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Figure 2: Rocher de Freyr – protected rock outcrop (Dinantian
limestones).
Figure 3: Underground quarry (building stone = Maastricht limestone)
: site protected for cultural reasons (Caestert quarry, Kanne):
medieval graffiti on the wall (photograph: Bert Beckers).
Geoheritage potential in Belgium
The geology of Belgium forms the stage
where a large part of Earth’s history has
been elucidated: indeed, geologists make
worldwide use of chronostratigraphic
stage names coined in Belgium (Rupelian,
Ypresian, Visean, Tournaisian, Famennian,
Frasnian) or derived from border towns
where part of the type section is located in
Belgium (Maastrichtian, Givetian) (Fig.1).
As the legacy of pioneering 19 th century
geologists such as André Dumont and
Jules Gosselet, these stage names belong
as much to the global cultural heritage as
they refer to the local rock outcrops and
quarry sites in the historical name-giving
areas. If Belgian geologists had been more
attentive, this list could have been longer
and include, e.g. Landenian or Couvinian
(Dejonghe, 2006). It is primarily the responsibility
of present and future generations of
academic geoscientists to preserve the value
of these names and of regional geoscientists
to maintain the link between the historical
type areas and the preserved geoheritage.
The classical Meuse profile between Namur
and Givet, displaying different facies for
the Palaeozoic international
stage names, is hailed as one
of world’s finest showcases of
a geological succession in an
orogenic belt (Fig. 2).
Besides the sites and sections
linked to the chronostratigraphic
stages, Belgium
possesses emblematic
natural heritage sites with a
long history of human curiosity
about their geological
character. These sites where
underground expeditions
took place, before geology as
a science or the stratigraphical
time scale were established,
were the precursors to geotourism.
Examples are; the
natural caves of Han-sur-
Lesse, a model for a meander
cut by an underground river,
or the underground labyrinth
of Montagne St Pierre created
by room and pillar mining of
the Maastricht stone, where
the Mosasaurus hoffmanni
was discovered in 1770 and
subsequently deposited in
the Muséum in Paris as a
war trophy. Han-sur-Lesse
is a popular showcave but
has retained its importance
for geological research. The
underground quarries of Montagne St
Pierre have been destroyed by open cast
quarrying but efforts are being made to
protect the remaining underground quarries
(Fig. 3).
The recent morphological evolution
- epeirogenic uplift with river incision
- has exposed many more rock outcrops
or allowed their exploitation, showing
more than 500 million years
of geological history in a
restricted territory (Dejonghe
& Jumeau, 2007). This has
resulted in a legacy of rock
sections, type sections and
quarry sites of high regional
stratigraphical and educational
value (Fig. 4), many
if not most of which are
threatened by oblivion and
only occasionally the subject
of conservation. Fossil and
mineral occurrences sometimes
produce new minerals
(e.g. minerals first described
from Belgium, Hatert et al.,
2002; Van Der Meersche et al.,
2010) or exceptional fossil finds unmatched
elsewhere in the world (e.g. the Neogene
whales of Antwerp, or the Cran aux Iguanodons
in Bernissart, now the showcase of the
Natural History Museum in Brussels). The
industrial basin along the Meuse - Sambre
- Haine rivers was the start of the industrial
revolution on the European mainland,
fuelled by coal but with a rich and diversified
tradition of mineral extraction and
manufacturing (Goemaere et al., 2010).
Nowadays, its geoheritage is concealed
whereas the industrial heritage is acquiring
UNESCO World Heritage status (n° 1344).
Despite greening of the landscape, back
filling and the obligation to flatten slopes
of closed extraction sites, a number of
geosites still exist in some regions, while
in other regions former outcrops need to
be exhumed to display any contact with the
geological substrate. An inventory and classification
of these geosites including their
values and threats needs to be updated.
With respect to the industrial and mining
heritage, many initiatives for conservation
and development are already operational (cf
Dejonghe et al., 2009). Also, nature reserves,
natural parks and regional landscapes often
possess sites of geoscientific interest. The
insight that their preservation contributes to
ecosystem diversification is gaining ground
(Fig. 5). Indeed, new threats arise from the
vigorous restoration of more natural ecosystems.
Vulnerable landforms, resulting
from past and abandoned forms of land
use may be sacrificed, e.g. the blow-outs
uniquely preserved in the Bocholt plain (NE
Limburg) have been levelled to create new
nature areas.
A special category of urban geology,
historic monuments, whose raw material
source may have been lost in time, forms
Figure 4: The Beauchateau quarry: type section for Upper Frasnian
red mud mounds with a high educational value. Site also cherished
for outdoor activities and rock climbing (photograph: Pierres et
Marbres de Wallonie).
European Geologist 34 | November 2012
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