The Late-Holocene evolution of the Miseno area (south-western Campi Flegrei) as inferred by stratigraphy, petrochemistry and 40 Ar/ 39 Ar geochronology:Chapter 6 in Volcanism in the Campania Plain — Vesuvius, Campi Flegrei and Ignimbrites

Donatella Insinga; Andrew T. Calvert; Marvin A. Lanphere; Vincenzo Morra; Annamaria Perrotta; Marco Sacchi; Claudio Scarpati; James Saburomaru; Lorenzo Fedele

doi:10.1016/s1871-644x(06)80020-3

USGS · 70178406

The Late-Holocene evolution of the Miseno area (south-western Campi Flegrei) as inferred by stratigraphy, petrochemistry and 40 Ar/ 39 Ar geochronology:Chapter 6 in Volcanism in the Campania Plain — Vesuvius, Campi Flegrei and Ignimbrites

Donatella Insinga·Andrew T. Calvert·Marvin A. Lanphere·Vincenzo Morra·Annamaria Perrotta·Marco Sacchi·Claudio Scarpati·James Saburomaru·Lorenzo Fedele

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Abstract

This study on terrestrial and marine successions increases the understanding of the Late-Holocene volcanological and stratigraphical evolution of the south-western part of Campi Flegrei caldera. Stratigraphic data derived from field studies of two major tuff vents located along the coastal zone, namely Porto Miseno and Capo Miseno, clearly indicate that the Porto Miseno tuff ring slightly predates the Capo Miseno tuff cone. 40 Ar/ 39 Ar step-heating experiments, carried out on fresh sanidine separates from pumice samples, yielded a plateau age of 5090±140 yr BP for Capo Miseno and 6490±510 yr BP for Porto Miseno vent, thus confirming field observations. The volcanoclastic input derived from this recent and intense eruptive activity played a major role in the inner-shelf stratigraphic evolution of the Porto Miseno Bay deposits that have been drilled up to 40 m depth off the crater rim. The cored succession is characterised by transgressive marine deposits (mostly volcanic sand) with two intercalated peat layers (t 1 and t 2 ), dated at 3560±40 yr BP and 7815±55 yr BP ( 14 C), respectively, interbedded with a 1–5 m thick pumice layer (tephra C). Peat layers have been chronostratigraphically correlated with two widespread paleosols onland while petrochemical analyses allowed us to correlate tephra C with the Capo Miseno tuff cone deposits. The results presented in this study imply a Late-Holocene volcanic activity that is also well preserved in the marine record in this sector of the caldera where a new chronostratigraphic reconstruction of the eruptive events is required in order to better evaluate the hazard assessment of the area.

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Source-reported bounding extent: 40.75° to 41° latitude; 14° to 14.3° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Donatella Insinga, Andrew T. Calvert, Marvin A. Lanphere, Vincenzo Morra, Annamaria Perrotta, Marco Sacchi, Claudio Scarpati, James Saburomaru, Lorenzo Fedele. 2006. The Late-Holocene evolution of the Miseno area (south-western Campi Flegrei) as inferred by stratigraphy, petrochemistry and 40 Ar/ 39 Ar geochronology:Chapter 6 in Volcanism in the Campania Plain — Vesuvius, Campi Flegrei and Ignimbrites. https://doi.org/10.1016/s1871-644x(06)80020-3

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