The Mudpuppy-Waterdog prospect, an alkalic copper-gold porphyry system in the Nogal-Bonito mining district, Lincoln County, New Mexico
— Michael S. Fulp and Lee A. Woodward

The Mudpuppy-Waterdog prospect occurs in the Nogal-Bonito district, Lincoln County, New Mexico, within a north-trending belt of mid-Tertiary, gold-bearing alkalic intrusions and is interpreted as the top of an alkalic copper-gold porphyry system. It is hosted by a syenite-to-monzonite porphyry stock that is concentrically zoned inward from propylitic-argillic-phyllic alteration to a core of silica-limonite breccias. Rock and soil geochemical anomalies of Cu-Au-Te-Mo are coincident with the phyllic and silica-limonite breccia zones. Limited, shallow drill-hole data indicate increased Cu-Au values at depth compared with surface geochemistry. The broad zone of alteration and geochemical anomalies occurs along a zone of strong northnortheast- trending fractures. We suggest the geochemical anomalies represent leakage halos along fractures from a sulfide-rich potassic core at depth. The Mudpuppy-Waterdog prospect has potential to host a largetonnage alkalic copper-gold porphyry deposit.