Abstract # 28 Category: Technical developments in exploration including AI / ML studies

Title: Hyperspectral imaging in Pasco Complex and applications in exploration, Cerro Pasco District, Peru

Presenter: Miguel Martinez, Senior Geochemist, ALS

Abstract: After 80 years of industrial-scale mining, the Pasco Complex keeps revealing new styles of

mineralization, new exploration targets, and ultimately, new resources and reserves. This complex is

formed by several types of mineralization formed during the intrusion of Oligocene porphyries into Late

Triassic carbonated rocks (Chambara Formation, part of Pucara Group), including Zn-Pb-Ag-Cu skarn, Pb-

Zn-Ag breccias, Zn-Pb-Ag-Cu±Au intermediate sulfidation polymetallic veins, Pb-Zn-Ag stratabound in

sandstones, and Cu-Au±Mo porphyry.

Recently, hyperspectral core imaging was performed in 3984.5 meters of drill cores from Pasco

Complex, using imaging spectroscopy to collect continuous mineralogy. Two types of product were

generated, image products that preserve the textural context of minerals, and numerical data extracted

from spectral features such as absorptions, in the visible-near infrared and short-wave infrared, and

Reststrahlen peaks in the long-wave infrared.

This presentation shows the results of the hyperspectral imaging and its implications in the exploration

of the district, such as: identification of intrusive pulses associated with early and late alteration of the

Santa Barbara porphyry as a result of the characterization of micas using the shortwave infrared range,

and the use of the longwave infrared range in the differentiation of proximal and distal environments in

the Atacocha skarn and its prograde and retrograde alteration domains.

.

Authors: Aline dos Anjos, NEXA

Mervin Tapia, NEXA

Jonas Mota, NEXA

Miguel Martinez, ALS

Exploration Insights Abstracts Page 28 of 49