Our data clearly image, for the first time, the offshore geometry of the NYT caldera ring-fault zone, as well as the style and timing of volcano-tectonic deformation associated with the late stage evolution of the NYT inner caldera resurgence. Our interpretation suggests that since 15 ka the offshore sector of NYT inner caldera underwent significant deformation and uplift (with minor subsidence episodes) that occurred at almost the same rate as the post-glacial sea-level rise. Particularly, the inner Pozzuoli Bay started to deform soon after 15 ka BP, when sea-level rise was initially faster than uplift. This caused a general increase of the accommodation space that was progressively filled up by volcaniclastic sediments. Since ca. 8 ka BP, along with the mid Holocene decrease in the rate of the sea-level rise, the early NYT resurgent structure was then uplifted up to the sea-level or even to partial subaerial exposure. From ca. 8 to 5 ka BP two distinct layers of volcaniclastic resediments, mostly represented by gravity flow deposits, formed throughout the Bay. A significant post- Roman (post 2 ka BP) subsidence phase of ca 10 m is then recorded offshore Pozzuoli by the drowning of the infralittoral prograding wedge below the present-day fair-weather wave base
The submerged structure and stratal architecture of the Neapolitan Yellow Tuff (NYT) caldera, offshore the Campi Flegrei, (Eastern Tyrrhenian Margin): New insights from high resolution seismics and gravity core data
Sacchi M;Molisso F;Insinga DD
2012
Abstract
Our data clearly image, for the first time, the offshore geometry of the NYT caldera ring-fault zone, as well as the style and timing of volcano-tectonic deformation associated with the late stage evolution of the NYT inner caldera resurgence. Our interpretation suggests that since 15 ka the offshore sector of NYT inner caldera underwent significant deformation and uplift (with minor subsidence episodes) that occurred at almost the same rate as the post-glacial sea-level rise. Particularly, the inner Pozzuoli Bay started to deform soon after 15 ka BP, when sea-level rise was initially faster than uplift. This caused a general increase of the accommodation space that was progressively filled up by volcaniclastic sediments. Since ca. 8 ka BP, along with the mid Holocene decrease in the rate of the sea-level rise, the early NYT resurgent structure was then uplifted up to the sea-level or even to partial subaerial exposure. From ca. 8 to 5 ka BP two distinct layers of volcaniclastic resediments, mostly represented by gravity flow deposits, formed throughout the Bay. A significant post- Roman (post 2 ka BP) subsidence phase of ca 10 m is then recorded offshore Pozzuoli by the drowning of the infralittoral prograding wedge below the present-day fair-weather wave baseI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
