Publication Date:
2021-11-09
Description:
The Punta delle Pietre Nere (Gargano, Southern Italy) igneous body is constituted by gabbroic and syenitic rocks
with lamprophyric affinity of different age (58 and 62 Ma, respectively). The chemical composition of the
minerals clearly indicates that there is no genetic relationship between the two lithotypes, in agreement with
their significant age difference. The chemical (trace elements) and Sr-Nd-Pb-isotopic composition of these
rocks highlights an “anorogenic” geochemical affinity derived from mixed DMM-HIMU-EM mantle reservoirs,
similarly to other Paleogene-Oligocenemagmatic provinces in the Circum-Mediterranean Area. In past literature,
these features were interpreted as evidences for enriched asthenospheric mantle plume upwelling from deep
regions beneath the Western Europe. Here we suggest that the HIMU-like composition of Punta delle Pietre
Nere rocks is related to a lithosphericmantle source bearing amphibole-rich veins, resulting from crystallization
of melts within the amphibole stability field in presence of H2O, as shown by several experimental works.
Our results suggests partial melting at 70–90 km depth, which corresponds to the spinel-garnet transition
(2.5–3.5 GPa) close to the amphibole stability limit (~90–110 km and 2.5–3.5 GPa).
Description:
Published
Description:
316-328
Description:
3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
Description:
JCR Journal
Keywords:
Punta delle Pietre Nere Anorogenic magmatism Isotope geochemistry Mantle plume
;
Anorogenic magmatism
;
Mantle plume
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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