Publication Date:
2020-11-19
Description:
The Campanian Ignimbrite eruption dispersed ash
over much of the central eastern Mediterranean Sea and eastern
Europe. The eruption started with a Plinian phase that was
followed by a series of pyroclastic density currents (PDCs)
associated with the collapse of the Plinian column and the
caldera. The glass compositions of the deposits span a wide
geochemical range, but the Plinian fallout and PDCs associated
with column collapse, the Lower Pumice Flow, only
erupted the most evolved compositions. The later PDCs, the
Breccia Museo and Upper Pumice Flow, erupted during and
after caldera collapse, tap a less evolved component, and intermediate
compositions that represent mixing between the
end-members. The range of glass compositions in the
Campanian Ignimbrite deposits from sites across the central
and eastern Mediterranean Sea allow us to trace the dispersal
of the different phases of this caldera-forming eruption. We
map the fallout from the Plinian column and the plumes of fine
material associated with the PDCs (co-PDCs) across the entire
dispersal area. This cannot be done using the usual grain-size methods as deposits in these distal regions do not retain characteristics
that allow attribution to either the Plinian or co-
PDC phases. The glass compositions of the tephra at ultradistal
sites (〉1500 km from the vent) match those of the uppermost
PDC units, suggesting that most of the ultra-distal
dispersal was associated with the late co-PDC plume that
was generated during caldera collapse.
Description:
Published
Description:
45
Description:
3V. Proprietà dei magmi e dei prodotti vulcanici
Description:
JCR Journal
Keywords:
Caldera-forming eruption
;
Ash dispersal
;
Plinian
;
Tephra
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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