The profile of an alluvial soil found in the McHugh's Gully. This soil is poorly structured and has poor cohesion. It breaks down easily in water. Evidence of tunnelling along tree roots can be seen on the right. Below the narrow A and B horizons is the deep C horizon, the alluvium on which the top soil has formed. The quartz gravel at the base of the slide indicates its fluvial origin. The source rock came from Ordovician hills surrounding the gully. |