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supply suddenly stopped. Reported damage included the collapse or partial collapse of
chimneys, broken windows, cracked ceilings and walls (source
: La Nouvelle Gazette
,
29 March 1967).
From the official inquiry of the Royal Observatory of Belgium, the most affected locali-
ties were Carnieres (20% of damage equal to or greater than moderate), Trazegnies (10%),
Morlanwez-Mariemont, Pieton, and Chapelle-lez-Herlaimont (7%) (
Figure 8.3
e
). Hence,
this type of earthquake causes moderate and extensive damage at a local scale.
The reports and eyewitness accounts from the newspapers about this earthquake can be
found via the link:
http://seismologie.be/cup2014.html
.
8.5.4 The 11 June 1938 Nukerke earthquake
On 11 June 1938 at 11 h 57 m (local time) an earthquake strongly shook western and central
Belgium, and northern France. It was also felt in the Netherlands, southeastern England, the
extreme west of Germany and the Grand Duchy of Luxemburg. The epicentre was located
more or less 50 km to the west of Brussels (
Figure 8.1
)
. With a magnitude M
5.0 and
large area (
Figure 8.3
d
). The investigation performed by Somville (
1939
)
at the time of the
earthquake describes the main effects produced by it. The main damage to buildings was
numerous falling chimneys; roughly 17,500 chimneys were damaged in Belgium alone,
which caused serious destruction of roofs and verandas. Many walls were cracked; some
of them collapsed. Inside houses, ceilings were cracked, some fell down; windows were
broken; numerous objects such as chimneypieces, large mirrors attached to walls, frames
or plates were dislodged and broken when falling to the ground. Large pieces of furniture
or beds were displaced.
In many localities, people inside buildings were frightened and ran outdoors, thinking
that their houses were near to collapse. In the fields, farmers felt the soil oscillating under
their feet and found it difficult to stand. Three people died and several dozen were injured.
Based on the inquiry done by the Royal Observatory of Belgium, the quantity of moderate
to extensive damage in all the localities of western Belgium is shown in
Figure 8.3
d
. The
most affected localities were Rekkem (48% of the houses), Kerksen (44%), Kortrijk (40%),
Bousval (37.5%), Outrijve (32%), and Court-Saint-Etienne (32%). The damage caused
to houses is unequally distributed on the two sides of an axis elongated in a more or less
northwest-southeast alignment with a length of 150 km centred on the earthquake epicentre.
To the south of this axis, moderate damage was observed in Belgium and southwards to the
French border. Unfortunately, there is no quantitative information from France to extend
the observations into northern France. The most significant damage occurred more or
less along the axis, sometimes at distances as large as 70 km (localities of Bousval and
Court-Saint-Etienne). To the north of the axis, damage appeared along an axis oriented
northeast-southwest, which corresponds to river valleys that incise the Meso-Cenozoic
sediments of the Brabant Massif. This damage distribution suggests that it is linked to the
thickness of the soft sediment cover and corresponds to the region where the soft sediment
=
