The 1990 Bishop's Castle earthquake occurred near the town of

Bishop's Castle Bishop's Castle is a market town in the south west of Shropshire, England. According to the 2011 Census it had a population of 1,893. Bishop's Castle is east of the Wales-England border, about north-west of Ludlow and about south-west of ...

Shropshire Shropshire (; alternatively Salop; abbreviated in print only as Shrops; demonym Salopian ) is a landlocked historic county in the West Midlands region of England. It is bordered by Wales to the west and the English counties of Cheshire to th ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

on 2 April.

Location, date and time

On 2 April 1990, a powerful earth tremor was felt across much of

and

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

at 13:46 34.2s

GMT Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London, counted from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a cons ...

. Early news reports in the immediate aftermath speculatively attributed the epicentre to places as far apart as

Nottingham Nottingham ( , East Midlands English, locally ) is a city status in the United Kingdom, city and Unitary authorities of England, unitary authority area in Nottinghamshire, East Midlands, England. It is located north-west of London, south-east ...

and a valley in the east of

and then settled on

Wrexham Wrexham ( ; cy, Wrecsam; ) is a city and the administrative centre of Wrexham County Borough in Wales. It is located between the Welsh mountains and the lower Dee Valley, near the border with Cheshire in England. Historically in the count ...

, before geologists finally concluded that it had in fact been in the vicinity of the small town of

Clun Clun ( cy, Colunwy) is a town in south west Shropshire, England, and the Shropshire Hills Area of Outstanding Natural Beauty. The 2011 census recorded 680 people living in the town.Combined populations for the two output areas covering the tow ...

near the town of

Cause

Bishops Castle lies atop an ancient geological fault line – the Pontesford-Linley fault. A sudden movement in the fault sent shock waves through the rock. The local rocks are predominantly

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

Middle Lias.

Magnitude

The magnitude of the earthquake was originally measured as being between 4.9 and 5.4 on the

Richter scale The Richter scale —also called the Richter magnitude scale, Richter's magnitude scale, and the Gutenberg–Richter scale—is a measure of the strength of earthquakes, developed by Charles Francis Richter and presented in his landmark 1935 ...

. Its final estimated magnitude was 5.1, which meant that it was the strongest earthquake to have struck the UK since the 1984 Llŷn Peninsula earthquake.

Impact

The earthquake was felt by people as far away as the east of the

Republic of Ireland Ireland ( ga, Éire ), also known as the Republic of Ireland (), is a country in north-western Europe consisting of 26 of the 32 counties of the island of Ireland. The capital and largest city is Dublin, on the eastern side of the island. A ...

to the west, the city of

Newcastle upon Tyne Newcastle upon Tyne ( RP: , ), or simply Newcastle, is a city and metropolitan borough in Tyne and Wear, England. The city is located on the River Tyne's northern bank and forms the largest part of the Tyneside built-up area. Newcastle is ...

to the north-east, the county of

Kent Kent is a county in South East England and one of the home counties. It borders Greater London to the north-west, Surrey to the west and East Sussex to the south-west, and Essex to the north across the estuary of the River Thames; it faces ...

to the south-east, and the county of

Cornwall Cornwall (; kw, Kernow ) is a historic county and ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people. Cornwall is bordered to the north and west by the Atlantic ...

to the south-west. In

Shrewsbury Shrewsbury ( , also ) is a market town, civil parish, and the county town of Shropshire, England, on the River Severn, north-west of London; at the 2021 census, it had a population of 76,782. The town's name can be pronounced as either 'Sh ...

, the county town of

, which lies approximately 20 miles to the north-east of

, there was damage to masonry, with a number of chimney stacks being broken off from roofs and collapsing partially or completely into gardens and streets. Some others were knocked askew. Several of the worst affected buildings, including shops, were evacuated. Police cordons were put up around houses at risk of chimney-collapse until they had been made safe, with at least fifty properties in the town reported as requiring emergency attention within the twenty-four hours immediately following the event, while others requiring less urgent treatment were tended to on subsequent days. There was also damage to ornamental features such as crosses and gargoyles built into the masonry of some of

's medieval churches, and to

Clun Castle Clun Castle is a medieval ruined castle in Clun, Shropshire, England. Clun Castle was established by the Norman lord Robert de Say after the Norman invasion of England and went on to become an important Marcher lord castle in the 12th century, ...

