Mittagong Formation
Appearance
Mittagong Formation | |
---|---|
Stratigraphic range: | |
Type | Geological formation |
Underlies | Ashfield Shale |
Overlies | Hawkesbury sandstone |
Thickness | up to 10 metres (30 ft) |
Location | |
Location | Sydney Basin |
Country | Australia |
Type section | |
Region | Mittagong |
Country | Australia |
Thickness at type section | 15 metres |
The Mittagong Formation is a sedimentary rock unit in the Sydney Basin in eastern Australia.[1]
Formation
[edit]Laid down in the Triassic Period, it may be seen as an interval of interbedded fine-grained sandstone and shale between the Ashfield Shale (above) and the Hawkesbury sandstone (below). The maximum thickness around Sydney may be ten metres.[2] Near Town Hall railway station, the formation is 8 metres thick. In the type area at Mittagong it is 15 metres thick.
Whereabouts
[edit]In northern Sydney it can be seen in several areas, such as West Pymble[3] and Mount Ku-ring-gai.[4] This rock formation is associated with the critically endangered Sydney Turpentine-Ironbark Forest.[5]
See also
[edit]References
[edit]- ^ "Australian Museum - The Sydney Basin".
- ^ "Geoscience Australia".
- ^ Field Geology of New South Wales, Sydney Basin page 102
- ^ Chris Herbert. Geology of the Sydney 1:100,000 Sheet 9130
- ^ "Sydney Turpentine-Ironbark Forest".