Distinct lake level lowstand in Lake Prespa (SE Europe) at the time of the 74 (75) ka Toba eruption

Abstract. The 74 (75) ka Toba eruption in Sumatra, Indonesia,
is considered to be one of the largest volcanic events during
the Quaternary. Tephra from the Toba eruption has been
found in many terrestrial and marine sedimentary deposits,
and acidity peaks related to the eruption have been used to
synchronize ice core records from Greenland and Antarctica.
Seismic profiles and sedimentological data from Lake
Prespa on the Balkan Peninsula, SE Europe, indicate a lake
level lowstand at 73.6±7.7 ka based on ESR dating of shells.
Tephrostratigraphy, radiocarbon dating and tuning of the total
organic carbon content with the NGRIP isotope record,
corroborate that the lake level lowstand was a short-term
event superimposed on the general cooling trend at the end of
MIS 5, most likely at the onset of the Greenland Stadial GS-
20. Acknowledging that tectonic events or karst processes
could have triggered this lake level lowstand, the chronological
correspondence between the lowstand and the Toba eruption
is intriguing. Therefore a Toba-driven short-term shift
to aridity in the Balkan region, leading to lake level changes
and triggering spatial expansion events in one of the lake’s
most abundant benthic species, the carino mussel Dreissena
presbensis, cannot be excluded.