THE Greater Manchester area rocked again today as the number of earthquakes to shake the city during the last 24 hours rose to at least 15, the British Geological Survey said.

Latest information from the British Geological Survey website HERE

At just before 1.30pm today gasps were heard coming from shocked workers and shoppers in the city centre as a tremor with a preliminary figure of 2.5 on the Richter scale was recorded.

It follows yesterday's tremors which reached the Bolton and Horwich areas.

The shakes today were the latest in a series of tremors to shake Greater Manchester, leaving experts "excited" about analysing the "unusual'' findings.

The first earthquake alarmed people arriving for work yesterday at 8.45am and measured 3.2 on the Richter scale.

A bigger earthquake - 3.9 on the Richter scale - shook the city yesterday lunchtime and police reported up to 190 calls from concerned residents.

Julian Bukits, assistant seismologist at the British Geological Survey in Edinburgh, said further tremors were recorded throughout yesterday evening and at 4.39am a tremor measuring 2.9 on the Richter scale was recorded, followed by a number of smaller earthquakes being recorded up to 1pm today.

And at just before 1.30pm the city centre of Manchester rumbled again.

"It looks like this earthquake is slowly releasing its energy," said Mr Bukits, who added that the West Midlands earthquake last month was just one blast measuring 4.8 on the Richter scale.

He continued: "That makes the experiences in Manchester different. It's not one big bang. It makes it interesting, distinctive and unusual.

"It will be exciting looking at all the information we are collecting when we get time."

More than 1,200 people have e-mailed the British Geological Survey's website to share their experiences of the earthquakes.

Mr Bukits said the epicentre of the earthquakes stretches for 10 kilometres across the city centre of Manchester.

Alarmed workers reported office blocks shaking in Churchgate throughout yesterday morning.

And windows rattled in high-rise flats, department stores, college lecture rooms and terraced homes.

The first quake measured 3.2 on the Richter scale and stuck at 8.45am as thousands of commuters were heading to work.

It was followed by a second tremor measuring 2.3 on the scale at 9.04am.

At 12.42 the region was hit by a third earthquake measuring 3.9 on the Richter scale -- 11 times bigger than the first.

It was followed seconds later by a final quake measuring 3.4 on the scale.

A Bolton Council spokesman said: "We have now arranged for our engineers to check all our multi-storey buildings, including the town hall.

"We had no reports of any damage so this was purely a precautionary measure. The engineers will ensure there are no further risks."

The epicentre of the quakes, which were caused by movements in the earth's crust, was Beswick in Manchester.

The largest of the tremors had the same force as 1,000 tonnes of dynamite or a small nuclear weapon.

Greater Manchester Fire Service received 58 calls in the 15 minutes following yesterday afternoon's two tremors.

Firefighters dealt with falling signs and cracked chimneys. Many of the calls were from people alarmed by their shaking homes.

Gillian Barker, a secretary at the Bolton Institute, said: "I was just sitting at my computer when the desk and a chair nearby began to move.

"I felt like a very large lorry had gone past outside. It was very intense."

Emma Hatton, who works at the University of Manchester Institute of Science and Technology, said the floor and walls of her office were shaking.

The 27-year-old from Horwich said: "The windows rattled and it sounded violent. It was an unnerving moment. Everyone stopped working and looked at each other."

Birmingham experienced a quake measuring 4.8 on the Richter scale exactly one month ago.

Seismologists said yesterday's quakes were also quite big for the UK, but small compared to the earthquakes experienced in Japan and California.

David Galloway of the British Geological Survey said: "We received a lot of calls about yesterday's four earthquakes from all over Greater Manchester.

"We get about four or five quakes of that size every year, so it is unusual to get three in one day."

This is how the BGS website has recorded events:

SEISMIC ALERT: MANCHESTER 22 OCTOBER 2002 12:28 UTC MAGNITUDE 3.2 ML

BGS have received a number of calls from the general public and the media regarding a further felt earthquake in the Greater Manchester area

this afternoon at 13:28 BST. Felt reports have described "furniture shake" and "bed shook violently".

SEISMIC ALERT: MANCHESTER 22 OCTOBER 2002 03:39 UTC MAGNITUDE 2.9 ML

BGS have received a number of calls from the local authorities, the general public and the media regarding a further felt earthquake in the Greater

Manchester area this morning at 04:39 BST. Felt reports have described "the whole house shook" "we were woken from sleep", "the room shook

violently" and "we were alarmed".

The following preliminary information is available for this earthquake:

DATE : 22 October 2002

ORIGIN TIME : 03:39 37.6 s UTC

LAT/LONG : 53.47 North / 2.21 West

GRID REF : 385.5 kmE / 396.3 kmN

DEPTH : 5.0 km

MAGNITUDE : 2.9 ML

LOCALITY : Manchester, Greater Manchester

This morning's earthquake occurred in the same general vicinity as the four earthquakes that occurred yesterday with magnitudes ranging from

2.3 - 3.9 ML. A number of smaller events have also occurred since yesterday's magnitude 3.9 ML earthquake at 11:42 UTC with the largest having

a magnitude of 2.0 ML (22 October 2002 03:54 UTC).

SEISMIC ALERT: MANCHESTER 21 OCTOBER 2002 11:42 UTC MAGNITUDES 3.9 ML & 3.5 ML, RESPECTIVELY

BGS have received many more calls from the local authorities and the general public of two further earthquakes in the Greater Manchester area

today at 12:42 BST. The first event has a preliminary magnitude of 3.9 ML, followed by a magnitude 3.5 ML approximately 20 seconds later. Felt

reports have described "the whole house shook" and "pc monitors moved". It has been reported that some people evacuated buildings and many

were frightened by the experience.

The following preliminary information is available for the mainshock:

DATE : 21 October 2002

ORIGIN TIME : 11:42 34.9 s UTC

LAT/LONG : 53.48 North / 2.22 West

GRID REF : 385.4 kmE / 398.0 kmN

DEPTH : 5.0 km

MAGNITUDE : 3.9 ML

LOCALITY : Manchester, Greater Manchester

These earthquakes occurred in the same general vicinity as the two this morning at 07:45 UTC and 08:04 UTC, magnitudes 3.2 ML & 2.3 ML,

respectively (details below).

SEISMIC ALERT: MANCHESTER 21 OCTOBER 2002 07:45 UTC 3.2 ML

Today BGS have received felt reports from residents throughout Greater Manchester of a felt earthquake at 07:45 UTC. The felt reports

described "whole house shook", "I was alarmed", "furniture moved" and "windows and doors rattled". This event was followed by a magnitude 2.3

ML aftershock, which occurred some 19 minutes later.

The following preliminary information is available for the mainshock:

DATE : 21 October 2002

ORIGIN TIME : 07:45 15.8s UTC

LAT/LONG : 53.48 North / 2.19 West

GRID REF : 387.0 kmE / 397.6 kmN

DEPTH : 3.4 km

MAGNITUDE : 3.2 ML

LOCALITY : Manchester, Greater Manchester

Today's event locates some 14 km west of the magnitude 2.6 ML Manchester earthquake, which occurred on 5 December 1987, and was felt with

intensities of 4 EMS and also locates approximately 30 km ENE of the magnitude 4.5 ML Widnes event, which occurred on 3 November 1976.

Today's earthquake locates approximately 105 km north of the Dudley earthquake, which occurred on 22 September 2002, with a magnitude of

5.0 ML.