H,94<@0>P,;=I>,99,>.30? :??78:/414H


%/ '_ '(/&+  F'( F""$(
B5F8EI45?8 8FG ?g4EE<IT8 78F 9?H<78F 8A FHE9468
%8E4CCBEG8AGE8?g84H=HITA<?8CEBI8A4AG7H
7T:4M4:87H@4AG84H8G?g84HFHC8E9<6<8??8E8FG8
7<99<6<?8Q4CCET;8A78EgHA8@4A<UE8:TATE4?8
<?94HG6BAF<7TE8EDH8?4GEUF:E4A78@4=BE<GT78
?g84HN  8FGHA884HFHC8E9<6<8??8E86L6?T8
B@CG8G8AH78?4:TB@TGE<87HFLFGU@8?8F
?46F786E4GUE8C8HI8AGVGE84FF<@<?TFQHAET68C
G46?8CBHE?8FT?T@8AGFIB?4G<?FIT;<6H?TFC4E?8F
9?H<78F;L7EBG;8E@4HK 868 CB<AG78 IH8<?F
E8CETF8AG8AG HA 8AI<EBAA8@8AG 78 6;B<K CBHE
TGH7<8E?g46G<I<GT78?gT7<9<68IB?64A<DH8
IV. Éléments de classification
,< ?8F TI8AGF ;L7EBG;8E@4HK FBHF@4E<AF
FBAG5<8A7T6E<GF<?EU:A8HA868EG4<A86BA9HF<BA
4HF8<A78F@4A<98FG4G<BAFFHC8E9<6<8??8FC4E4IB?
64A<DH8F(AGEBHI874AF?4?<GGTE4GHE87<99TE8AGF
8FF4<F786?4FF<9<64G<BADH<CE8AA8AG8A6B@CG8?4
F<GH4G<BA :TB7LA4@<DH8 ?4 CBA7TE4G<BA 8AGE8
7<99TE8AG8F C;4F8F ?<DH<78 :4M8HF8 78F 4A4
?LF8F <FBGBC<DH8F ?8F 6BAG8KG8F ;L7EB7LA4
@<DH8F ?8F @T?4A:8F 7g84H 8G6 &4?;8HE8HF8
@8AG 68F FLFGU@8F 78 6?4FF<9<64G<BA FBAG GEBC
6B@C?8K8FCBHEVGE8HG<?<F45?8FC4E78FABAFCT
6<4?<FG8F'BHFCEBCBFBAFHA86?4FF<9<64G<BAF<@
C?<9<T8 54FT8 FHE ?4 G8@CTE4GHE8 A CE8@<UE8
4A4?LF8BAL7<FG<A:H8HA8C;4F8Q;4HG8G8@CT
E4GHE8!- FHCTE<8HE8Q  _8G HA8Q54FF8
G8@CTE4GHE8 _
Fumerolles 300 <t<1000 °C
AC4E6BHE4AG?8FG8EE4<AFIB?64A<DH8F<?8FG
9ETDH8AG 78 6EB<F8E 78F MBA8F B] 9<FFHE8F
5BH6;8F 8G TI8AGF 6E46;8AG I4C8HE ;L7EB:UA8
FH?9HET 7<BKL78 78 64E5BA8 8G 4HGE8F :4M 8F
@4A<98FG4G<BAF FBAG :TATE4?8@8AG E8:EBHCT8F
FBHF?8G8E@878b 9H@8EB??8F c%8HEG8@CTE4GHE8
C8HG I4E<8E 78  Q   _ FHE 78F IB?64AF
46G<9F%4 I<G8FF878F:4M C8HGVGE8FHCTE<8HE8Q
 @Ff TATE4?8@8AG ?8F T@<FF<BAF A8
6BAG<8AA8AGC?HF78:4MGEUF4:E8FF<9F!!? 
@4<F7H,(C8HGVGE8CETF8AG8A:E4A78DH4A
G<GT74AF68EG4<A8F9H@8EB??8F6B@@84H$4J4;
"=8A#4I4"A7BATF<88G4H<?<E4A);<?<CC<A8F
%8FIB?H@8F:4M8HKC8HI8AG4GG8<A7E8C?HF<8HEF
@<??<4E7F78@UGE8F6H58F
%8F 9H@8EB??8F 6BEE8FCBA78AG @4=BE<G4<E8
@8AGQ78FT@<FF<BAF:4M8HF8F??8F466B@C4
:A8AG:TATE4?8@8AG?8FTEHCG<BAFIB?64A<DH8F8G
C8EF<FG8AG4FF8M?BA:G8@CF4CEUF?gTEHCG<BA(A
C8HG7<FG<A:H8E78HKGLC8F789H@8EB??8F 
f FU6;88AGE8 _8G  _E<6;8F8A!
