Publication Date:
2022-02-09
Description:
The eruptive history of Pantelleria has been marked by the eruption of nine peralkaline ignimbrites,
with inter-ignimbrite episodes from small, local volcanic centres. New whole-rock geochemical
data are presented for seven ignimbrites and used with published data for younger units to track
compositional changes with time. From 190 ka, silicicmagmatismwas dominated by comenditic trachyte
to comendite compositions, evolving along generally similar liquid lines of descent (LLOD). The
final ignimbrite, the Green Tuff ( 46 ka), was tapped from a compositionally zoned pantelleritic upper
reservoir to a trachytic mush zone. Younger (20–7 ka) silicic magmatism has been relatively small
scale, with compositions similar to the earliest pre-Green Tuff pantelleritic ignimbrite (Zinedi). These
data suggest that the comenditic reservoirs may have been emplaced at deeper levels than the pantelleritic
reservoirs. While both types of series evolved along similar LLOD dominated by fractionation
of alkali feldspar, it is the fractionation of iron that determines whether comendite or pantellerite is
produced. The deeper reservoirs were more oxidizing and wetter, thus leading to the crystallization of
magnetite and therefore the fractionation of iron.
Description:
Published
Description:
133-149
Description:
3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
Description:
JCR Journal
Keywords:
Pantelleria, Ignimbrite, Magma reservoirs, Compositional changes with time, Comendite, Pantellerite.
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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