Timing and origin of megabreccia and folds along the Early Middle Cambrian margin of the Georgina Basin, Australia

Feltrin, Leonardo, and Oliver, Nicholas H.S. (2014) Timing and origin of megabreccia and folds along the Early Middle Cambrian margin of the Georgina Basin, Australia. Carbonates and Evaporites, 29 (1). pp. 3-31.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1007/s13146-014-019...
 
2
1


Abstract

Megabreccia and related folds are two of the most interesting features of the Lawn Hill Outlier, a small carbonate platform situated in the northeastern part of the Georgina Basin in Queensland, Australia. Field studies and stable isotopic data were used to assess the timing and origin of folds and megabreccias in this carbonate plateau, and understand its possible relationship to an asteroid impact. Together with field and isotope data, the reconstruction of the sequence of events that led to the cratonization of the Centralian Superbasin supports a synsedimentary timing of formation for the folds and breccias. Some of the brittle faulting and veining accompanying strain localisation within the Thorntonia Limestones may represent, however, post-sedimentary, syntectonic deformation, possibly linked to the Late Devonian Alice Springs Orogeny. An origin for the folding and megabreccias linked to an asteroid impact cannot be completely discounted. Nevertheless, observed field relationships concerning the spatial distribution and typology of breccias occurring in basement and cover agree with stable isotopic signatures, suggesting that multiple intrabasinal processes contributed to platform destabilisation. Processes such as karstification, solution collapse, and fault reactivation, were the most likely mechanisms responsible for the formation of intrastratal breccias and slump folds in the Lawn Hill Outlier.

Item ID: 33157
Item Type: Article (Research - C1)
ISSN: 1878-5212
Keywords: Lawn Hill Outlier, megabreccia, Century deposit, dikes, debris-flow, slumps
Date Deposited: 14 May 2014 09:46
Downloads: Total: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page