Magnitude 2.6 Earthquake in Hucknall, Nottinghamshire.
Struck at 7:16pm GMT, 28th October 2014.
A magnitude 2.6 earthquake has struck approximately 11 kilometres north of Nottingham. Felt in Nottingham, Carlton, Hucknall and Mansfield. No aftershocks have been observed and few if any are expected. This does not however rule out the potential for a larger or similar size earthquake.
Update 10:04 GMT, 29th October:
This morning BGS released most of its information on yesterday evening's magnitude 2.6 earthquake just north of Hucknall, Nottinghamshire. It struck at 7:16:54pm and had a focal depth of 7.1 kilometres. Many felt reports were given to BGS, most centred in Hucknall, Kirkby in Ashfield, Sutton-in-Ashfield, Mansfield, Ravenshead and north-east Nottingham. The furthest felt report was from south-west Nottingham, some 15 kilometres (10 miles) away.
BGS also released it's customary historical seismicity map for the earthquake. This shows three significant quakes in the region in the past 250 years, with M4.7 & M4.2 events in 1795 & 1816 respectively, whilst in more recent times a magnitude 4.1 earthquake struck south-east of Nottingham.
BGS says this is the largest earthquake to hit Nottinghamshire since March 1984 (M3.2, East Retford). This is very puzzling as a large earthquake of ~M3.6 was recorded in east Mansfield in February 1990 by the United States Geological Survey (USGS); it is entirely doubtful that USGS overestimated the magnitude of this earthquake by such a large amount so that BGS recorded the 1990 quake as less than M2.6.
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| A map of BGS felt reports to the M2.6 Hucknall Earthquake on the 28th October 2014. All rights to BGS. |
BGS also released it's customary historical seismicity map for the earthquake. This shows three significant quakes in the region in the past 250 years, with M4.7 & M4.2 events in 1795 & 1816 respectively, whilst in more recent times a magnitude 4.1 earthquake struck south-east of Nottingham.
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| A map of historical and instrumental seismicity around the Mansfield and Nottingham area. The ~M3.6 Mansfield Quake of 1990 can be seen as the moderate-sized red circle just south-east of Mansfield. |
BGS says this is the largest earthquake to hit Nottinghamshire since March 1984 (M3.2, East Retford). This is very puzzling as a large earthquake of ~M3.6 was recorded in east Mansfield in February 1990 by the United States Geological Survey (USGS); it is entirely doubtful that USGS overestimated the magnitude of this earthquake by such a large amount so that BGS recorded the 1990 quake as less than M2.6.
If you have any queries or comments about this earthquake or my website, please send correspondences to: sincalveniren@ymail.com
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| The BGS seismometer station at Charnwood Forest, Leicestshire. The M2.6 Hucknall Earthquake is clearly visible on the 19:00 UTC line - it arrived at Charnwood Forest about 6 seconds after the earthquake began. |
7:56PM Two tweets have been found thus far regarding the minor tremor (https://twitter.com/leemarch/status/527184827792232449 & https://twitter.com/steviemac2010/status/527178392022843392).
As of 8:00pm BGS has not put up the earthquake, nor has EMSC noted it.
8:11PM - CEA's magnitude has an uncertainty of ~0.27 magnitude, so magnitude of the earthquake is currently between M3.0 and M3.6. No news agencies picked up quakes, although an editor at Sky has noted the increase in twitter activity (https://twitter.com/SkyNewsEditor/status/527189157228335105)
8:22PM - Both BGS & the Nottingham Post have reported the earthquake being felt in and around Nottingham. BGS is currently working on analysing the earthquake. Very sketchy talk of it being either an earthquake or gas explosion. No word yet from main news agencies in the UK (ITV, BBC or Sky).
8:51PM - BGS has given an official magnitude of 2.6 to this tremor, much smaller than CEA's preliminary magnitude 3.3. This is extremely normal, the French Agency commonly overestimating magnitudes of British earthquakes. Below is a picture of the locations of the earthquake according to CEA & BGS respectively.
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| Location of earthquake according to BGS (British Geological Survey) & CEA (French Agency). BGS location & magnitude much more reliable/ |
9:00PM - EMSC quotes BGS data on their website, completing the list of agencies expected to report the Mansfield Earthquake (or Hucknall Earthquake as would appear to be more accurate - see above map!!). BGS say the earthquake had an observed intensity of 3 on the European Macroseismic Scale which seems consistent with reports by people on Twitter over the past two hours.
10:04PM - A look at the archives reveals that there has been relatively few felt earthquakes in the past 25 years. The largest earthquake in the region in that time was a magnitude 3.6 earthquake which hit Mansfield in February 1990. The only other magnitude 2+ earthquake nearby since 2000 was a magnitude 2.5 tremor that struck just south of Cotgrave, near Cropwell Bishop, in February 2013. This earthquake was felt over a reasonable area, with reports coming in via BGS from many local villages and the town of Hucknall, whilst other reports have come from Carlton in East Nottingham & the village of Mapperley west of Nottingham.
Sources:
BGS: http://www.earthquakes.bgs.ac.uk/earthquakes/recent_events/20141028191600.html#page=summary
CEA: http://www-dase.cea.fr/evenement/evenements.php?type=seisme&identifiant=20141028-191657&lang=en
EMSC: http://www.emsc-csem.org/Earthquake/earthquake.php?id=406145
This article was written on the 28th October 2014 by J H Gurney
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