Detrital zircon geochronology and grain-size analysis of a similar to 2800Ma Mesoarchean proto-cratonic cover succession, Slave Province, Canada

Detrital zircon populations of five quartzite samples of the similar to 280 0 Ma Central Slave Cover Group, Slave Province, have been investigated to e xplore regional lithostratigraphic correlation/diachroneity. maximum deposi tional ages. ages of underlying basement, and general provenance issues. A total of 346 grains were analyzed by sensitive high resolution ion micropro be for U-Pb ages and by digital image analysis for grain size. Ages of indi vidual grains range from 3918 to 2808 Ma and define several important modes , notably at similar to 3400 Ma, 3150 Ma, 2950 Ma, and 2826 Ma. Although th e samples show significant differences, suggesting localized rather than we ll-mixed sediment provenances (supported by grain-size statistics), some mo des are shared among the samples in a pattern that supports regional correl ation. Nevertheless, the ages of the youngest detrital modes. in conjunctio n with independent age constraints from a parallel study, indicate either d iachroneity in the cessation of quartz arenite deposition across the realm of the Central Slave Cover Group or a difference in basement domains. (C) 2 001 Elsevier Science B.V. All rights reserved.