Encyclopedia of geology, five volume set, volume 1 5 (encyclopedia of geology series) ( PDFDrive ) 2861
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324 TECTONICS/Earthquakes
compensated by a Mansion House Fund that paid out
£9000 (equivalent to £500 000 today). The Roermond earthquake in the Netherlands in 1998 (magnitude 5.8) caused £30–40 million of damage, despite
the single fatality. It is predicted that a magnitude 5.7
earthquake focused at a depth of 5 km directly under
Manchester would cause havoc. The increasing size
of conurbations and cities increases their vulnerability: the Colchester area would suffer much more
nowadays from a comparable earthquake to the
1884 event, because the population and industry are
now much denser than at that time.
Earthquakes can occur in areas that are not considered to be at risk. The Spitak earthquake in Armenia
in 1988 is such a case. The region was not considered to
be at high risk, and a nuclear power station was
planned for the Spitak area. This earthquake caused
the whole process of earthquake risk assessment in the
Soviet Union to be revised.
The New Madrid, Missouri, earthquakes of 1811–
1812 are even more surprising. There is a reliable
historical record of three earthquakes spaced over
two months with magnitudes 8.2, 8.1, and 8.3. They
rang the bells of Boston and rattled Quebec and
provide a remarkable example of major interplate
seismicity.
Figure 8 A railway track in the western USA twisted and
shortened by lateral motion during an earthquake.
Secondary effects The secondary effects of earthquakes can be as destructive and lethal as the primary
effects, or more so.
Figure 9 High rise buildings in Kobe after the 1995 earthquake, showing the sixth floor pancaked by vertical motion. Reproduced
from Esper P and Tachibana E (1998) The Kobe earthquake. In: Maund JG and Eddleston M (eds.) Geohazards in Engineering Geology, pp.
105 116. Engineering Geology Special Publication 15. London: Geological Society.