,(8G?
f 46<78F 8AGE8  _ 8G  _ E<6;8F 8A
!((!,(!,8G!?
%BEFDH8 ?4 G8@CTE4GHE8 78F 9H@8EB??8F 78F
68A78A78FFBHF78 _?8FFH?94G8FCET7B@<
A8AG8GC4E@<?8F6;?BEHE8F4CC4E4<FF8AG?86;?B
EHE87g4?H@<A<H@??8G?86;?BEHE898EE<DH8
8? 8 78EA<8E 6B@5<AT Q ?g84H F8 GE4AF
9BE@88AB?<:<FG88(DH<F87TCBF874AF?8F
9<FFHE8FFBHF?49BE@8786E<FG4HKG45H?4<E8FAB<EF
8G5E<??4AGF946<?8@8AGE86BAA4<FF45?8F
)?HF ?g46G<I<GT @4:@4G<DH8 FBHF=468AG8 8FG
<@CBEG4AG8C?HF ?4 G8@CTE4GHE8 78F9H@8EB??8F
4H:@8AG8 4<AF< DH8 ?8HE 46<7<GT 8G ?8 IB?H@8
7gT@<FF<BA 78 6B@CBFTF FBH9ETF %46G<I<GT
9H@8EB??<8AA8 8FG HA <A7<64G8HE C8E@8GG4AG 78
CETIB<E78CBG8AG<8??8FTEHCG<BAFIB?64A<DH8F
H=BHE7g;H<?8G8E@89H@8EB??88FG4FF8M:4?
I4H7T8G7TF<:A8<A7<FG<A6G8@8AGGBHG8@4A<98F
G4G<BA:4M8HF8T@<F8C4EHAFLFGU@8;L7EBG;8E
@4?"?94HG68C8A74AGA8C4F?8F6BA9BA7E84I86
?8FFB?94G4E8F
Solfatares 100 <t<300 °C
%8G8E@8<G4?<8A>:71,?,=, ?<GGTE4?8@8AG b G8EE8
78FBH9E8FBH9E<UE8 c7TF<:A4<GQ?gBE<:<A8HAIB?
64A F<GHT 74AF ?8F ;4@CF );?T:ET8AF 8AGE8
)BHMMB?8F8G'4C?8F"G4?<86BAAHCBHE6E46;8E
78 ?4 I4C8HE FH?9HE8HF8 %4 F<:A<9<64G<BA 78 68
@BG48AFH<G8TGTTG8A7H8QGBHF?8FG8EE4<AF7gB]
F87T:4:8AG78?4I4C8HE7g84H8G78F6B@CBFTF
FBH9ETF%8F FB?94G4E8FFBAG 6B@CBFT8FQ  
7g84H FBHF 9BE@8 I4C8HE 8G 78F 6B@CBF4AGF
I4E<TF (!'!!,"?8FFBAG:TATE4
?8@8AG 8AGBHET8F 78 7TCZGF 78 FBH9E8 CEB7H<G
?BEFDH8?g;L7EB:UA8FH?9HET8AGE88A6BAG46G4I86
?g4<E8GET4:<G4I86?gBKL:UA8AC?HF78F6B@CB
FTFFBH9ETF8K<FG8AGT:4?8@8AG78FFH?94G8F4?H
A<G8 A4GEB4?HA<G8 =4EBF<G8 :LCF8 8G DH8?DH8F
6B@CBFTF 9H:468F 78 FH?94G8F ;L7E4GTF (A
GEBHI8 4HFF< 78F 4E:<?8F >4B?<AF ABG4@@8AG
8F F@86G<G8F C8HI8AG F8 9BE@8E ?BEFDH8 ?8F
46<78FFBAGA8HGE4?<FTF8F7<I8EF7TCZGF6BA9U
E8AG4HKFB?94G4E8F78@4:A<9<DH8FG8<AG8F=4HA8F
B6E8EBH:8F%478F6E<CG<BAF8E4<G<A6B@C?UG8F<
?gBA A8 @8AG<BAA4<G C4F ?8F 5EH<GF <ADH<TG4AGF
94F6<A4AGF 8G ?gB78HE A4HFT45BA78 78F 6;4@CF
FB?94G4E<8AFDH<E4CC8??868??878 ?geH9 CBHEE<
%g4G@BFC;UE8L8FG F< C4EG<6H?<UE8 DHg<?FTG4<8AG
=47<F 4FF<@<?TF 4HK CBEG8F 78 ?g8A98E 8 DH<
64E46GTE<F8?8FFB?94G4E8F6g8FG?4CETF8A68F<@H?
