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Active and recent deformation at the Southern Alps – Ligurian basin junction

  • C. Larroque (a1) (a2), N. Béthoux (a1), E. Calais (a1), F. Courboulex (a1), A. Deschamps (a1), J. Déverchère (a1), J.-F. Stéphan (a1), J.-F. Ritz (a3) and E. Gilli (a4)...


The Southern Alps – Ligurian basin junction is one of the most active seismic areas in Western Europe countries. The topographic and the structural setting of this region is complex because of (i) its position between the high topography of the Southern Alps and the deep, narrow Ligurian oceanic basin, and (ii) the large number of structures inherited from the Alpine orogeny. Historical seismicity reveals about twenty moderate-size earthquakes (up to M=6.0), mostly distributed along the Ligurian coast and the Vésubie valley. A recent geodetic experiment shows a significant strain rate during the last 50 years in the area between the Argentera massif and the Mediterranean coastline. Results of this experiment suggest a N-S shortening of about 2-4 mm/yr over the network, this shortening direction is consistent with the seismological (P-axes of earthquakes) and the microtectonic data. The Pennic front (E-NE of the Argentera massif) and the northern Ligurian margin are the most seismically active areas. In the Nice arc and in the Argentera massif, some seismic lineaments correspond to faults identified in the field (such as theTaggia-Saorge fault or the Monaco-Sospel fault). In the western part of the Alpes Maritimes, no seismic activity is recorded in the Castellane arc. In the field, geological evidence, such as offsets of recent alluvial sediments, recent fault breccia, speleothem deformations, radon anomalies and others indicates recent deformation along these faults. Nevertheless, to this date active fault scarps have not been identified: this probably results from a relatively high erosion rate versus deformation rate and from the lack of Quaternary markers. We also suspect the presence of two hidden active faults, one in the lower Var valley (Nice city area) and the other one at the base of the Argentera crustal thrust-sheet. Offshore, along the northern Ligurian margin, the seismic reflection data shows traces of Quaternary extensional deformation, but the accuracy of the data does not yet allow the construction of a structural map nor does it allow the determination of the continuity between the offshore and onshore structures. From these data set we propose a preliminary map of 11 active faults and we discuss the questions which remain unsolved in the perspective of seismic hazard evaluations.

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Augliera, P., Béthoux, N., Déverchère, J. & Eva, C., 1994. The Ligurian Sea: new seismotectonic evidence. Boll. Geofis. Teorica Appl., XXXVI (141144), 363380.
Azzaro, R., 1999. Earthquake surface faulting at the Mount Etna volcano (Sicily) and implications for active tectonics. J. of Geodynamics, 28, 193213.
Basili, R., Bosi, V., Galadini, F., Galli, P., Meghraoui, M., Messina, P., Moro, M. & Sposato, A., 1998. The Colfiorito earthquake sequence of september-october 1997: surface breaks and seismotectonic implications for the Central Apennines (Italy). J. of Earth. Eng., 2, 291302.
Baubron, J.C., 1987. Compte rendu détaillé, Argentera (Alpes Italiennes). BRGM, diffusion délégation Risques Majeurs, 3 pp.
Baroux, E., Béthoux, N. & Bellier, O., 2000. Analyses of the stress field in southeastern France from earthquake focal mechanisms. In press Geophys. J. Int.
Bigot-Cormier, F., Poupeau, G. & Sosson, M., 2000. Differential denudations of the Argentera external crystalline massif (SE France) reavaled by fission tracks thermochronology (zircons, apatites). C. R. Acad. Sci. Paris, 330, 363370.
Béthoux, N., Cattaneo, M., Delpech, P.Y., Eva, C., & Réhault, J.P., 1988. Mécanismes au foyer de séismes en mer Ligure et dans le Sud des Alpes occidentales: résultats et interprétations. C. R. Acad. Sci. Paris, 307, 7177.
