Metal deposits in relation to plate tectonics / Месторождения металлов в связи с тектоникой плит

Plate tectonics, as it operates in the modern earth, represents in a fundamental sense a mechanism by which excess thermal energy from the mantle is dissipated (Sclater et ai., 1980). A substantial data base now exists concerning the operation of plate tectonics during Phanerozoic time, and evidence for similar tectonic activity during Proterozoic time appears to be steadily growing, both in quantity and quality. Concrete evidence for the operation of plate tectonics during Archean time is simply not available, but provocative similarities exist between certain important elements of Archean terrains and the lithologic assemblages generated by certain types of modern plate interaction. Before we proceed further, the spectrum of tectonic activity that can be included under the rubric of plate tectonics requires clarification. In addition to large scale horizontal rotation of plates, aborted rifting, hotspot activity, and even Basin and Range-type extensional tectonics are all considered legitimate facets of plate tectonic activity. The last 200 million years of earth history can be rather rigorously interpreted in terms of plate interactions, thanks largely to interpretation and dating of seafloor magnetic anomaly patterns. Reconstructions of earlier plate interactions have to be made on the basis of the geologic record of the continents and paleomagnetic studies, but we need to remind ourselves that a considerable set of assumptions are involved in these exercises. Nevertheless, plate tectonic interpretations of more ancient continental geologic terrains appear to have met with considerable success in many instances, and exercises of this type continue apace <...>