1. Syntectonic Late Devonian terrestrial sedimentation in the southern Bonaparte Basin, Western Australia.
- Author
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Jones, Brian G.
- Subjects
- *
BRAIDED rivers , *ALLUVIAL fans , *ALLUVIUM , *SEDIMENTATION & deposition , *TOPOGRAPHY - Abstract
Late Devonian sedimentation in the southern Bonaparte Basin was controlled by, and provides a record of, contemporaneous fault movements in the Halls Creek Orogen. An important episode of Late Devonian faulting caused uplift and southward tilting of the Carr Boyd Ranges block and uplift and northward tilting of the O'Donnell Ranges block forming the Galloping Creek and Ragged Ranges sub-basins, respectively. Uplift of the Carr Boyd Ranges provided the eastern source of the Ragged Range Conglomerate, while the south-dipping Carr Boyd Ranges and the uplifted O'Donnell Ranges and Bow River blocks formed the northern and western sources of the Galloping Creek Formation. Conglomeratic facies on both the northern and southwestern margins of the Galloping Creek Sub-basin record interaction with a fault-controlled topography. The apparent lack of unconformities within the northern Galloping Creek Formation and the progressive increase in siltstone content towards the centre of the sub-basin suggest that faulting was no longer an active driver for sedimentation. While alluvial fan deposition infilled the southwestern part of the sub-basin, the remainder of the Galloping Creek Formation was deposited by fluvial systems that changed from an initial proximal braided stream character to a later distal character with more extensive floodplain deposition. Post-depositional folding and faulting of the Galloping Creek Sub-basin were confined to movement on the Halls Creek and Glenhill faults with a probable 10+ km of sinistral offset and uplift of the western block along at least the latter. KEY POINTS: Late Devonian fluvial sedimentation in fault-initiated sub-basins of the southern Bonaparte Basin, Western Australia. Faults were active during Ragged Range Conglomerate deposition, but movement ceased during Galloping Creek Formation deposition. Galloping Creek Formation shows upward fining away from the sub-basin margins. Few faults were reactivated after Frasnian deposition. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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