Tectonics-mineralisation relationships within weak continental lithospheres: a new structural framework for Precambrian cratons

Abstract

Many Archaean and Paleoproterozoic cratons show deformation patterns that differ from those observed in modern orogens. On the other hand, they constitute an important part of present-day emerged continents and contain a large part of continental mineral resources known to date. On the basis of a summary of structural data from some typical field examples and of results of analogue modelling, we emphasize that pop-down tectonics marked by vertical burial of supracrustals within an underlying hot and weak crust may be the most suitable model to account for deformation patterns of many ancient deformation zones. An overview of relationships between structural patterns and mineralisation in several ancient deformation zones further emphasizes that pop-down tectonics provides a very promising structural framework for mining exploration in Precambrian cratons.