Characteristics of the Kematu epithermal gold deposit at Tboli, Mindanao, Philippines

• DOI: 10.1111/rge.12339
• Publication Date: 2024-10-02T03:16:24Z
• Authors: Alan Royce B. Tizon; Jillian Aira S. G...; Pearlyn Manalo; Ryohei Takahashi; Ma. Yna Rose D. G...; Juan Alex Vianne ...

Abstract The Kematu Au‐Ag epithermal deposit at Tboli area, Province of South Cotabato, Mindanao, Philippines, contains an inferred mineral resource 3.8 million tonnes, 8.7 g/t Au and 27 Ag in 2012. is spatially genetically linked to the volcanism related Parker Volcanic Complex Pliocene Holocene age. Local extension northwest‐trending splays faults area are associated with mineralization, including deposit. study aimed provide a detailed description characteristics physicochemical processes involved formation on basis field occurrence, mineralogy, ore composition, chemistry, sulfur isotope data. characterized by bearing quartz‐adularia‐clay‐sulfide veins hosted argillic‐altered andesite porphyry coarse tuff Complex. mineralization form as well open space fill dissemination. Based observation bodies petrographic analysis, three paragenetic stages different vein have been identified. Stage 1 dominantly quartz, adularia, clay veins, electrum, sphalerite, pyrite, chalcopyrite, tetrahedrite‐tennantite, galena. 2 coarse‐grained sulfide‐quartz‐adularia in‐fill vugs, consisting galena, electrum. 3 massive calcite minor amounts alteration assemblage host rocks chlorite‐illite‐adularia, indicative neutral pH conditions. FeS content Fe‐poor sphalerite stage ranges from 0.03 1.07 mol%. Sulfur compositions (δ 34 S CDT ) sulfides all range 0.1‰ 1.9‰ for −5.3‰ 0.5‰ where those tend relatively lower values compared 3. narrow close zero δ suggest that was mainly derived magma. assemblages 1, 2, 3, fugacity (log f = −12.5 −8.8) temperature (200–280°C) based mol%, electrum composition (at.%), intermediate sulfidation type.