G4AT87gHA8C;4F8?<DH<787gHA8C;4F8:4M8HF8
78CEB7H<GF7g4?GTE4G<BA4E:<?8F8G?4CETF8A6878
FBH9E88EG4<A8FFB?94G4E8FBAGTGT8KC?B<GT8F78
@4A<UE8<A7HFGE<8??8CBHE8KGE4<E87HFBH9E8
H @<?<8H 78F 6;4@CF FB?94G4E<8AF BA
B5F8EI8 C4E9B<F 78F @4E8F 78 5BH8 5BH<??BA
A4AG8F 9H@4AG8F 8G @4?B7BE4AG8F 8F b @4E
@<G8F 785BH8 c 8@/;:?> F8 9BE@8AG :TATE4?8
@8AG74AF?8FFB?94G4E8FB]?g84H8FG45BA74AG8
.A868EG4<A8 6BA9HF<BA 8K<FG8 DH4AG Q F4IB<E F< ?8 G8E@88FG
@4F6H?<A)8G<G+B58EGBH9T@<A<A)8G<G%4EBHFF8'BHFE8G<8A
7EBAFDH8?8G8E@8CEBI<8AG78>:71,?,=, 8A<G4?<8ADH<8FG9T@<A<A


&"!% -2 +%")"!""
ACEB9BA78HE?g84H6;4H99T846<7<9<T87<FFBHG
?8FEB6;8F4?8AGBHE%g4E:<?89BE@T8 F8@T?4A:8
4I86?g84H8G7BAA8HA85BH8C?HFBH@B<AFI<F
DH8HF8F8?BA?8FDH4AG<GTFE8?4G<I8F7g84H8G7g4E
:<?8F ,BHI8AG 78F 5H??8F 78 :4M 64E5BA<DH8
E8@BAG8AG8G T6?4G8AGQ ?4 FHE9468 %45BH8 8FG
E8=8GT8 FHE ?8F 5BE7F 78 ?4 @4E8 8G Fg466H@H?8
9BE@4AG C4E9B<F HA ITE<G45?8 C8G<G 6E4GUE8 CBH
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74AFHAC8G<GAB@5E878F<G8FQGE4I8EF?8@BA78
7BAG?8FC?HF<@CBEG4AGFF8GEBHI8AG4HKOG4GF
.A<F8A+HFF<88A'BHI8??83T?4A784H;<?<8G
8A"F?4A78
%8C4E6A4G<BA4?78+077:B>?:90 OG4GF.A<F8A
45E<G8Q?H<F8H?GEB<F68AGFFB<GCEUF78?4@B<G<T
78F:8LF8EFCETF8AGFFHE -8EE8g8FG T:4?8@8AG
?Q DH8 ?gBA GEBHI8 ?8 C?HF ;4HG 78 GBHF ?8
&?0,8-:,? ,8F =4<??<FF8@8AGF 4GG8<:A8AG  @ 8G
7HE8AG8AGE8 8G @<AHG8F@4<F 8??8FE8FG8AG
<@CETI<F<5?8F8G?g<AG8EI4??88AGE878HKTEHCG<BAF
C8HG4??8E78 DH8?DH8F=BHEFQ C?HF<8HEF4AAT8F
%8F GBHE<FG8F ?H< CET9UE8AG 7BA6 ?g"7/ ,4?31@7
0D>0= 7BAG?8F=4<??<FF8@8AGFFBAGC?HFET:H?<8EF
GBHG8F?8F @<AHG8F8AI<EBA5<8ADH8@B<AF
<@CE8FF<BAA4AG8F8AGE88G @UGE8F
%4 I4??T8 78F :8LF8EF 74AF ?4 CTA<AFH?8 7H
$4@G6;4G>4 ,<5TE<8 +HFF<8 45E<G4<G CEUF 78
68AG:8LF8EF4I4AGDHgHA:?<FF8@8AG78G8EE4<A78
 @<??<BAF78@UGE8F6H58F8AAg8AE4L8
C?HF78?4@B<G<T78?464EG8%4C?HC4EG78F:8L
F8EF7<FC4EHFTG4<8AGHA<DH8F78C4E?8HEFTEHC
G<BAF B5?<DH8F !8HE8HF8@8AG ?8 :8LF8E
N )0646,9 O ?8 :T4AG 7BAG ?8F TEHCG<BAF
