Data collected in the Port Wells mining district confidently show that the present structural features developed in several stages. These stages were folding, intrusion, faulting, and emplacement of quartz veins. The oldest stage was folding and concomitant metamorphism of the Cretaceous Valdez Group flysch during accretion. The semilithified rocks were folded in at least two phases. An early phase (F1) resulted in a 50% shortening in a northwest-southeast direction; the second phase (F2) caused minor shortening in a northeast-southwest direction. The next stage involved the intrusion of Oligocene plutons (36 m.y.) that crosscut earlier structures. Fracturing and faulting of the plutons and flysch characterized the next stage. Initial faults and structures caused only min r right-lateral displacement. The fault and joint data show details of the time relationship between intrusion and deformation. Several generations of epigenic gold-bearing quartz veins were emplaced along these joint systems. Minor deformation continuing to the present caused some disruption of the veins.

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