Trentham Falls
S 37° 22.228 E 144° 19.485
55H E 263103 N 5860670
A waterfall where the Coliban River cascades over columnar bassalt cliffs near Trentham, Victoria.
Waymark Code: WM7PZ
Location: Victoria, Australia
Date Posted: 02/17/2006
Views: 65
Some five million years ago the old Coliban River flowed through a picturesque gully lined with blackwood forest.
One day this environment was shattered and burnt as a wall of molten lava advanced northwards from a small volcano to the south, completely filling the gully.
Remains of the timber and even a platypus skull have been found in the silty ash beneath the rock face.
The lava cooled very slowly and, as it solidified, contraction caused vertical cracking, creating columns.
The present Coliban River has eroded by back-cutting. Once the falls were further downstream but undercutting and collapses have shifted them to their present position.
Basalt columns and whole sections of rock face collapse as spray undercuts soft river sediments.
In the near future, the area that forms the current waterfall in these pictures is expected to fall. Tell-tale signs of this can be seen in water seepages and widening cracks.
Already some large blocks have fallen reminding us that this erosion is an ongoing and natural process.