4GG8<:A<E8AG  @ 4 FHEIT6H 4H :?<FF8@8AG 78
G8EE4<A
Lacs acides et lacs de cratère : t<100 °C
%8 64G4?B:H8 78F IB?64AF 46G<9F 7H &BA78
6BAF<7UE8 DH8   78F  IB?64AF 46G<9F 78
?g!B?B6UA8   4AF CBFFU78AG HA ?46 78
6E4GUE8 8?4 7BAA8 HA BE7E8 78 :E4A78HE
F46;4AGDH8?8F?46FIB?64A<DH8FA8F8F<GH8AGC4F
HA<DH8@8AG74AF78F6E4GUE8FFB@@<G4HK8GDH8
?47LA4@<DH87HIB?64A<F@88FGG8??8DH868F?46F
BAGHA88K<FG8A68TC;T@UE8-BHG8CBF<G<BA:TB
@BEC;B?B:<DH86BA9BA7H8BA8FG<@8?8AB@5E8
78?46F46<78F8A94<GQ<8ADH8?8HEETC4E
G<G<BAFB<G@BA7<4?8BA?8FE8A6BAGE8@4=BE<G4<
E8@8AG4FFB6<TF 4H IB?64A<F@87g4E6%8F C4E4
@UGE8FC;LF<6B6;<@<DH8F7868F?46FFBAG8KGEV
@8@8AGI4E<45?8F64E<?FFBAG?8E89?8G78?g46G<
I<GT;L7EBG;8E@4?88G@4:@4G<DH8FBHF=468AG8
)BHEVGE874AFHATG4GE8?4G<I8@8AGFG45?874AF?8
G8@CF 68F ?46F 78@4A78AG 78F 4CCBEGF 8A 84H
6BAFG4AGF 78F 58E:8F <@C8E@T45?8F HA 9?HK
:TBG;8E@<DH8 8G HA 4CCBEG F<:A<9<64G<9  8A T?T
@8AGF IB?4G<?F 8GG8 7LA4@<DH8 8FG 9ETDH8AG8
FHE?8FIB?64AF46G<9FB]?87T:4M4:88FG<@CBE
G4AG%8 ?4678 6E4GUE8F8 6B@CBEG8 6B@@8HA
:E4A7ET46G8HEB]7<99TE8AG8FET46G<BAFC;LF<6B
6;<@<DH8F8G5<B?B:<DH8F6B@C?8K8FIBAGBCT
E8E8AC4E4??U?8(AE8A6BAGE878F ?46F 74AF?8F
6E4GUE8F@4<F4HFF<74AF78F64?78<E47g899BA7E8
@8AG8G74AF 78F 6E4GUE8F?4GTE4HKCEB7H<GF 7H
C;ET4GB@4:@4G<F@8DH<C8HI8AG6BAFG<GH8E78F
%/ '_ '(/&+  F'( F""$(

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@44EF (A 8A GEBHI8 ABG4@@8AG 8A HI8E:A8
74AF?4 6;4XA8 78F )HLF8A ??8@4:A8 74AF?8
@4FF<978?g<98?BH8A6BE88A"F?4A78
4AF ?8F ET:<BAF G86GBA<DH8@8AG 46G<I8F
6B@@8 ?8 E<9G 8FG49E<64<A 8G ?8F MBA8F IB?64
A<DH8F 6B@@8 ?8 28??BJFGBA8 ?8F 6<E6H?4G<BAF
;L7EBG;8E@4?8F C8HI8AG 4CCBEG8E 78F F8?F 7<F
FBHF DH< @B7<9<8AG F8AF<5?8@8AG ?4 6;<@<8 78F
?46Fg8FGABG4@@8AG?864F 7H?46$<IH8G 7H
?46?58EG7BAG?4G8A8HE8A&: $8G?fF8
GEBHI8AG VGE8 I<A:G 9B<F C?HF T?8IT8F DH8 ?8F
6BA68AGE4G<BAF 7H ?46 /<6GBE<4 IB<F<A 8F
6BA68AGE4G<BAFb 4ABE@4?8F cFBAG?4F<:A4GHE878
?4 CETF8A68 7H E<9G 8FG49E<64<A 8G 7g4CCBEGF
