2007 Kent earthquake earthquake in 1950. The strongest recorded British earthquake is the 1931 Dogger Bank earthquake, which measured 6.1 on the Richter scale. Ten months later, the earthquake's strength was surpassed by that of the 2008 Lincolnshire earthquake, which was 5.2 in magnitude. Less than two years later, on 3 March 2009 at 14.35 UTC, Folkestone was shaken by a smaller magnitude 3.0 quake, located in the same area. 2007 Kent earthquake The 2007 Kent earthquake registered 4.3 on the Richter scale and struck south east Kent, South East England on 28 April 2007 at 07:18:12 UTC (08:18:12 local time), at a
Seismic magnitude scales times. As originally defined by m was based on the maximum amplitude of waves in the first 10 seconds or more. However, the length of the period influences the magnitude obtained. Early USGS/NEIC practice was to measure on the first second (just the first few P-waves), but since 1978 they measure the first twenty seconds. The modern practice is to measure short-period scale at less than three seconds, while the broadband scale is measured at periods of up to 30 seconds. The regional mb scale – also denoted mb_Lg, mbLg, MLg (USGS), Mn, and m – was developed by for