Abstract Hydrothermal regions are affected by a wide variety of phenomena, including ground inflation and deflation episodes. Among them, calderas offer the opportunity to study the complex interactions between magmatic processes at depth and permeable rocks saturated with fluids in the upper sedimentary layers. One of such regions is the Campi Flegrei caldera in southern Italy, where several source models have been applied over the years to reproduce the ground displacement and seismicity observed during the most recent phase of major unrest (1982–1984). The present work aims at introducing a new source model consisting of a thermo-poro-elastic inclusion embedded in a homogeneous poroelastic half-space. The inclusion is meant to represent a permeable rock layer stressed and strained by hot and pressurized volatiles released upward by an underlying magmatic reservoir and is modeled as a thin horizontal disk inside which a sudden change of temperature and pore pressure occurs. We provide semi-analytical solutions for the displacement and stress fields both within and outside the source and check them by comparison with those obtained through a fully numerical approach. Results provided by our model are compared with two other deformation source models often used to describe volcanic environments in terms of pressurized cavities describing a spherical magma chamber (Mogi source) or a sill-like magma intrusion (Fialko source). For the Campi Flegrei 1982–84 unrest, our model provides a better reproduction of ground deformation data and manages to explain the widespread presence of compressive focal mechanisms, since the stress field promoted both inside and outside the thermo-poro-elastic inclusion is very different from pressurized cavities.

中文翻译：

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热液区的变形和应力：半空间中盘状夹杂物的情况

摘要 热液区受到多种现象的影响，包括地面膨胀和通货紧缩事件。其中，破火山口为研究深部岩浆过程与上层沉积层中充满流体的渗透性岩石之间复杂的相互作用提供了机会。其中一个地区是意大利南部的 Campi Flegrei 火山口，多年来，在那里应用了几种震源模型来重现在最近一次重大动乱阶段（1982-1984 年）观察到的地面位移和地震活动。目前的工作旨在引入一种新的源模型，该模型由嵌入均匀多孔弹性半空间中的热孔弹性夹杂物组成。包裹体意在代表由下伏岩浆储层向上释放的热和加压挥发物应力和应变的可渗透岩石层，并被建模为一个薄的水平圆盘，在该圆盘内温度和孔隙压力发生突然变化。我们为源内外的位移和应力场提供半解析解，并通过与通过完全数值方法获得的结果进行比较来检查它们。我们的模型提供的结果与其他两个常用于描述火山环境的变形源模型进行了比较，这些变形源模型用加压腔来描述球形岩浆房（Mogi 源）或类似窗台的岩浆侵入（Fialko 源）。对于 Campi Flegrei 1982–84 年的骚乱，