Publications of Alain Demoulin
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See detailPast landslides in the Verviers (E Belgium) area: climate- or earthquake-induced features?
Demoulin, Alain ULiege; Pissart, Albert ULiege

in Cahiers du Centre Européen de Géodynamique et de Séismologie (2001)

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See detailTectonic vs. shallow origin of geodetically inferred ground movements: an NE Ardenne (Belgium) case
Demoulin, Alain ULiege; Vliegen, Bernard; Charlier, Robert ULiege

in Earth and Planetary Science Letters (2000), 181(1-2), 217-228

In order to get a better insight into the temporal pattern of height change variations in a moderately seismic intraplate area, a 1 km long section has been weekly leveled from April, 21, 1997 to January ... [more ▼]

In order to get a better insight into the temporal pattern of height change variations in a moderately seismic intraplate area, a 1 km long section has been weekly leveled from April, 21, 1997 to January, 12, 1998 in NE Ardenne (Belgium). As this section is located very close to a small reservoir of 25 X 10(6) m(3), it also allowed the influence of lake level variations on the nearby ground motion to be studied. The measured height difference variations show a maximum amplitude of 3.45 mm, with weekly values not exceeding 1 mm. A two-dimensional (2D) finite element modeling confirms that waterload variations in the lake are the primary cause of movement of the section, inducing maximum ground subsidence of about 2 cm and seasonal tilting of 3-4 mu rads within a range of 2-3 km. We also show that a fault passively alters the spatial distribution of the waterload-dependent movements. The removal of this component from the observed ground motion leaves oscillating residual displacements characterized by an amplitude of 1-1.5 mm and a 'period' of about 2 months. We demonstrate that these displacements are independent of rainfall and probably of groundwater fluctuation too. Although most of the residual motions take place on the fault straddled by the leveling section, no credible mechanism can be found to ascribe these motions to a tectonic process. (C) 2000 Elsevier Science B,V. All rights reserved. [less ▲]

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See detailLes glissements de terrain du Pays de Herve (Battice-Manaihant, Belgique)
Demoulin, Alain ULiege; Pissart, Albert ULiege; Poty, Edouard ULiege et al

Report (2000)

Lors des levés de terrain réalisés en 1997-1998 dans le cadre de la révision de la carte Dalhem-Herve (révision de la carte géologique de la Wallonie), Barchy et Marion ont découvert des morphologies ... [more ▼]

Lors des levés de terrain réalisés en 1997-1998 dans le cadre de la révision de la carte Dalhem-Herve (révision de la carte géologique de la Wallonie), Barchy et Marion ont découvert des morphologies particulières, à l'aval de décrochements actifs, visibles à la surface du sol (notamment à Manaihant et Battice). Ces structures ont aussi été identifiées sur des photographies aériennes et leur statut de glissements de terrain a été confirmé par Pissart. Ces glissements de terrain sont particulièrement bien visibles sur le site WalOnMap du SPW (MNT 2013-2014 "Hillshade") [less ▲]

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See detailTesting the tectonic significance of some parameters of longitudinal river profiles: the case of the Ardenne (Belgium, NW Europe)
Demoulin, Alain ULiege

in Geomorphology (1998), 24

The longitudinal profiles of 24 rivers of 3rd to 5th order have been analyzed in order to recognize the regional tectonic differentiation pattern of the Ardenne, a Paleozoic massif of NW Europe. Data ... [more ▼]

The longitudinal profiles of 24 rivers of 3rd to 5th order have been analyzed in order to recognize the regional tectonic differentiation pattern of the Ardenne, a Paleozoic massif of NW Europe. Data collected exclusively from 1/25,000 topographic maps were used to define a set of parameters related to the geometry of the profile and proxies for river bedload and drainage area. Validation of the proxy defined for the bedloadrdischarge ratio demonstrates its potential use for inter-river comparison based on its value at the river mouth; it is however inadequate to estimate the ratio changes along a given stream course. This proxy has been computed to estimate the portion accounted for by hydrodynamic factors in the river bed profiling. Thus, outliers to the correlation function linking it to the river bed gradient have been considered as undergoing other influences, principally of lithologic or tectonic origin. Most indicative of the computed profile parameters are those related to the concavity of the profile. Four more or less regional longitudinal profile types are recognized which are partly determined by differential tectonic movement. The combined analysis of all the parameters confirms the current uplift of the NE Ardenne and points to a subsidence of the Namur area with respect to its SW and SE surroundings. Whether periglacial or tectonic in origin, the Upper Pleistocene lowering of a local base-level has also been identified in the Famenne. Another conclusion of this study is that in order to evidence tectonic influences and to avoid any misinterpretation in a region of complex geologic and geomorphic history and moderate tectonic activity, it is essential to consider a number of parameters and to consider their significance within the framework of detailed geologic setting and morphogenetic history. [less ▲]

