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(a)
(b)
Fig. 2 a Total organic carbon (TOC) accumulation rates in sapropel S1 (observed range indicated
by grey bar) (De Lange et al.
2008
;M
bius et al.
2010
) compared to TOC flux calculated from
EMS sediment traps (MID 03 shallow and MID 01
ö
bius et al.
2010
). Data indicate
that present day export production would suffice to create a S1-like sapropel, under anoxic deep
water conditions. b Temporal succession of major benthic ecosystem changes at different water
depth, associated with sapropel S1 (modi
ed from Schmiedl et al.
2010
). The ecosystem changes
are indicated by passing of an OI threshold value of 0.5. The dashed lines display mean values of
ecosystem shifts, the solid line marks the average for the onset of sapropel formation. The time
window of EMS sapropel S1 formation and its interruption around 8.2 ka BP are indicated. YD
Younger Dryas
-
03 deep) (M
ö
By combining proxy data and modeling results we were able to explore the
physical and biogeochemical processes and time-scales leading from enhanced
insolation and seasonality and local hydrological perturbations to the formation of
anoxia in the EMS and its regional environmental expression during the early
Holocene. Based on this integrative approach we reconciled previously contradic-
tory results, particularly concerning the observed SST patterns. We reconstructed a
complex regional pattern of surface water mixing, rapid expansion of dysoxia and
anoxia within a few centuries, and demonstrated that sapropel S1 was deposited
under oligotrophic conditions refuting the
“
high-productivity
”
hypothesis.
References
Adloff F, Mikolajewicz U, Kucera M, Grimm R, Maier-Reimer E, Schmiedl G, Emeis KC (2011)
Upper ocean climate of the Eastern Mediterranean Sea during the Holocene insolation
Adloff F (2011) Early Holocene Eastern Mediterranean ocean climate and the stability of its
overturning circulation. Rep Earth Sys Sci 107:1
-
157
Cramp A, O
´
Sullivan G (1999) Neogene sapropels in the Mediterranean: A review. Mar Geol
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