Integrated Geostatistical–Geotechnical Modelling and Mining Method Assessment of the Tala Hamza Zn–Pb Deposit, Northern Algeria

The Tala Hamza zinc–lead deposit, located in the Amizour region south of Béjaïa (Northern Algeria), is one of the largest base-metal resources in the Maghreb. This study presents an integrated geological, geostatistical, and geotechnical assessment to improve resource estimation and optimise the mining strategy. Geostatistical analyses of drilling data revealed moderate to strong spatial continuity of zinc and lead grades, with variogram ranges of 120–200 m along the main structural trends. Ordinary Kriging and conditional simulations produced three-dimensional grade and uncertainty models, confirming anisotropy consistent with the tectonic framework and identifying higher uncertainty near fault zones. These results were integrated with geotechnical investigations and FLAC3D numerical modelling to validate the Descending Backfilled Chamber (DBC) mining method. The DBC approach, combined with cemented backfilling, ensures mechanical stability, limits dilution, and maximises ore recovery. This multidisciplinary framework demonstrates the effectiveness of coupling geostatistical and geotechnical modelling for reliable resource evaluation and sustainable mine design, providing a reference for similar base-metal deposits in Algeria and beyond.