Far Southeast-lepanto Porphyry-Epithermal Cu-Au Deposits, Philippines: Coupled Hydrothermal Processes Between the Porphyry and High-Sulphidation Environments

摘要

The spatial and temporal evolution from the porphyry to high-sulphidation epithermal environment can be assessed by integrating new reuslts on such deposits (Arribas et al, 1995; Hedenquist et al, 1998) with past stuides of plutonic and porphyry systems (Dilles and Proffett, 1995; Cline, 1995; Shinohara and Hedenquist, 1997; Hedenquist and Richards, 1998). Some time ago, Sillitoe (1973) argued fo rthe nature of the tops and bottoms of porphyry deposits. He concluded that epithermal deposits may form over the tops of some porphyry systems. We can now conclude more confiently what the tops and bottoms of may high-sulphidation ore deposits appeared like while active (Arribas, 1995; Hedenquist, 1995). In addition, we better understand the nature of the zonation of high-suphidation epithermal systems fromthe intrusive to surficial environment (Sillitoe, 1999), and how these two styles of ore deposit are related. Geological and geochemcial evidence clearly indicates a continuum between these two ore environments. This improved understanding of genesis allows more efficient exploration for these deposits.