De Landro G, Vanorio T, Muzellec T, Russo G, Lomax A, Virieux J, Zollo A
Department of Physics 'Ettore Pancini', University of Naples 'Federico II', Naples, Italy.
Department of Earth and Planetary Sciences, Stanford Rock Physics and Geomaterials Laboratory, Stanford University, Stanford, CA, USA.
Nat Commun. 2025 May 23;16(1):4814. doi: 10.1038/s41467-025-59821-z.
Campi Flegrei is an active caldera in a populated area, currently experiencing significant ground uplift and seismicity. Leveraging seismicity relocations, here we obtain high resolution, 3D P- and S-wave seismic images which we combine with a tailored rock physics experiment to define key features of the caldera's structure: gas-rich reservoir below 2 km depth, deformed caprock at 1-2 km depth, and basement below 3.5 km depth. Seismicity migrates downwards from the caprock and changes in stress loading trigger deeper, higher events along the inner-caldera boundary faults. The reservoir closely correlates the area of maximum uplift, where deformation acceleration due to pore-fluid pressure is corroborated by laboratory experiments using site-relevant rock. The interaction between the pressurized gas-reservoir and the confining caprock drives the ground uplift. Our results indicate that seismic activity and the potential for a phreatic explosion should be considered as plausible scenarios, prompting a re-evaluation of the hazard assessment.
弗莱格雷火山区是一个位于人口密集地区的活火山口，目前正经历着显著的地面隆起和地震活动。利用地震重新定位技术，我们在此获得了高分辨率的三维P波和S波地震图像，并将其与定制的岩石物理实验相结合，以确定火山口结构的关键特征：深度2公里以下的富气储层、深度1至2公里处的变形盖层以及深度3.5公里以下的基底。地震活动从盖层向下迁移，应力加载的变化会触发沿火山口内边界断层更深、更强的地震事件。储层与最大隆起区域密切相关，在该区域，孔隙流体压力导致的变形加速通过使用与现场相关岩石的实验室实验得到了证实。加压气藏与承压盖层之间的相互作用推动了地面隆起。我们的结果表明，地震活动和潜水爆炸的可能性应被视为合理的情况，这促使对灾害评估进行重新评估。