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See detailNeotectonic implications of a lineament-coplanarity analysis in Southern Calabria, Italy
Cornet, Yves ULiege; Demoulin, Alain ULiege

in Geological Society Special Publication (1998), 146

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See detailL’Ardenne. Essai de géographie physique
Demoulin, Alain ULiege

Book published by Dépt de Géographie physique et Quaternaire, ULg (1995)

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See detailNeotectonic activity in and around the southwestern Rhenish shield (West Germany): indications of a levelling comparison
Demoulin, Alain ULiege; Pissart, Albert ULiege; Zippelt, K.

in Tectonophysics (1995), 249(3-4), 203-216

Precise levelling data are re-examined in the southwestern Rhenish shield and its foreland by comparing them analytically along levelling profiles. Instead of generalizing regional vertical movement ... [more ▼]

Precise levelling data are re-examined in the southwestern Rhenish shield and its foreland by comparing them analytically along levelling profiles. Instead of generalizing regional vertical movement trends, this method emphasizes the activity of individual structural elements, which can be located with a high accuracy. It is shown that present-day vertical motions concentrate on fractures which cut the massif into a number of tectonic blocks. These undergo more or less independent movements. Significant measured displacements range from 1 to 3.5 cm over an average 20-year period and correspond mostly to aseismic slip. High displacements are found near pre-existing faults, sometimes also zones of joint concentration which are favourably oriented with respect to the current regional stress field. In the Mosel area, SW-NE-trending faults are predominantly reactivated as reverse faults. The motion inferred for the Hunsrück border fault is also consistent with the compressive regime presently observed in that area, with σ1 oriented to the northwest. The direction of vertical motions along the western border fault of the upper Rhine graben changes from south to north in relation to the different azimuths of the central and northern segments of the graben, inducing a S-N-oriented transition from compressional to extensional shear. Within the graben itself, some N160°E-trending normal faults are identified, one of them having probably ruptured in a swarm of microearthquaks not long before the second survey was performed. The western Saar-Nahe trough is characterized by N-S-oriented fractures which cannot be related to mapped faults but show a close connection with photolineaments. © 1995. [less ▲]

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See detailL'apport de la géodésie à la néotectonique des massifs anciens
Demoulin, Alain ULiege; Pissart, Albert ULiege; Zippelt, K

in Würzburger Geographischen Arbeiten (1993), 87

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See detailLes régions néotectoniques de la Belgique définies par la comparaison de nivellements
Demoulin, Alain ULiege; Lenôtre, N; Moxhet, J. et al

in Annales de la Société Géologique de Belgique (1992), 115(1), 99-111

Une comparaison analytique des nivellements de précision de 1948 et 1980 en Belgique a été réalisée le long de profils figurant les variations d'altitude entre ces deux dates, ainsi que Fourniguet l'a ... [more ▼]

Une comparaison analytique des nivellements de précision de 1948 et 1980 en Belgique a été réalisée le long de profils figurant les variations d'altitude entre ces deux dates, ainsi que Fourniguet l'a réalisé dès 1987 pour le Nord de la France. Cette méthode qui permet un repérage précis des discontinuités entre zones de comportements tectoniques différents, a fourni un découpage de la Belgique en cinq régions. Parmi celles-ci, les Flandres d'une part, le Condroz et l'Ardenne centrale d'autre part sont stables. Une troisième région géodynamique correspond à l'est de la Belgique, affecté de fractures NO-SE dont l'activité est liée à celle du rift rhénan. La partie centrale du massif de Brabant semble pour sa part parcourue de cassures NE-SO dont le jeu détermine un affaissement en escaliers vers le SE. Enfin, le sud-ouest et le sud de la Belgique constituent la cinquième région, en surrection actuellement au sud d'une large flexure NO-SE. De plus, les discontinuités décelées sur les profils de nivellement coïncident en général remarquablement avec des failles connues. [less ▲]

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See detailThe Stavelot Massif from Cambrian to recent. A survey of the present state of knowledge
Bless, M. J. M.; Bouckaert, J.; Camelbeek, L. et al

in Annales de la Société Géologique de Belgique (1990)

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See detailResearch in the laboratory of Geomorphology and Geology of the Quaternary at the University of Liege
Pissart, Albert ULiege; Ek, Camille ULiege; Gewelt, M et al

in Bulletin de la Société Belge d'Études Géographiques (1988), 57

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See detailLes surfaces d'érosion crétacique et paléogènes du nord de l'Ardenne-Eifel
Demoulin, Alain ULiege

in Zeitschrift für Geomorphologie (1986), 30

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See detailNote sur le dépôt caillouteux de G'doumont (Malmedy)
Demoulin, Alain ULiege

in Bulletin de la Société Géographique de Liège (1982)

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See detailL'évolution géomorphologique du plateau des Hautes Fagnes et de son versant septentrional
Demoulin, Alain ULiege

in Bulletin de la Société Belge d'Études Géographiques (1980)

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