Béthoux, N., Fréchet, J., Guyoton, F. Thouvenot, F., Cattaneo, M., Eva, C., Nicolas, M., & Granet, M., 1992. A closing Ligurian sea, Pure Appl. Geoph., 139, 179194.
Béthoux, N., Ouillon, G. & Nicolas, M., 1998. The instrumental seismicity of the western Alps: Spatio-temporal pattern. Geophys. J. Int., 135, 177194.
Borchielini, S., Campredon, R. & Bernat, M., 1991. Ground variation of Radon 222 for location of hidden structural features. Example of the South of France (Alpes Maritimes). Pageoph., 135, 625638.
Boschi, E., Ferrari, G., Gasperini, P., Guidoboni, E., Smriglio, G. & Valensise, G., 1995. Catalogo dei forti terremoti in Italia dal 461 a.C. al 1980. Istituto Nazionale di Geofisica-Storia Geofísica Ambiente, Bologna, 973 pp.
Boschi, F., Guidoboni, E., Ferrari, G., Valensise, G. & Gasperini, P., 1997. The catalogue of strong Italian Earthquakes on the web.
Bossolasco, M. & Eva, C., 1965. Il terremoto del 19 luglio 1963 nel mar Ligure. Geofis. e Meteor., 14, 618.
Bulard, P.F., Chamagne, B., Dardeau, G., Delteil, J., Gioan, P., Ivaldi, J.P., Laval, F., Perez, J.L. & Polvèche, J., 1975. Sur la genèse et les structures de Tare de Nice. Bull. Soc. Géol. de France, XVII.
Cabrera, J. & Sébrier, M., 1998. Surface rupture associated with a 5.3 mb earthquake: the 5 April 1986 Cuzco earthquake and kinematics of the Chincheros-Qoricocha faults of the High Andes, Peru. Bull. Seism. Soc. Am., 88, 242255.
Calais, E., Galisson, L., Stéphan, J.F., Delteil, J., Déverchère, J., Lar-roque, C., Mercier de Lépinay, B., Popoff, M. & Sosson, M., 2000. Crustal strain in the southern Alps, France, 1948–1998. Tectonophysics, 319, 117.
Camelbeeck, T., Martin, H., Vanneste, K., Meghraoui, M., Verbeeck, K. & Brondeel, M., 2000. Geomorphic evidence of active faulting in slow deformation area: the exemple of the Lower Rhine Embayment. Workshop «Evaluation of the potential for large earthquakes in region of present-day low seismic activity in Europe», Han sur Lesse, 13–17 March 2000, abstract volume, 3134.
Chaumillon, E., Deverchère, J., Rénault, J.P. & Gueguen, E., 1994. Réactivation tectonique et flexure de la marge continentale Ligure (Méditerranée Occidentale). C.R. Acad. Sc, Paris, 319, 675682.
Clauzon, G., Rubino, J.L. & Suc, J.P., 1996. Les rias pliocènes du Var et de Ligurie: comblement sédimentaire et évolution géodynamique. Field trip book of the Groupe Français d’Etude du Néogène/Groupe Français de Géomorphologie, 36p.
Combes, P., 1984. La tectonique récente de la Provence occidentale: microtectonique, caractéristiques dynamiques et cinématiques. Méthodologie de zonation tectonique en relation avec la sismicité. Thèse de doctorat, Univ. de Strasbourg, 182 pp.
Cosani, L., 1997. Neotectonique et heritage structural entre massif du Mercantour et marge ligure: le secteur de Saorge-Taggia. Géologie Alpine, 128134.
Courboulex, F, Deschamps, A., Cattaneo, M., Costi, F., Deverchère, J., Virieux, J., Augliera, P., Lanza, V. & Spallarossa, D., 1998. Source study and tectonic implications of the 1995 Ventimiglia (border of Italy and France) earthquakes (ML=4.7). Tectonophysics, 290, 245257.
