Publication Date:
2021-06-16
Description:
New 40Ar/39Ar and 14C ages have been found for the Albano multiple maar pyroclastic units and underlying 25
paleosols to document the most recent explosive activity in the Colli Albani Volcanic District (CAVD) near 26
Rome, Italy, consisting of seven eruptions (Albano 1 27
^
=
^
oldest). Both dating methodologies have been applied
on several proximal units and on four mid-distal fall/surge deposits, the latter correlated, according to two 28
current different views, to either the Albano or the Campi di Annibale hydromagmatic center. The 40Ar/39Ar 29
ages on leucite phenocrysts from the mid-distal units yielded ages of ca. 72 ka, 73 ka, 41 ka and 36 ka BP, 30
which are indistinguishable from the previously determined 40Ar/39Ar ages of the proximal Albano units 1, 2, 31
5 and 7, thus confirming their stratigraphic correspondence. 32
Twenty-one 14C ages of the paleosols beneath Albano units 3, 5, 6 and 7 were found for samples collected 33
from 13 proximal and distal sections, some of which were the same sections sampled for 40Ar/39Ar 34
measurements. The 14C ages were found to be stratigraphically inconsistent and highly scattered, and were 35
systematically younger than the 40Ar/39Ar ages, ranging 36
^
from 35 ka
^
to 3 ka. Considering the significant
consistence of the 40Ar/39Ar chronological framework, we interpret the scattered and contradictory 14C ages 37
to be the result of a variable contamination of the paleosols by younger organic carbon deriving from the 38
superficial soil horizons. 39
These results suggest that multiple isotopic systems anchored to a robust stratigraphic framework may need 40
to be employed to determine accurately the geochronology of the CAVD as well as other volcanic districts. 41
Description:
Published
Description:
203-213
Description:
3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
Description:
JCR Journal
Description:
open
Keywords:
40Ar/39Ar 14C geochronology Albano maar Central Italy
;
04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article