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 Richter scale for earthquake measurements is logarithmic. This means that each whole number step represents a ten-fold increase in measured amplitude. Thus, a magnitude 7 earthquake is 10 times larger than a 6, 100 times larger than a magnitude 5 and 1000 times as large as a 4 magnitude.