I understand that the REALLY BIG quakes happen along the fault lines. For example;
- Indonesia has a plate/fault line to its South
- Japan has a number of plates to the east
- North America has a fault line right down the Western Seaboard.
- fault line virtually under Christchurch, and down the eastern side of NZ
- Himalayas are a result of 2 plates pushing together, and pushing up.
I'm just saying that basically any quake around Sydney at 8.0+ would be extremely unlikely.
Newcastle's quake in 1989 was about 5.6, and even though it did a reasonable amount of damage, its because Newcastle was not built to withstand quakes.
Gippsalnd Victoria has also had some "strong" earthquakes lately. "Strong" for them and Melbourne folk, at circa 5.2 or 5.4... in that ball-park anyway.
I've felt 5's in Japan. Realistically, they are just a fun little wake-up call, time to disco!
If you're on the beers, you would lean over to your mate and say, "Wow these beers are really hitting the spot today, they are rocking my world!"....
However, a big/decent quake between the Pacific Plate and Australian Plate should be considered as "likely", at some point over the next few years. But, many quakes don't create a tsunami, plus this fault line is mostly 2000-3000km away from Australia. And the effects of a "tidal wave" would be greatly reduced by the time it arrived.
I understand that Eastern Australia has had almost no tsunami activity in history, however I remember a guy telling me about some geology research in The Flinders Islands near Tassie, and that there is records of some dirty big boulders from the sea shore sitting a reasonable distance up the hills, and suggestions that a decent tsunami event put them there !!
