Periodicity and kinematics of the formation of porphyry copper deposits in the pacific belt over the past 125 million years

Statistical analysis of the time series of Cu-porphyry deposits of the Pacific belt and their total ore volume formed in the last 125 million years showed the presence of (quasi)a cyclic component with a period of 26–28 million years, whose share in the total amplitude is 74%. An inverse correlation has been established between the global spreading rate, on the one hand, and the number of Cu-porphyry deposits in the Pacific belt and their productivity, on the other, for the last 125 million years. The relative minima of the spreading rate precede the relative maxima of the number and total volume of Cu-porphyry deposits in the Pacific belt by 5–10 million years. During the formation of large and giant Cu-porphyry deposits in the Pacific belt, the rate of change in the angle of convergence in the horizontal plane in the zone of interaction between two tectonic plates increases. At the same time, the absolute rate of convergence can both decrease and increase. According to geological, structural and kinematic data, magmatism, as a result of which 8 large and giant Cu-porphyry deposits were formed, was accompanied by through-crust disjunctive disturbances associated either with a change in the frontal convergence of the "oblique", or a transition to the mode of a transform continental margin, or with a reversible change in the direction of subduction associated with the island arc-continent collision The island arc is an oceanic plateau.