Publication Date:
2021-12-15
Description:
We present new tephrostratigraphic records from the late MIS 5 (ca 110e80 ka) terrestrial sediments
from southern and central Italy. On the one hand, the central Italy record consists of an outcropping
lacustrine sequence from the Sulmona intermountain basin that contains four trachyticephonolitic
tephra layers (POP3, POP2a, POP2b, POP1), all of which show a K-alkaline affinity that is typical for
the Roman co-magmatic Province. The POP3 and POP1 layers were dated by 40Ar/39Ar method at
106.2 1.3 ka (2s) and 92.4 4.6 ka (2s), respectively. The sequence in southern Italy, on the other
hand, is represented by post-Tyrrhenian coastal deposits of the Cilento area, Campania, which contain
two trachytic layers (CIL2, CIL1) that show the same K-alkaline affinity. Based on their chemical
compositions and radiometric ages, POP3 and POP1 are firmly correlated with the marine tephra layers
X-5 (105 2 ka) and C-22 (ca 90 ka), which, in turn, match tephras TM-25 and TM-23-11, respectively,
in the lacustrine sequence of Lago Grande di Monticchio (southern Italy). Of note, the POP1 layer also
matches the Adriatic Sea tephra PRAD 2517 that was previously correlated with the older X-5 layer. The
tephra couplet POP2a and POP2b (ca 103 and 103.5 ka, extrapolated ages) are compatible with the TM-
24b and TM-24-3 tephras in Monticchio, which match both the stratigraphic positions and the chemical
compositions. In the Cilento area, as well as the already described X-6 layer (ca 108 ka) (CIL2), we
recognise a new stratigraphic superimposed layer (CIL1) that matches the POP3/TM-25/C-27/X-5
Mediterranean marker(s). In summary, the data presented here provide new chemical and 40Ar/39Ar
chronological constraints towards a robust late MIS 5 tephrostratigraphy of the central Mediterranean,
although at the same time, they also reveal how the tephrostratigraphy itself might be flawed when
dealing with tephra markers that are not adequately constrained and characterised.
Description:
Published
Description:
31-45
Description:
1V. Storia eruttiva
Description:
JCR Journal
Keywords:
Geochemical fingerprinting
;
40Ar/39Ar dating
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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