Hypo-theses

The swarm of earthquakes in north Leicestershire / south Nottinghamshire continues with another magnitude 2.5 event, again recorded here at Keele.

So far there have been several events in the sequence, a couple of previous ones recorded at Keele are in a previous post.

Here is the current list from the BGS
2013/02/27 23:57:01.9 52.900 -1.038 7 2.5 NOTTINGHAM,NOTTS FELT LONG EATON…
2013/02/04 10:51:59.0 52.748 -1.044 2 2.4 LOUGHBOROUGH,LEICS FELT LOUGHBOROUGH
2013/02/04 10:51:56.8 52.748 -1.044 2 1.6 LOUGHBOROUGH,LEICS
2013/01/21 11:40:04.1 52.800 -1.257 11 1.4 LOUGHBOROUGH,LEICS FELT LOUGHBOROUGH
2013/01/18 05:20:44.4 52.801 -1.250 13 2.9 LOUGHBOROUGH,LEICS FELT LOUGHBOROUGH…

A couple of recent UK Midlands earthquakes near Loughborough, Leicestershire. The main shock, magnitude 2.9 (above) occurred at 05:20:44 on January 18 and a magnitude 1.3 aftershock (below) at 11:40:04 on January 21, 2013. The first event was widely felt over a 25km radius, with some reports over 50km away.

At 13km depth these are natural earthquakes (with no added fracking involvement). Whilst I am loathed to ascribe UK intraplate seismicity to particular tectonic features, these events would approximately accord with the north eastern margin of the Midlands Microcraton.

More details from the BGS.
January 18
January 21

Earthquake, 2012-12-07 08:18:24 magnitude 7.3 off east coast of Honshu, Japan with small tsunami. Earthquake record from Keele, UK.

More details from the USGS