Courboulex, F., Duval, A.M., Lomax, A., Deschamps, A. & Larroque, C., 2000. Les enseignements du petit séisme de Peille (Mw=3.4) du 1er novembre 1999 (Alpes Maritimes, France). Congrès Riviera 2000 «Tectonique active et géomorphologie» 18–22 octobre 2000, Villefranche sur Mer, abstract volume, 11.
DeMets, C., Gordon, R.G., Argus, D.F. & Stein, S., 1994. Effect of recent revisions to the geomagnetic reversal time scale on estimates of current plate motions. Geophys. Res. Letters, 21, 21912194.
Dubar, M., & Perez, J.L., 1989. Quaternary neotectonics bordering on the subalpine ‘Arc de Nice’. CR. Acad Sci., Paris, 308, 14851490.
Dubar, M., Gugliemi, Y. & Falgueres, C., 1992. Néotectonique et sédimentation côtière quaternaire en bordure de Tare subalpin de Nice (Alpes Maritimes, France). Quaternaire, 3, (34), 105110.
Dubar, M. & Gugliemi, Y., 1996. Morphogenèse et mouvements verticaux quaternaires en bordure de l’arc de Nice, essai de quantification. Rev. d’Anal. Spatiale Quant. App., 38, 2127.
Duval, A.M., 1996. Détermination de la réponse d’un site aux séismes à l’aide du bruit de fond: évaluation expérimentale. Thèse de doctorat de l’Univ. Paris VI, 265 pp.
Eva, C. & Rabinovich, A.B., 1997. The Febuary 23, 1887 tsunami recorded on the Ligurian coast, western Mediterranean. Geophys. Res. Lett., 24, 22112214.
Eva, C., Augliera, P., Burgisi, C., Eva, E., Solarino, S. & Spallarossa, D., 2000. New evidences on the seismotectonics of the Saorge-Taggia Line from analysis of the recent seismicity. Europ. Geophys. Soc. 25th general assembly, 2629 April, Nice.
Fauquette, S., Clauzon, C., Sue, J.P. & Zheng, Z., 1999. A new approach for palaeoaltitude estimates based on pollen records: example of the Mercantour Massif (southeastern France) at the earliest Pliocene. Earth Planet. Sci. Lett., 170, 3547.
Ferhat, G., Feigl, K., Ritz, J.F. & Souriau, A., 1998. Geodetic measurement of tectonic deformation in the southern Alps and Provence, France, 1887–1994. Earth Planet. Sci. Lett., 159, 3546.
Ferrari, G., 1991. The 1887 Ligurian earthquake: A detailed study from contemporary scientific observations. Tectonophysics, 193, 131139.
Gaffet, S., Larroque, C., Deschamps, A. & Tressols, K., 1998. Dense array experiment for observation of waveform perturbation induced by local structure diffraction. Soil Dynamics and Earthquake Engineering, 17, 475484.
Gèze, B. & Lanteaume, M., 1963. Carte géologique de Menton-Nice, Editions BRGM.
Ghafiri, A., 1995. Paléosismicité de failles actives en contexte de sismiche modérée: application à l’évaluation de l’aléa sismique dans le Sud-Est de la France. Thèse de doctorat, Univ. Paris XI, 373 pp.
Gidon, M., 1977. Notice de la carte géologique de Larche, 1/50 000. Ed. BRGM.
Gidon, M. & Pairis, J.L., 1992. Relations entre le charriage de la Nappe de Digne et la structure de son autochtone dans la vallée du Bès (Alpes de Haute-Provence, France). Eclogae Geol. Helv., 85/2, 327359.
Gilli, E., 1981. Néotectonique dans les massifs karstiques. D.E.A. Univ. Aix-Marseille, 78 pp.
Gilli, E., 1986. Néotectonique dans les massifs karstiques, un exemple dans les préalpes de Nice: la grotte des Deux Gourdes. Karstologia, 8, FFS-AFK-CNRS, 5052.
