GEOLOGY AND MINERALIZATION
El Chanate’s main structural feature is the Chanate fault zone, a 7 km-long northwest-striking, variably southwest-dipping structure. The area is underlain by deformed sedimentary rocks of the Late Jurassic-Early Cretaceous Bisbee Group and the Late Cretaceous Chanate Group, which locally are overlain by andesites of the Cretaceous El Charro volcanic complex.
The sedimentary strata are locally intruded by andesitic sills and dikes, a microporphyritic latite, and a diorite stock. These strata comprise mudstone, siltstone, sandstone, conglomerate, shale, and limestone.
Sandstone, conglomerate, and lesser mudstone that lie above the Chanate fault are of the Middle Cretaceous Chanate Group. Below the fault, siltstone and sandstone lenses are assigned to the Arroyo Sasabe Formation of the Lower Cretaceous Bisbee Group.
Alteration and mineralization associated with the Chanate fault zone are exposed across a northwest strike length of over 3.5 km. The rock units in this zone are altered to varying degrees by sericite, pyrite, ankerite, and quartz veining.
In surface outcrops the mineralized zone is distinguished by its bleached appearance relative to unmineralized rock. Sub-parallel sheeted zones of quartz veinlets form thick, mineralized lenses, within a larger area of sub-economic but anomalous gold concentrations.