We propose a novel method to reconstruct the six parameters of the paleostress tensor. The method involves three major steps: (1) measurement and inversion of vein attitudes to determine the reduced paleostress tensor, (2) determination of pore pressures using fluid inclusion (FI) isochores and mineral geothermometry, (3) final adjustment of the Mohr circle and estimation of stress magnitudes using geomechanical constraints from the literature. Owing to its outstanding 3D exposures, we selected Panasqueira Mine, central Portugal, as natural laboratory to develop and test our approach. We measured 684 quartz veins, ∼800 FIs in quartz and the geochemical composition of 10 arsenopyrite samples. The inversion of the veins resulted in a reverse stress regime with σ₁ trending ∼ NW-SE, Φ = 0.6 and a driving stress ratio of R’ = 0.19. We estimated a lithostatic pressure of 270 MPa (min. 230 MPa and max. 300 MPa) during the major mineralisation stage of the veins of Panasqueira (i.e. MOSS-MSS stage). Finally, the adjustment of the Mohr circle resulted in differential stresses too low to trigger shear failure and in the range from 45 to 89 MPa, and pore pressures exceeding lithostatic pressure by 8.5–17 MPa to open the discontinuities during MOSS-MSS mineralisations.

我们提出了一种重建古应力张量六个参数的新方法。该方法包括三个主要步骤：(1) 测量和反演矿脉姿态以确定降低的古应力张量，(2) 使用流体包裹体 (FI) 等距线和矿物地温测量法确定孔隙压力，(3) 莫尔圆的最终调整并使用文献中的地质力学约束估计应力大小。由于其出色的 3D 曝光，我们选择了葡萄牙中部的帕纳斯奎拉矿作为天然实验室来开发和测试我们的方法。我们测量了 684 个石英脉、约 800 个石英中的 FIs 和 10 个毒砂样品的地球化学成分。静脉的反转导致反向应力状态与 σ ₁趋势 ∼ NW-SE，Φ = 0.6 和 R' = 0.19 的驱动应力比。我们估计在Panasqueira 矿脉的主要成矿阶段（即MOSS-MSS 阶段）的岩石静压为270 MPa（最小230 MPa 和最大300 MPa）。最后，莫尔圆的调整导致差异应力太低而无法触发剪切破坏，并且在 45 至 89 MPa 的范围内，并且孔隙压力超过岩石静压 8.5-17 MPa 以打开 MOSS-MSS 矿化过程中的不连续性。