Gilli, E. & Delange, P., 1999. Recent slow and aseismic movement of an overthrust observed in the Abel sink hole (Saint-Vallier-de-Thiey, Alpes Maritimes, France). Geodynamica Acta, Colloque de Han sur Lesse 1998.
Grellet, B., Combes, P., Granier, T. & Philip, H., 1993. Sismotec-tonique de la France Métropolitaine dans son cadre géologique et géophysique. Mem. Soc. Géol. de France, 164, 76 pp.
Hoang-Trong, P. Haessler, H., Holl, J.M. & Legros, Y., 1987. L’essain sismique (oct. 83 – Jan. 84) de la moyenne vallée de la Roya (Alpes Maritimes): activité récente d’un ancien système de failles conjuguées? C.R. Acad. Sci. Paris, 304, 419424.
Irr, F., 1984. Paléoenvironnements et évolution géodynamique néogènes et quaternaires de la bordure nord du Bassin Méditerranéen Occidental, un système de pente de la paléo-marge provençale. Thèse Université de Nice, 464 pp.
Klaucke, I., Savoye, B. & Cochonat, P., 2000. Patterns and processes of sediment dispersal on the continental slope off Nice, SE France. Marine Geol., 162, 405422.
Labaume, P., Ritz, J.F. & Philip, H., 1989. Recent normal faults in the southwestern Alps: their relationships with the compression tectonics. C.R.Acad. Sci. Paris 308, série II, 15531560.
Lambert, J. & Levret, A., 1996. Mille ans de séismes en France. Ouest Editions Presses Académiques, Nantes, 120 pp.
Larroque, C., Gaffet, S., Cornou, C., Schissele, E., Bertrand, E., Béthoux, N., Bouchon, M., Corrazzi, M., Courboulex, F., Deschamps, A., Duval, A.M., Marón, C., Glot, J.R, Janod, F., Guiguet, R., Vidal, S. &Virieux, J., 1999. Une expérience multi-antennes à Annot pour l’analyse des effets de site en sismologie. C. R. Acad. Sci. Paris, 329, 167174.
Larroque, C., Béthoux, N., Calais, E., Courboulex, F., Deschamps, A., Deverchère, J., Stéphan, J.F., Ritz, J.F. & Gilli, E., 2000. Joint Multidisciplinary studies of active faults and seismic hazard at the junction between southern French Alps and Ligurian basin. Abstract volume Paleosis, Han sur Lesse (Belgium), 1317 march 2000, 8992.
Laurent, O., 1998. Modalités de la structuration d’un prisme de front de chaîne: P example de l’arc de Castellane (chaînes subalpine Méridionales, France). PhD Thesis, Univ. Nice-Sophia Antipolis, 280 pp.
Laurenti, A., 1998. Les tremblements de terre des Alpes Maritimes. Serre, Editeur, Nice, 175 pp.
Lemoine, M., Dardeau, G., Delpech, P., Dumont, T., De Graciansky, C., Graham, R., Jolivet, L., Robert, D. & Tricart, P., 1989. Extension synrift et failles transformantes jurassiques dans les Alpes Occidentales. C.R. Acad. Sci. Paris, 309, 17111716.
Levret, A., Cushing, M. & Peyridieu, G., 1996. Etude des caractéristiques des séismes historiques en France. IPSN, Paris, 399 pp.
Masana, E., Villamarin, J.A., Sanchez Cabañero, J., Plaza J. & Santanach, P., 2000. Seismological behaviour of a fault with no historical seismicity: El Camp fault (northeastern Iberian peninsula). Workshop «Evaluation of the potential for large earthquakes in region of present-day low seismic activity in Europe», Han sur Lesse, 13–17 March 2000, abstract volume, 101104.
