The base of the silt is often an abrupt or erosive contact. At one site, the silt is clearly of post-European age, as shown by buried artifacts. Similar units elsewhere have been regarded by other workers as Post-Settlement Alluvium. However, the fluvial process resulting in the deposition of the orange-brown silt over all other units was diachronous. There has been continuing erosion of colluvium from hillslope to floodplain, from at least 3ka.
Modern entrenchment continues in the present in the distal parts of the terminal fan.
The cause of channel downcutting cannot, therefor, be due entirely to sudden post-European changes in hydrodynamic conditions. Other non-anthropogenic causes include increases in floodplain erodability by intrasedimentary evaporite precipitation, and entrenchment as part of the development of anabranches. All these processes are currently occurring in the Fowlers Creek system. This work is still in progress, and dates given above are subject to further refinement. Please note that these dates were obtained using a protocol that was specifically designed to deal with the problem of partial bleaching.