;L7EBG;8E@4HKCEB9BA7F
%g84H7H?46CEB6U78GBH=BHEF 7gHA@T?4A:8
7g84H 7BAG ?4 @4=BE<GT CEBI<8AG 78F CET6<C<G4
G<BAF8G7g84HFBHG8EE4<A8%46B@CBF4AG88A84H
=HITA<?8 8FG :TATE4?8@8AG 94<5?8 8 @T?4A:8
7g84H4TGTDH4AG<9<T8A'BHI8??83T?4A78B]?4
6B@CBF<G<BA7H?46-4HCB@8G8ATI<78A6878F
4CCBEGF;L7EBG;8E@4HKCEB9BA7FFBHF?46HFGE8F
DH<F8E4<8AGE8FCBAF45?8F78 7H,<( 
78'!8G 78'4?8@V@8?8?46)BPF
4HBFG4 +<64 BH?8 ?46 +H4C8;H8A 'BHI8??8
3T?4A78@BAGE8AG78F@T?4A:8F7g84HCEB9BA78
8GFHC8E9<6<8??8
%8F?46F786E4GUE8IB?64A<DH8F46G<9FCETF8A
G8AG78F6B@CBF<G<BAF6;<@<DH8F8KGEV@8F??8F
FBAG:TATE4?8@8AG 64E46GTE<FT8FC4E HA C! 94<
5?8 GEUF 46<78 8G 78F 6BA68AGE4G<BAF 8A ?f
,(fGEUFT?8IT8FC8E@8GG4AG?4@<F88AFB?HG<BA
78@TG4HK8&A?"?FC8HI8AGVGE86BAF<7T
ETF6B@@8?8FG478<A<G<4?78?4A8HGE4?<F4G<BA78F
46<78F@<ATE4HKIB?4G<?FCEBI8A4AG7H7T:4M4:8
7H@4:@4 CEB7H<F4AG 78F <BAF 8G78F CEB7H<GF
7g4?GTE4G<BA
HF8<A7868F?46F!8FG?864G<BA7B@<A4AG
7UF DH8 ?8 C!  C4E 8K8@C?8  )<A4GH5B 4HK
);<?<CC<A8F C!   $4G4AH@4 4H #4CBA
C!  )BPF4HBFG4+<64C!  $4J4;
"=8AQ#4I4C! 878EA<8EE8A98E@8?8?46
6BAF<7TET 6B@@8 ?8 C?HF 46<78 6BAAH 7gHA
IB?H@878Q  &@F<GHT Q  @ 7g4?G<
GH78
%8F ?46F 78 6E4GUE8F 46G<9F E8CETF8AG8AG HA
E<FDH8 IB?64A<DH8 FHCC?T@8AG4<E8 8A FHE<@CB
F4AG4HE<FDH87gTEHCG<BAHA86B@CBF4AG8?4;4E
BH=[>H?;?4HC
Les lacs à forte teneur en CO2: t<100 °C
.A4HGE88998G7HIB?64A<F@88FG78CEB7H<E8
7H :4M 64E5BA<DH8 8A DH4AG<GT <@CBEG4AG8 8
:4MC8HGF8@T?4A:8EQ?g84H=HFDHgQ4GG8<A7E878F
6BA68AGE4G<BAF 8KGEV@8F FHF68CG<5?8F 7gVGE8
E8?4E:HT8F5EHG4?8@8AG
8F?46F46<78F78FIB?64AF46G<9FFBAG:TATE4
?8@8AGGEBC46<78FCBHE6BAF8EI8E?8(FBHF
9BE@8 7g<BA 5<64E5BA4G8 !( Q ?g8K68CG<BA
78F ?46F 'LBF 8G &BABHA 4@8EBHA B] ?8F
T@<FF<BAF 78 :4M 46<78F BAG 68FFT ,( !,
!?94<F4AG7868F?46FHAETF8EIB<EQFH?94G8F8G
6;?BEHE8F @4<F FHEGBHG Q (7<FFBHF 8
6B@CBFTQ?gTG4G7<FFBHF74AF?8?468FGFHF68CG<
5?878C4FF8EQ?gTG4G:4M8HK6B@@88A4GG8FG8AG
?8F TEHCG<BAF ?<@A<DH8F 78F ?46F 64@8EBHA4<F
'LBFN &@78(f @BEGF8A
8G &BABHA N &@78 (f  @BEGF 8A
