Early Cretaceous adakite from the Atlas porphyry Cu-Au deposit in Cebu Island, Central Philippines: Partial melting of subducted oceanic crust

In the Philippine island arc system, there are widely developed Cenozoic arc volcanic rocks, adakites and large Cu-Au deposits. Besides, only two early Cretaceous adakitic intrusions have been found in the entire Philippines so far, i.e., the Lutopan Diorite and the adjacent Kansi diorites in Cebu Island, Central Philippines. The Lutopan Diorite (diorite to quartz diorite in lithology) is the ore-forming intrusion of the giant Atlas porphyry...