Victoria Carbonate‐Base Metal Gold Deposit and Its Significance in the Mankayan Mineral District, Luzon, Philippines

Abstract

Abstract:The Victoria gold deposit is a low-sulfidation style epithermal carbonate-base metal gold deposit discovered in 1995 in the Mankayan mineral district, northern Luzon, Philippines. It occurs just south of a high-sulfidation copper-gold orebody (Lepanto enargite deposit) and a porphyry copper-gold orebody (Far Southeast (FSE) deposit). Radiometric dating of the Victoria mineralization yields ages from 1.6 to 1.1 Ma, similar to ages of the Lepanto enargite deposit. Mineralogical, geochemical, fluid inclusion and sulfur isotope studies suggest that the Victoria deposit is not directly related to the late stage of hydrothermal activity that produced the FSE porphyry copper-gold and the Lepanto enargite deposits. The hydrothermal fluids from which Victoria was formed appear to have been derived from the south, and not from the FSE intrusive center to the northeast. This would suggest a regional south to north hydrothermal gradient, consistent with the similar flow within the FSE porphyry-Lepanto enargite system. On a district scale, structures similar to those of the Victoria deposit in trend and nature would be highly prospective, especially if they occur north of identified plutons and volcanic centers.

Evolution of Hydrothermal System at the Dizon Porphyry Cu-Au Deposit, Zambales, Philippines

“…Similarly, Arribas et al (1995) reported contemporaneous formation of the Lepanto-FSE porphyry Cu-Au deposit and the Lepanto high-sulfidation epithermal Cu-Au deposit (Garcia, 1991;Imai, 1999) at Mankayan district. In addition, the age of the Victoria low-sulfidation epithermal Au deposit (Claveria, 2001;Sajona et al, 2002) was also considered to be contemporaneous with Lepanto-FSE porphyry CuAu deposit and the Lepanto high-sulfidation epithermal Cu-Au deposit (Sajona et al, 2002).…”

Porphyry copper assessment of East and Southeast Asia: Philippines, Taiwan (Republic of China), Republic of Korea (South Korea), and Japan

“…5B). The polarity of subduction (west or east dipping) for the older arc is unknown, but it may be a northern extension of the Daguma Arc, which forms the older basement for the Cotabato Arc (appendix A) in Mindanao (Pubellier and others, 1991;Sajona andothers, 1997, 2000). The younger arc overprints the older arc and is also related to east-dipping subduction at the Negros Trench ( fig.…”

“…Postcollisional volcanic rocks vary from calc-alkalic (2.3-0.6 Ma) to shoshonitic (0.5-0.4 Ma) to calc-alkalic (0.3 to the present). The geochemistry of these rocks (OIB 7 -like enrichments in niobium (Nb), high La/Nb ratios) include typical arc as well as adakite-like compositions and may reflect contributions of upwelled mantle (Sajona andothers, 1997, 2000), possibly related to sinking of a detached slab of the Molucca Sea Plate 8 . Any porphyry systems are likely to be related to the pre-collisional rocks.…”

“…2A 6 ) represents an area of soft collision of two arcs in the Pliocene (4-5 Ma), followed by postcollisional calc-alkalic to shoshonitic magmatism (2-3 Ma) that produced the largest volcanic field in the Philippines (Pubellier andothers, 1991, 1996;Sajona andothers, 1997, 2000). Sajona and others (2000) noted that deep seismic studies refute a linkage with subduction along any of the trenches that surround Mindanao (Philippine Trench to the east, Sulu Trench to the west, or Cotabato Trench to the southwest, fig.…”

A Special Issue Devoted to Papers Presented at the International Symposium on Gold and Hydrothermal Systems, Fukuoka, Japan ‐ Postscript

“…Most locations are sites of newly discovered deposits or areas of under exploration, except for one abandoned, the Hoshino mine (Belhadi et al, 2002). Hishikari (Imai and Uto, 2002;Sekine et al, 2002;Etoh et al, 2002), Cikidang (Rosana and Matsueda, 2002) and Victoria (Sajona et al, 2002) already became operating mines. Presently exploration activities are being continued in Thorn (Awmack, 2002), Rodnikovoe (Takahashi et al, 2002), Cibaliung (Angeles et al, 2002), Francis Creek (Harijoko et al, 2002) and the north Xinjiang area (Qin et al, 2002), which were noticed in late 1980s to 1990s, and at Nena (Espi et al, 2002).…”