 ,H<G8 Q 68F TITA8@8AGF 64G4FGEBC;<DH8F
68F78HK?46FFBAG@4<AG8A4AGTDH<CTF787<FCB
F<G<9F78@T64A<F@8F4EG<9<6<8?F787T:4M4:8F
%8 ?46 $<IH F<GHT 8A +TCH5?<DH8 T@B6E4
G<DH87HBA:B+ Q  @7g4?G<GH788FG
?8C?HFC8G<G78F E4A7F%46F49E<64<AFFBH?<:A4AG
?8GE46T7HE<9G8FG49E<64<A%8FE8?4E:4:8FB5F8E
ITF74AF?8?46$<IH?BEF78?gTC<FB78TEHCG<9 7H
'L<E4:BA:B8ABAG4?8EGT?8FF6<8AG<9<DH8F
FHE?8E<FDH87gTEHCG<BA?<@A<DH8A8998G68?46
4 ?4 64E46GTE<FG<DH8 78 E8A98E@8E 78 :E4A78F
DH4AG<GTF78 :4M7<FFBHF (8G! FGE4G<9<T
74AF?8FCEB9BA78HEF7H?46CEUF?gTEHCG<BA7H
'L<E4:BA:B8A78F<AI8FG<:4G<BAFBAGC8E
@<F 78 DH4AG<9<8E ?4 G4<??8 78F ETF8EIB<EF Q
 >@FB<G  &@ 78 :4M 64E5BA<DH8
8G >@78 @TG;4A8 DH4AG<9<TFQ  _8G HA8
4G@BFC;UE8%8F64G4FGEBC;8F;H@4A<G4<E8FDH<
A8@4ADH8EBAGC4F78F8CEB7H<E8FBH?<:A8AG?8
E<FDH8 DH8 E8CETF8AG8 ?8 ?46 $<IH F46;4AG
DHg8AGE8 >@8G &@<?L4HA946G8HE78
6g8FGQ7<E8 DH8 ?gBA C4E?8 78  @<??<4E7F 78
@UGE8F6H58F78(CBHE?8?46$<IH)BHE9<K8E
?8F<7T8F6;4DH8?<GE87g84H7H?46$<IHE8A98E@8
78HK?<GE8F78:4M78@TG;4A88G78:4M
64E5BA<DH8 FB<G   9B<F C?HF 78 :4M DHgQ
'LBF FG<?HG<?8 78E4CC8?8EDH8 ?8:4M 64E5B
A<DH8 C?HF ?BHE7 DH8 ?g4<E 8FG <A6B?BE8 8G <AB
7BE8 ,4 GBK<6<GT6B@@8A68Q  ,4 CETF8A68
Q   8AGE4XA8 HA8 C8EG8 5EHG4?8 78 6BAA4<F
F4A68  Q  <? CEBIBDH8 HA 4EEVG E8FC<E4GB<E8
DH<8AGE4XA8?87T6UF8@V@8?8@TG;4A88FG
<A6B?BE88G<AB7BE8"?C8HG6B@@8?8(CEB
IBDH8E 78F 4FC;LK<8F 8A CE8A4AG ?4 C?468 78
?BKL:UA8 74AF ?4<E "? 8FG C4E 4<??8HEF 8KGEV@8
@8AG<A9?4@@45?8
"?F8@5?8DH8?8(FB<GCEB7H<GC4E?g46G<I<GT
IB?64A<DH84?BEFDH8?8!8FGCEB7H<GC4E78HK
CEB68FFHF  ?4ET7H6G<BA 78(@4<F4HFF< C4E
?gBKL74G<BA78?4@4G<UE8BE:4A<DH8C4E46G<I<GTF
546GTE<8AA8F%8CE8@<8ECEB68FFHF6BAGE<5H84H
8G?8F86BA74H78?4DH4AG<GTGBG4?878
@TG;4A89BE@T 74AF?8?46 $<IH8CH<F
BA4B5F8EITHA84H:@8AG4G<BA<A4GG8A7H878?4
6BA68AGE4G<BA 78 @TG;4A8 7g8AI<EBA  Q
  .A8 G8??8 6BA68AGE4G<BA 4CCEB6;8 ?8
A<I84H78F4GHE4G<BA78 ?g84H4H78?Q 7HDH8? ?8
E<FDH87g8KC?BF<BA ?<@A<DH8 78I<8AGHA8 ITE<G4
&"!% -2 +%")"!""


