It will almost certainly take several tens of thousands of years, if the growth rate for L'ihi is comparable to that of other Hawaiian volcanoes (about 0.1 foot per year averaged over geologic time).
A: The Richter scale is used to quantitatively measure the magnitude of an earthquake. This tool was devised by the seismologist Charles F. Richter in 1935. Full Answer >
The magnitude of an earthquake is a Logarithmic scale. The famous Richter Scale uses this formula: M = log 10 A + B. Where A is the amplitude (in mm) measured by the Seismograph. and B is a distance correction factor. Nowadays there are more complicated formulas, but they still use a logarithmic scale.