Events in the Precambrian history of the earth : challenges in discriminating their global significance

Abstract

This paper discusses geological events with an approximately global preservational scale which can aid inter-cratonic correlations and contribute to postulates of supercontinents for a set of chosen Precambrian cratons. The chronological scale of such events is highly variable, and most event types detailed (supercontinent-, mantle plume-, orogenic-, chemostratigraphic-, glacial events and major unconformities) have durations concomitant with the large-scale interaction of mantle thermal and plate tectonic processes that were largely responsible for their genesis, i.e. 10s to 100s of millions of years. Geologically instantaneous events of global compass (e.g., impact or major eruptive events) provide important chronological markers for interpreting the longer term events. The same interplay of tectono-thermal geodynamic processes that drives the evolution of the Earth and the operation of its supercontinent cycles is also, ultimately, responsible for and of comparable duration to first- and second-order sequence stratigraphic cyclicity. This paper thus serves to introduce these concepts and discuss the problems in their application to specific Precambrian cratons, in relation to the aim of this special issue, of providing a set of accommodation curves for many of these ancient crustal terranes.