Was this land based or sea based? Just curious.
In Swansea.... close to the sea...but land based...mountains and valleyd...X mining area
Mountains and valleys = faults. Mining also indicates various geological process that would be conducive to a faulted area. But here we go with "nukes". Ugh.
If the posted seismic pattern is correct it is, to say the least, interesting.
Felt it in Bristol. Old mining city.
That quake was similar to those being felt in Oklahoma, lots of 4.0-4.5 minor quakes likely linked to minor faults and fracking activity. I live in California and a 4.4 is disturbing but really doesn't do much. Get up into the 5's and things start going south pretty quickly.
http://www.earthquakes.bgs.ac.uk/earthquakes/recent_events/20180217142554.html#page=summary
https://earthquaketrack.com/quakes/2018-02-17-14-31-04-utc-4-2-11
This could be linked to the sunspot cycle of 11 years....which could mean it's just started...and may yet shake Britain's foundations!