%/ '_ '(/&+  F'( F""$(
5?8 @8A468 CBHE ?8F CBCH?4G<BAF E<I8E4<A8F
 B@48GH>4IH8A+8GL4A:H:H <F8A:<
8G$<5HL84H+J4A74FB<G8AI<EBA78HK@<??<BAF
78C8EFBAA8F%8FTI8AGH8?F7T:RGF6BAFT6HG<9FQ
HA87T:4M4:8FH<I<7gHA88KC?BF<BA?<T8Q?4CET
F8A6878@TG;4A8F8E4<8AG7BA66BAF<7TE45?8F
%8 ?46 -44? 4HK );<?<CC<A8F 7<FCBF8 T:4?8
@8AG78:E4A78FDH4AG<GTF78(7<FFBHF8GHA8
TEHCG<BA ?<@A<DH8 8FG CEB545?8 %8 ?46 B66HC8
HA8 ?4E:8 64?78<E4 78  >@ C4E  >@ %8
IB?H@87H?46786E4GUE88FG78 ?gBE7E8 78Q
 &@C!78GN_AI<EBA  C8E
FBAA8F I<I8AG Q CEBK<@<GT <@@T7<4G8 7H ?46
AGE89TIE<8E 8G @4EF  ?4DH4AG<GT 7gT@<F
F<BA78:4M64E5BA<DH88FGC4FFT878  G=Q
  G= ?4<FF4AG C8AF8E Q ?4 CEBK<@<GT 7gHA8
TEHCG<BA ?<@A<DH8 %8 #3474;;490 9>?4?@?0 :1
):7.,9:7:2D ,9/ &04>8:7:2D )!"/(%, 4I4<G
4?BEFCBEGT?8A<I84H7g4?8EG8Q4AF?4@8FHE8
B] ?4 G8@CTE4GHE8 78 ?g84H 7H ?46 Ag4 C4F 4H:
@8AGT BA C8AF8 DH8 ?g4H:@8AG4G<BA 78 (
AgTG4<GC4F?<T8QHA8CBFF<5?8TEHCG<BA?<@A<DH8
@4<FQ?4E8@BAGT878:4MIB?64A<DH8F
%8?46786E4GUE87H$8?H7"A7BATF<8<??HFGE8
T:4?8@8AG?8E<FDH8787T:4M4:878(8?46
8FG?B64?<FT74AFHA8MBA878#4I4Q9BEG8CBCH
?4G<BA 4I86 GEB<F @<??<BAF 7g"A7BATF<8AF DH<
I<I8AG Q CEBK<@<GT 7H ?46 %8 IB?64A 4 8H 4H
@B<AFGE8AG8TEHCG<BAF;<FGBE<DH8FETC8EGBE<T8F
94<F4AG   @BEGF 78CH<F    ?4 78E
A<UE84L4AG8H?<8H8A9TIE<8E
Proposition de classification des lacs
de cratère
%"/" 9?0=9,?4:9,7 >>:.4,?4:9 :1 ):7.,
9:7:2D,9/3084>?=D:1 ?30,=?3>9?0=4:= 4@<F8A
C?468HA8 6B@@<FF<BACBHE ?gTGH7878F ?46F78
6E4GUE8??8E8:EBHC8FBHF ?8 G8E@8?46 786E4
GUE8 GBHF ?8F ?46F IB?64A<DH8F DHg<?F FB<8AG 78
6E4GUE8BH78@44EA9BA6G<BA78?46BA68AGE4
G<BA8A 4A<BAF 78F84HK ?4 6B@@<FF<BA4 CEB
CBFT786?4FF8E?8F?46F786E4GUE8 8AGEB<F64GT
:BE<8F E8CETF8AG4AGF 7<99TE8AGF FG478F 78
@4GHE<GT142 
f ?8F ?46F 78 GLC8 46<78 FH?94G8  6;?BEHE8
,  8K ?8 $4J4; "=8A "A7BATF<8 BH ?4
?4:HA44?<8AG87H)BPF4HBFG4+<64"?FETFH?
G8E4<8AG7gHA@T?4A:8<@CBEG4AG78:4M7gBE<:<A8
@4:@4G<DH8,(!,!?8G!8GBAGHAC!
GEUF46<788AGE88G%46BA68AGE4G<BA8A,(
8FGQ?gBE<:<A8787TCZGF78FBH9E8FB?94G4E8F8G
7g46<78FH?9HE<DH8!,(%46BA68AGE4G<BA8A
FH?94G8FC8HG4GG8<A7E8  CC@4I86HA-,
CBHI4AG4GG8<A7E8 :>:f 
f ?8F?46F78GLC8A8HGE86;?BE HE8' 8K?8
?467H*H<?BGB4 8G ?8$8?H7"?FFBAG ?8ETFH?G4G
7gHA TDH<?<5E8 4I86 ?4 EB6;8 8A64<FF4AG8 B]
?46<7<GT4TGTA8HGE4?<FT8
f ?8F ?46F 78 GLC8 A8HGE8 5<64E5BA4G8 ' 
6B@@8?8F?46F 'LBF8G&BABHA 8F?46F BAG
C8E7H?8HE46<7<GT8GFBAG7TCBHEIHF78FH?94G8F
8G78 6;?BEHE8F @4<F 6BAG<8AA8AGHA8 DH4AG<GT
<@CBEG4AG878(7<FFBHF
Les lacs salés : t<100 °C
%8F?46FF4?TFE8CETF8AG8AGHA64F<AGTE8FF4AG
B] C?HF<8HEF CEB68FFHF :TB6;<@<DH8F FBAG FHF
68CG<5?8F78Fg8KCE<@8EgHA8@4A<UE8:TATE4?8
?BEFDHg<?AgL4C4F7g8KHGB<E84TE<8ABHFBHG8EE4<A
?46F 8A7BET<DH8F BH G8E@<A4HK ?4 GBG4?<GT 78
?g84HE8SH8FgTI4CBE868DH<6BA7H<GQHA8@<AT
E4?<F4G<BA @4EDHT8 BAI8AG<BAA8??8@8AG BA
6BAF<7UE8 DHgHA ?46 8FG F4?T ?BEFDH8 ?8F F8?F
GBG4HK 7<FFBHF 8K6U78AG  :? *H4A7 ?4 ?4@8
7g84HE8SH88FGFH99<F4AG8CBHEDH8?8?46A8Fg4F
FU6;8 C4F HA TDH<?<5E8 F4?<A Fg<AFG4HE8 "? 8FG
64E46GTE<FT C4E HA8 ATB:8AUF8 74AF ?8F FT7<
@8AGFCET6<C<G4G<BA78F64E5BA4G8FCH<F78FFH?
