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Author: Admin | 2025-04-28
Potassic radiometric anomalies such as at the Belen prospect with two porphyry targets at Ricardo Herrera and Sortilegio and Valiente Norte, where four magnetic targets have been identified.The Belen Cu-Au target contains a linked porphyry copper-gold and epithermal gold mineral system which include a number of prospect areas described below in more detail.Ricardo Herrera Copper-Gold Porphyry TargetA linked porphyry copper-gold and epithermal gold mineral system has been identified at Belen within an 8 km by 2 km trend. Recent detailed field work has identified a leached copper-gold porphyry with well-developed quartz veining at upper topographic levels and evidence for an enriched chalcocite blanket sampled over 1 km within lower lying creeks at the Ricardo Herrera Copper-Gold Porphyry Target. This coincides with a highly anomalous Cu-Au-Mo soil anomaly over a 1,600 m by 800 m area above a mapped and radiometrically dated Miocene-age porphyry intrusion.The Ricardo Herrera porphyry stock was intruded in several stages, broadly termed early, intermineral, and late, all interpreted within a relatively short time interval. The early stages are hornblende feldspar porphyries of andesitic composition, whereas the late stages consist of unaltered feldspar porphyries of andesitic composition. The intrusions caused contact metamorphism and hydrothermal alteration that partially obliterated the original texture and composition of the sedimentary country rocks. Two early porphyries are identified. The first being an intermediate argillic (chlorite from secondary biotite-white micas) with relicts of potassic alteration (secondary biotite-magnetite) with "EB" type veinlets (early biotite), M-type (magnetite) veinlets and few A-type veinlets (quartz). The second early porphyry intrusion is characterized by A-type veinlets, jarosite-goethite iron oxide veinlets with phyllic alteration (quartz-white sericite), argillic alteration (kaolinite). The intermineral stock is dominated by supergene argillic alteration and propylitic alteration (chlorite, epidote).In porphyry copper systems, the area with the highest copper grade often corresponds to the early porphyries. The focus of the detailed geological mapping has therefore been to identify this area and to sample it with systematic rock sampling.At Ricardo Herrera the combined early hornblende feldspar porphyry is at least covering an area of 850 m x 250 m on the surface. But limited exposures, that are mostly constrained to creeks and rare outcrops, make it difficult to define the true area. Observed copper minerals include pyrite, chalcopyrite, chalcocite, molybdenite, neotocite and chrysocolla mineralization. The intermineral hornblende feldspar porphyry contains supergene argillic alteration and minor neotocite. Moderate to pervasive secondary biotite alteration is common throughout the host rock.
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