Abstract

The ore deposits in the northernmost region of Chile (17.5–19.5°S) during the Cenozoic era are situated within three significant Andean metallogenic belts: the Paleocene to early Eocene belt, the middle Eocene to early Oligocene belt and the Miocene to Early Pliocene belt [1]. These belts have a crucial role in the formation and distribution of porphyry copper deposits, shallow-level intrusions associated mostly with thick (>45 km) magmatic arcs. Studies have extensively investigated the occurrence of these types of deposits with regional-scale mineralization events. Particularly, between latitudes 18° and 19°, and longitudes 69° to 70° approximately, the porphyry copper prospects are part of the Paleocene-Early Eocene belt. In this work we present a case study as an applied case at greenfield scale of the known ore deposits that coincide with these belts in Lluta Valley, Arica and Parinacota Region, focusing primarily on the Dos Hermanos and Campanani which are the largest ones known to date. The study is through local earthquake tomography (LET), a geophysical technique that has been recently applied to better understand the subsurface crustal architecture beneath mineral deposits as the Cerro Colorado deposit. The integration with the geological knowledge of the area will help us to find a spatial correlation between Vp/Vs ratio anomalies with ore deposits known in the area and to understand their geological formation.