| Popis: |
One visible volcanic ash layer and 21 non-visible, cryptotephra horizons have been identified in the M72/5-25-GC1 core from the south-east Black Sea that spans the last ∼60 ka. Glass chemistry suggests that the tephras derive from Italian, Hellenic and Turkish sources. The visible tephra layer is trachytic in composition and has been correlated to the ∼39 ka Campanian Ignimbrite super-eruption from Campi Flegrei caldera, Italy. Two cryptotephra layers are associated with eruptions from Acigol volcano (Turkey) around the Last Glacial Maximum, another is linked to activity at Erciyes Dagi in the Early Holocene (Perikartini or Karagullu), and a cryptotephra layer near the top of the core correlates to the ∼3.6k cal a BP Minoan (marine Z2) tephra from Santorini (Thera), Greece. This extends the known dispersal area for all these volcanic ash units. Many other calc-alkaline rhyolite layers preserved in the core are likely to be from central Anatolian sources but the lack of detailed proximal data for many of the volcanoes in the region prohibits further correlations. The tephrostratigraphy and glass compositional data presented here allow the tephra layers to be used to correlate sedimentary archives across the region, and help to extend the Mediterranean tephrochronology framework towards the east. |
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