Moment magnitude scale ground motion measured by a particular type of seismometer (a Wood-Anderson seismograph) at a distance of from the earthquake's epicenter. Because of this, there is an upper limit on the highest measurable magnitude, and all large earthquakes will tend to have a local magnitude of around 7. Further, the magnitude becomes unreliable for measurements taken at a distance of more than about from the epicenter. Since this scale was simple to use and corresponded well with the damage which was observed, it was extremely useful for engineering earthquake-resistant structures, and gained common acceptance. The Richter scale was not effective for
Frankston, Victoria in or near the suburb of Frankston have occurred in 1932, 1978, 1980, 2009 and 2014. The most recent, on 15 March 2014, measured 2.2 on the Richter magnitude scale. The largest, on 22 September 2009, measured 3.0 on the Richter scale. Olivers Hill is the most prominent elevation in Frankston which rises to 55 metres above sea level (180 feet) at its highest point in the suburb. Its origins date to approximately 415 to 360 million years ago. Its base is Mount Eliza Granite dating from the Devonian period, which was covered in lava tuffs in the Paleogene period.