Unusual earthquake along the coast of Wales, United Kingdom

Last update: May 29, 2013 at 10:29 am by By Ashish Khanal

Update 09:10 UTC : In a statement BGS reports:

The earthquake of the 29 May 2013 occurred at 03:16 UTC (04:16 BST), with an epicentre approximately 13 km NW of Abersoch, Gwynedd. The instrumental magnitude was determined at 3.8 ML, and the earthquake was located approximately 21 km WSW of the magnitude 5.4 earthquake that occurred on 19 July 1984 (a magnitude of 3.8 is approximately 256 times smaller than 5.4). The estimated area over which an earthquake with a magnitude of 3.8, and depth of 8 km, would be felt was calculated to be a distance of up to 75-100 km from the epicentre (at intensity 3 EMS). Analysis of the results from an automatic online questionnaire survey agrees with this. Almost 100 felt reports have been received. Of those, almost all of them came from within a 50 km radius, from Abersoch, Caernarfon, Bangor, Holyhead and their surrounding hamlets. Reports generated in a north-easterly direction from the epicentre. A little further afield, reports were received from Conwy and Rhyl area (75-100 km to NE of epicentre), whilst single reports were received from Southport, Merseyside (140 km to NE of epicentre), the Isle of Man (140 km to north of epicentre). There are also reports of the earthquake having been felt on the east coast of Ireland (110 km east of epicentre).

Most people described having been awoken from their sleep by the moderate shaking strength of the earthquake, which had a trembling effect. The sound strength was also described as moderate. Many of the reports stated that windows and crockery rattled. Reports described “the bed was shaking too scared to look at anything else”, “loud rumbling sound woke me, then noticed s sound of mirror rattling on bedside cabinet”, “gradually grew louder. Classic underground train passing sensation“ and “woke the household any many neighbours”

Update 08:42 UTC : This great image goes viral on twitter as being the damage triggered by the Wales earthquake. Welsh great humor !

Damage in Wales – Twitter image courtesy @Leighsheps

Update 07:55 UTC : As expected we have not found 1 single report of damage so far, a report which we like a lot . If you have any knowledge of damage near the epicenter, even cracks in walls, please let us know.
– Geofon Germany just comes up with a Magnitude of 4.3.
– Seismology is a very difficult science and data may differ a lot according to the reporting seismological agency. Earthquake-Report.com values to local data always as “probably” the most accurate simply because the local agencies have the most instruments closest to the epicenter. The world press seems to think that USGS is the God of seismology. We favor more USGS as one of the Gods and a very good one .

Update 04:55 UTC : We have now a report from BGS (British Geological Survey) mentioning a Ml Magnitude of 3.8 at a depth of 8 km. As earthquake location is mentioned Lleyn peninsula (epicenter is the green arrow).  The villages of Pennlech and Porth Colmon are closest to the epicenter. Based on these (to be trusted) data, the chance of even minor damage has been decreased.

Update 04:42 UTC : We assume that most Welsh journalists haven’t felt it as there are NO reports so far in the local press (at least not the many we have consulted).

Update 04:35 UTC : Based on what we are reading from the many I Have Felt It reports below, we expect some minor damage on the nearby Wales peninsula. Minor damage means in this case fallen objects, cracks in older walls, fissures or even collapsing chimneys, fallen roof tiles, etc. We do not expect injuries. The damage, if any, would have been proportionally bigger with an epicenter below land.

Update 04:28 UTC : Only EMSC has reported this earthquake. The local British Geological Survey hasn’t even mentioned it in his website. The last significant earthquake in the United Kingdom happened in Market Rasen, Lincs, on February 27 2008. That one was more powerful at M5.2.

Update 04:12 UTC : EMSC has shifted the location of the epicenter more into the Irish Sea, weakening that way the impact of this earthquake.
As you can see on our bottom map, nothing important occurred in the area since 1900.

This earthquake was initially reported by EMSC as a M5.5 earthquake, which would surely have been damaging. But even at the current still preliminary value of M4.3, we can speak of an unusual strong earthquake for the United Kingdom.

The coastal area of Nefyn Bay, closest to the epicenter – Image courtesy John Goodall

90 km SE of Dublin, Ireland / pop: 1,024,027 / local time: 04:16:26.0 2013-05-29
59 km SW of Caernarfon, United Kingdom / pop: 9,836 / local time: 04:16:26.0 2013-05-29
44 km W of Pwllheli, United Kingdom / pop: 3,904 / local time: 04:16:26.0 2013-05-29

Most important Earthquake Data:

Magnitude : 4

Local Time (conversion only below land) : 2013-05-29 04:16:29

GMT/UTC Time : 2013-05-29 03:16:29

from:    http://earthquake-report.com/2013/05/29/strong-earthquake-wales-united-kingdom-on-may-29-2013/