Displaying items by tag: volcanic diatreme

In November last year STEP held a talk by Dr Ian Percival on the unique volcanic diatreme that has been exposed in the Hornsby Quarry. The Geological Society of Australia and STEP made submissions to the Roads and Maritime Services about the project to use the quarry void to dispose of spoil from the NorthConnex tunnel. But while it appears that the upper two levels of the quarry will escape burial, so far we have seen little reference in any document to the enormous importance of this site as a scientific and educational tool.