Madeddu, B., Béthoux, N. & Stephan, J.F., 1996. Déformations et champs de contraintes récents à actuel dans les Alpes sud-occidentales: approche sismotectonique. Bull. Soc. Géol. de France, 167, 797810.
McKenzie, D., 1969. The relation between fault plane solutions for earthquakes and the directions of the principal stresses. Bull. Seism. Soc. Am., 59, 591601.
Meghraoui, M., Bosi, V., & Camelbeek, T., 1999. Fault fragment control in the 1997 Umbria-Marche, central Italy, earthquake sequence. Geophys. Res. Lett., 26(8),10691072.
Nicolas, M., Béthoux, N. & Maddedu, B., 1998. Instrumental seismicity of the Western Alps. Pure Appl. Geophys., 152, 707731.
Okada, Y., 1993. Surface deformation to shear and tensile faults in a half space. Bull. Seism. Soc. Am. 75, 148142.
Perez, J.L., 1975. La zone limite entre l’arc de Nice et l’arc de la Roya (Alpes Maritimes). Bull. Soc. Géol. de France, 7, 930938.
Rebaï, S., 1988. Le champ de contrainte actuel en Europe et dans les régions méditerranéennes. Etude du décrochement senestre plio-quaternaire de Laghet-Peille. D.E.A., Univ. de Montpellier, 36 pp.
Rebaï, S., Philip, H. & Taboada, A., 1992. Modern tectonic stress field in the Mediterranean region: evidence for variation in stress direction at different scales. Geophys. J. Int., 110, 106140.
Ritz, J.F., 1991. Evolution du champ de contraintes dans les Alpes du Sud depuis la fin de l’Oligocene. Thèse de doctorat, Univ. de Montpellier, 187 pp.
Ritz, J.F., 1992. Tectonique récente et sismotectonique des Alpes du Sud, analyse en termes de contraintes. Quaternaire, 3, 111124.
Saunders, I. & Young, A., 1983. Rate of surface processes on slopes, slope retreat and denudation. Earth Surf. Proc. and landforms, 8, 473501.
Sauret, B. & Terrier, M., 1987. Compte rendu de mission Argentera. BRGM, note BS/GR 87, 175.
Schroetter, J.M., 1998. L’enregistrement sédimentale de la déformation mio-plio-quaternaire sur la bordure ouest de Fare de Nice: analyse sedimento-morpho-structurale. Géologie Alpine, 74, 146149.
Siddans, A., Henry, P., Kligfield, B., Lowrie, W., Hirt, A. & Percevault, M., 1984. Finite strain patterns and their significance in permian rocks of the Alpes Maritimes (France). J. Struc.Geol., 6, 339368.
Sue, C., Thouvenot, F., Fréchet, J. &Tricart, P., 1999. Widespread extension in the core of the Western Alps revealed by earthquake analysis. J. Geophys. Res., 104, 25611-25622.
Vogt, J., 1981. Carte sismotectonique de la France au 1/1 000 000. CEA/EDF/BRGM/ Ministère de l’Industrie, Mém. BRGM, 111.
Wells, D.L. & Coppersmith, K.J., 1994. New empirical relationships among magnitude, rupture length, rupture width, rupture area and surface displacement. Bull. Seism. Soc. Am., 84, 9741002.
Westphal, M., Orsini, J. & Vellutini, P., 1976. Le microcontinent corso-sarde, sa position initiale, données paléomagnétiques et raccords géologiques. Tectonophysics, 30, 4157.
Working Group CPTI, 1999. Catalogo paramétrico dei Terremoti Italiani. ING, GNDT, SGA, SSN, Bologna, 92pp.


Active and recent deformation at the Southern Alps – Ligurian basin junction

  • C. Larroque (a1) (a2), N. Béthoux (a1), E. Calais (a1), F. Courboulex (a1), A. Deschamps (a1), J. Déverchère (a1), J.-F. Stéphan (a1), J.-F. Ritz (a3) and E. Gilli (a4)...


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