Stibnite - Le Semnon mine

Work Package 1: Geological processes that control the location and characteristics of mineralisation


The 3D characterisation of the geological and structural framework that host Sb mineralisation and definition of ores paragenesis, involving also structural, petrographic and geochronological studies


Numerous Sb deposits and associated metals (i.e. W, Hg, As, Au) are known in the West-European Variscan belt, especially in the Central Iberian Zone (CIZ), where a large diversity of Sb deposits occur (Gumiel & Arribas 1987). Recent results (e.g. Pochon 2017), on the French counterpart of the CIZ (Armorican Massif), have highlighted a Sb mineralising event at ca. 360 Ma, coeval with a major mafic magmatism and with the end of Variscan continental subduction. Because of lithologies and geological structures are similar in the CIZ, this work package will focus on the re-assessment of the geology of the key Iberian Sb deposits and the understanding of global processes controlling the location of Sb deposits through the Ibero-Armorica arc. The WP1 will integrate a multi-method approach (i.e. field works, geophysics, geochemistry and experimentation) to better constrain the hydrothermal and geological history of Sb mineralisation. The aim is to bring new data about processes leading to the formation of Sb deposits in order to build 3D geological and numerical models. Consequently, this WP1 will involves three partners and will be the bedrock necessary to successfully complete the WP2 and WP3.

Task 1.1 - Characterisation, dating and new metallogenic models for Sb-W-Hg ore deposits. Co-Lead: H.
Sant'Ovaia, FCUP and R. Augier, ISTO.

Task 1.2 - Evaluation of mafic and sedimentary rocks as metal source. Lead: G. Iacono-Marziano, ISTO

Task 1.3 - 3D reconstruction of selected key areas to constrain metal transfers in the crust. Lead: L. Guillou-Frottier, BRGM


WP Leader: Alexandre Lima (FCUP)