94G8F8G8A9<A78F;4?B:TAHE8F?BEFDH8 ?8F84HK
7TC4FF8AG  :? FB74 ?4>8 7H 6E4GUE8 ;8J
8G 8A G;<BC<8  ?46 FF4? 8A +TCH5?<DH8 78
=<5BHG< %BEFDH8 ?gTI4CBE4G<BA 8FG FHCTE<8HE8
4HK4CCBEGF?8?46Fg4FFU6;88G<?L4CET6<C<G4G<BA
DH4F< GBG4?8 78F F8?F 7<FFBHF 6g8FG ?8 CEB68FFHF
78FF4?<A8FBH>,7,= .LHA<74AF?g?G<C?4AB5B?<
I<8AC4E8K8@C?8
%8?46FF4?=<5BHG<Fg8FGE8GEBHIT<FB?T78
?4@8E?BEF78?4@<F88AC?4687HFLFGU@8IB?64
A<DH8 78 ?gE7BH>Z54 "? 6BAG<AH8 7gVGE8 4?<
@8AGT8A 84H C4EHA 9?HK FBHG8EE4<A 8A CEBI8
A4A687H :B?98 78 -47=BHE4C4E ?g<AG8E@T7<4<E8
78 ;BH558G ? $;4ER5 %8 9?HK 74AF FBA
IBL4:8FBHG8EE4<A74AF?g4K87HE<9G8FG8AE<6;<
C4E?8F9?H<78F;L7EBG;8E@4HK8GGE4AF9BE@T8A
F4H@HE8F"?FH5<G74AF?8?46FF4?HA8TI4CB
E4G<BAGEUF9BEG88FG<@T8Q &@4ADH<C4E
G<6<C8 Q ?4 6BA68AGE4G<BA 78 ?4 F4H@HE8 %gTI4
CBE4G<BA TG4AG ?T:UE8@8AG FHCTE<8HE8 4HK
4CCBEGF?8?46F8F<GH84H=BHE7g;H<Q@B<AF @
C4EE4CCBEG4HA<I84H78?4@8Eg8FG?8CB<AG?8
C?HF54F7H6BAG<A8AG49E<64<A
8EG4<AF7TCZGFF4?TFFBAG9BA74@8AG4?8@8AG
FBHF ?g<A9?H8A68 7H E<9G 8G 78F C;TAB@UA8F
;L7EBG;8E@4HK4?BEFDH87g4HGE8FC8HI8AG4IB<E
78FBE<:<A8F7<I8EF8F6L6?8CET6<C<G4G<BAFTI4CB
E4G<BAABG4@@8AG
Mofettes et sources thermominérales :
t<50 °C
%8F@B98GG8F FBAG 64E46GTE<FT8FC4E ?8 7T:4
M4:8 78 (:TATE4?8@8AG Q G8@CTE4GHE8
4@5<4AG88FBAG78F@4A<98FG4G<BAFG8E@<A4?8F
7HIB?64A<F@8%4C?HF6BAAH88FG?4:EBGG8 7H
6;<8A Q :A4AB 8A "G4?<8 EBGG8 B] F8?BA ?4
dA8C4F6BA9BA7E84I86?8?46FF4?88AOG;<BC<874AF
?47TCE8FF<BA4A4><?


427,>>414.,?4:9/0>7,.>A:7.,94<@0>091:9.?4:9/07,.:9.09?=,?4:909,94:9>'D;0,.4/0>@71,?0.37:=@=0&90@?=0.37:
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Les eaux encroûtantes : t<50 °C
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V - Un monde habité par les
extrêmophiles
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VI - Conclusion
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Orientation bibliographique
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