Seismicity
& energy
When the Richter Scale was
created in 1932, the smallest
tremors that could be recorded
and located at the time were
of magnitude 3. The geology
in the Bowland Basin means
that seismic events, regardless of
their cause, are unlikely to exceed
this magnitude.
Research led by Durham University, released in April 2013, found that almost all of the resultant
seismic activity from hydraulic fracturing was on a small scale that only geoscientists would be
able to detect.
Professor Richard Davies, from the Durham Energy Institute, said:
Most fracking-related events release a negligible
amount of energy roughly equivalent to or even less
than someone jumping off a ladder onto the floor.
Worldwide seismicity
Magnitude Description Earthquake effects Frequency of occurrence
Less than 2.0 Micro 2.0-2.9 Minor 3.0-3.9 Minor
4.0-4.9 Light Moderate 5.0-5.9 Strong 6.0-6.9 7.0-7.9 Major 8.0-8.9 Great 9.0-9.9 Devastating 10.0+ Massive Micro earthquake, not felt. Generally not felt, but recorded. Often felt, but rarely causes damage. Noticeable shaking of indoor items, rattling noises. Significant
damage unlikely.
Can cause major damage to poorly constructed buildings over small
regions. At most slight damage to
well-designed buildings.
Can be destructive in areas up to about 160 kilometres (99 mi) across
in populated areas.
Can cause serious damage over larger areas.
Can cause serious damage in areas several hundred kilometres across.
in areas several thousand
kilometres across.
Never recorded, widespread devastation across very large areas. Extremely rare
Continual
1,300,000 per year (est.)
130,000 per year (est.)
13,000 per year (est.)
1,319 per year
134 per year
15 per year
1 per year
1 per 10 years (est.)
(Unknown/may
not be possible)
Based on U.S. Geological Survey documents
The graph shows recent seismic events
in the UK by actual energy released
compared to an earthquake in
Lincolnshire in 2008, which was the
largest seismic event in the UK since
1984. The amount of energy released at
each level on the Richter Scale is
tremendously different.
3,990,643
4,000,000
3,500,000
3,000,000
2,500,000
2,000,000
1,500,000
Earthquake magnitude scales are
logarithmic. This means that the energy
released from a magnitude 2
earthquake is 32 times greater than a
magnitude 1 earthquake. As illustrated
in the graph opposite, it would take
th
almost 363,000 of the 27 May events
st
and over 22,000 of the 1 April events
to equal the energy from the
Lincolnshire earthquake in 2008.
1,000,000
500,000
355,665
11
1.5 MLŁ
BlackpoolŁ
May 27
178
2.3 MLŁ
BlackpoolŁ
April 1
2,000
3.0 MLŁ
Level
4.5 ML
WidnesŁ
1976
Energy released in Mega Joules –
Comparing seismicity in the UK
5.2 MLŁ
Lincolnshire
2008