rhyodacitic ignimbrite, sandstone, siltstone and red and yellow shale. Southwards the section passes up into a massive and partly banded rhyodacitic ignimbrite. The bottom of the Deakin Volcanics is exposed on nearby Heysen Street. At least 400m thickness of beds are exposed in the Parkway cutting. The Tuggeranong area has the thickest deposits. Rock types in the Deakin Volcanics are rhyodacitic ignimbrite, lava (Mugga Mugga Porphyry Member), tuff, tuffaceous shale and minor quartz sandstones and volcanic breccia-units show reddish brown alteration. The unit is of Early Ludlovian age.