Lake Pavin History, geology, biogeochemistry, and sedimentology of a deep meromictic maar lake

396

0

0

9 8 7 6 5 4 3 2 1

10 20 30 40 50 60 70 80

L* (%)

700/40

0

A

B

C

F

E

D

0

0

9 8 7 6 5 4 3 2 1

10 20 30 40 50 60 70 80

L* (%)

700/400

A

B

C

F

E

D

0

0

9 8 7 6 5 4 3 2 1

10 20 30 40 50 60 70 80

L* (%)

700/40

0

A

B

C

F

E

D

Total Organic Carbon (%)

0

50

100

150

200

0 5 10 15 20 25 30

S2

(m

gHC/

g rock

)

HI = 750 mgHC.g

-1 TOC

HI = 300 mgHC.g

-1 TOC

0

50

100

150

200

0 5 10 15 20 25 30

Total Organic Carbon (%)

HI = 750 mgHC.g

-1 TOC

HI = 300 mgHC.g

-1 TOC

Littoral deposit

Diatomite

S^2

(m

gH

C/g

rock

)

50

100

150

200

S^2

(mgH

C/

g rock

)

HI = 750 mgHC.g

-1 TOC

HI = 300 mgHC.g

-1 TOC

Lower diatomite Upper diatomite

Littoral unit E6 MWD

E5 Turbidite Events 1 and 4

0

0 5 10 15 20 25 30

Plateau

PAV 08

Basin

PAV1 2

Littoral

PAV 10 -E

E6 MWD (AD 600)

Diatomite

E5 MWD

Diatomite

Mineral basal unit

E5 Turbidite

(AD 1300)

Fig. 23.9 Characterization of Pavin sediments origin and sediment
source based on diffuse spectral refl ectance Q7/4 diagram ( left ) and
Rock-Eval pyrolysis represented by S2 vs. TOC diagram ( right ) for
cores PAV10-E (littoral), PAV08 (plateau) and PAV12 (basin). In the
Q7/4 diagram, the diffuse spectral refl ectance signature of littoral
deposit, diatomite , Mass-Wasting Deposit (MWD), Turbidite and
Mineral Basal unit are compared to the fi ve distinct poles of sediments
defi ned by Debret et al ( 2011 ): Iron-Rich deposits ( a ); Organic-rich

deposits dominated Melanoidine type ( b ); Organic-rich deposits domi-

nated by altered organic matter ( c ); Organic-rich deposits dominated by

Chlorophyll and by-products ( d ); Clayey deposits ( e ) and Carbonate

deposits ( f ). In the S2 vs. TOC diagram, Total Organic Carbon (TOC),

together with Hydrogen Index (HI) and S2 (thermal cracking of the

hydrocarbon compounds) are illustrated. The two linear domains of the

hydrogen index (HI = 750 and HI = 300 mgHCg −1 TOC) corresponding

to algal and terrestrial poles, respectively, are also represented

L. Chassiot et al.