. Electrical power was lost from areas served by some substations situated approximately thirty kilometres (seventeen miles) from the epicentre after the earthquake caused transformers at the substations to trip offline. Residents of the worst affected areas, including parts of

, reported lateral shaking and swaying to the walls of their houses at the height of the tremor, which was preceded and then accompanied by a rumbling noise that gained strength over a period of 15 to 30 seconds before reaching and sustaining peak intensity during the most severe shaking. Finally, the movement and accompanying sound tailed off much more rapidly than it had first built up, stopping altogether within just a few seconds from the peak activity. Damage to buildings was also reported in

, and some minor damage as far north as

Liverpool Liverpool is a city and metropolitan borough in Merseyside, England. With a population of in 2019, it is the 10th largest English district by population and its metropolitan area is the fifth largest in the United Kingdom, with a popul ...

and

Manchester Manchester () is a city in Greater Manchester, England. It had a population of 552,000 in 2021. It is bordered by the Cheshire Plain to the south, the Pennines to the north and east, and the neighbouring city of Salford to the west. The t ...

. No serious injuries were reported. An engineering consultant, using the 1990 Bishop's Castle earthquake specifications as a model, has estimated that the slightly weaker

2002 Dudley earthquake __NOTOC__ The following is a list of notable earthquakes that have affected the British Isles. On average, several hundred earthquakes are detected by the British Geological Survey each year, but almost all are far too faint to be felt by humans ...

measuring 4.8 on the

would have caused structural damage of an order costing less than 5% of the cost of the complete reconstruction of an entire property to repair, to 1% of buildings situated in towns in the vicinity of the epicentre. While some indication of the typical percentage of homes damaged to a similarly minor extent by a slightly stronger earthquake measuring 5.1 on the

may be extrapolated from this estimation, a representative of the

British Geological Survey The British Geological Survey (BGS) is a partly publicly funded body which aims to advance geoscientific knowledge of the United Kingdom landmass and its continental shelf by means of systematic surveying, monitoring and research. The BGS h ...

has stated that 'numerous' but fewer than 20% of properties in Shrewsbury suffered the partial or total loss of their chimneys or damage of equivalent gravity ''(see below)''. Reliable, exact figures of the percentage of buildings damaged close to the epicentre of the 1990 Bishop's Castle earthquake are not readily available, but the aforesaid sources taken together appear clearly to indicate that between 1% and 20% of properties in towns near the epicentre suffered damage of

European Macroseismic Scale The European macroseismic scale (EMS) is the basis for evaluation of seismic intensity in European countries and is also used in a number of countries outside Europe. Issued in 1998 as an update of the test version from 1992, the scale is referred ...

Grade 7 severity. The Welsh Borders suffer frequent earthquakes by British standards. Over the last century, there have been sizeable shocks near

Hereford Hereford () is a cathedral city, civil parish and the county town of Herefordshire, England. It lies on the River Wye, approximately east of the border with Wales, south-west of Worcester and north-west of Gloucester. With a population ...

in 1896 and 1924, near Shrewsbury in 1932, and near

Ludlow Ludlow () is a market town in Shropshire, England. The town is significant in the history of the Welsh Marches and in relation to Wales. It is located south of Shrewsbury and north of Hereford, on the A49 road which bypasses the town. The t ...

in 1926.

References

{{DEFAULTSORT:1990 Bishop's Castle Earthquake 1990 Bishops

Bish is a Japanese alternative idol girl group that was founded in 2015 by their manager Junnosuke Watanabe. The group was conceived as a successor to BiS, an idol group managed by Watanabe that disbanded in 2014. History Bish was initially ann ...

Bishops A bishop is an ordained clergy member who is entrusted with a position of authority and oversight in a religious institution. In Christianity, bishops are normally responsible for the governance of dioceses. The role or office of bishop is ca ...

20th century in Shropshire April 1990 events in the United Kingdom 1990 disestablishments in the United Kingdom

Location, date and time

Cause

Magnitude

Impact

See also

References