Vertical ground displacement at Campi Flegrei (Italy) in the fifth century: Rapid subsidence driven by pore pressure drop

Autor: Alberto Comastri, Giorgio Spada, Antonio Costa, Francesca Quareni, Florence Colleoni, Micol Todesco
Přispěvatelé: Micol Todesco, Antonio Costa, Alberto Comastri, Florence Colleoni, SPADA, GIORGIO, Francesca Quareni
Rok vydání: 2014
Předmět:
Zdroj: Geophysical Research Letters. 41:1471-1478
ISSN: 0094-8276
DOI: 10.1002/2013gl059083
Popis: Campi Flegrei (Italy) caldera has experienced episodes of ground deformation throughout its geological history, alternating between uplift and subsidence phases. Although uplift periods are typically more alarming, here we focus on subsidence, looking for its driving mechanisms and its role in the caldera evolution. Historical and archaeological records constrain ground deformation over the last two millennia. Here we revise such records and combine them with published radiometric dating and with the simulation of sea level change. The resulting analysis highlights for the first time a rapid subsidence during the fifth century. We show that rate and magnitude of this subsidence are consistent with the compaction of porous material caused by a pressure drop of ~ 1 MPa within the hydrothermal system. We interpret this event as the decompression of the hydrothermal system following an unrecognized episode of unrest, during Roman times. These findings redefine the pattern of ground deformation and bear important implications for volcanic hazard assessment.
Databáze: OpenAIRE