Crust mantle decoupling and the growth of the Archaean Zimbabwe craton
Abstract
Based on the Zimbabwe craton, it is suggested that, during the Archaean, full decoupling between a strong upper crust and a strong upper mantle across a weak detachment zone at the Moho allowed the independent development of crustal and mantle geometries in response to lithospheric shortening. This is an effective way to explain the field observations made in the Zimbabwe craton, which suggest a late-Archaean interplay between lateral accretionary processes through low angle thrust stacking and underplating and deep seated lineament zones with a possible mantle origin. The lineament zones play an important role in the localisation of mineral deposits such as base metals, gold, and possibly diamonds. Thickening of the mantle lithosphere occurred independently from the crust, through early Archaean melt segregation and/or lithospheric underplating.
- Publication:
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Journal of African Earth Sciences
- Pub Date:
- May 2002
- DOI:
- 10.1016/S0899-5362(02)00015-5
- Bibcode:
- 2002JAfES..34..157D