Effects of tectonics and lithology on long profiles of 16 rivers of the southern Central Massif border between the Aude and the Orb (France)

Abstract The analysis of longitudinal profiles of river channels and terraces in the southern Central Massif border, between the Aude and the Orb, allows the detection of anomalies caused by lithology and/or tectonic distortions. The rivers which have abnormally high slope and non-lithological knickzones indicate the main uplifted zones: the Montagne Noire and the Saint-Chinian ridge. A geomorphological and sedimentological analysis of detrital deposits was carried out as a basis for correlating the different formations, reconstructing the palaeodrainage and finding the main uplift and fluvial incision stages. During the Miocene, uplift remains limited as it is shown by the correlative fine deposits in the Languedocian piedmont. The Messinian incision (5.7–5.3 Ma) does not cross the Saint-Chinian ridge. On the other hand, fluvial incision becomes widespread in the Montagne Noire during the Upper Pliocene (3.4–2 Ma) when coarse deposits overlie either the Pliocene clay in the Orb palaeovalley or the Messinian conglomerates at the Cesse outlet. An Upper Pliocene uplift of the Montagne Noire and of the Saint-Chinian ridge is the cause of this incision and also of the diversion of the Cesse towards the Aude. Where the uplift rate was higher than incision rate, knickzones have developed like in the Avant-Monts south-side. The knickzones of lithological origin maintain a strong vertical stability during all the river incision stages. On the other hand, those of tectonic origin or base level lowering record upstream migration and their rate of retreat is controlled by the river discharge. As incision occurs only during the cold/temperate transition periods during the Quaternary, upward erosion slowly migrates (15 km since the Upper Pliocene, on the Orb) and so does not reach the riverheads.

[1]  O. Merle,et al.  The formation of the West European Rift; a new model as exemplified by the Massif Central area , 2001 .

[2]  K. Whipple.  BEDROCK RIVERS AND THE GEOMORPHOLOGY OF ACTIVE OROGENS , 2004 .

[3]  Stanley A. Schumm,et al.  Active Tectonics and Alluvial Rivers , 2002 .

[4]  J. Crochet.  CONTRIBUTIONS A L'ÉTUDE DES MICROMAMMIFÈRES DU GISEMENT MIOCÈNE SUPÉRIEUR DE MONTREDON (HÉRAULT) , 1982 .

[5]  J. Roering,et al.  Systematic variation of bedrock channel gradients in the central Oregon Coast Range: implications for rock uplift and shallow landsliding , 2004 .

[6]  A. Demoulin.  Testing the tectonic significance of some parameters of longitudinal river profiles: the case of the Ardenne (Belgium, NW Europe) , 1998 .

[7]  F. Pazzaglia,et al.  Knickzone propagation in the Black Hills and northern High Plains: A different perspective on the late Cenozoic exhumation of the Laramide Rocky Mountains , 2001 .

[8]  B. Gensous,et al.  L'analyse des dépôts postglaciaires et son application à l’étude des séquences de dépôt du Quaternaire terminal sur la plate-forme au large du Rhône (golfe du Lion) , 2003 .

[9]  J. Spotila,et al.  The form and function of headwater streams based on field and modeling investigations in the southern Appalachian Mountains , 2005 .

[10]  J. T. Hack,et al.  Stream-profile analysis and stream-gradient index , 1973 .

[11]  David J. Williams,et al.  Exponential longitudinal profiles of streams , 1997 .

[12]  Jean‑philippe Degeai.  Mesure de l'érosion post-éruptive autour des cratères de maars en inversion de relief dans le Massif central français / Post-eruptive erosion measurement around the inverted maar craters in the French Massif Central , 2004 .

[13]  Jean‑philippe Degeai.  Mesure de l'érosion post-éruptive autour des cratères de maars en inversion de relief dans le Massif central français , 2004 .

[14]  G. Tucker,et al.  Channel response to tectonic forcing: field analysis of stream morphology and hydrology in the Mendocino triple junction region, northern California , 2003 .

[15]  I. Fuller,et al.  Correlation of fluvial sequences in the Mediterranean basin over the last 200 ka and their relationship to climate change , 2002 .

[16]  B. Funnell.  Global sea-level and the (pen-)insularity of late Cenozoic Britain , 1995, Geological Society, London, Special Publications.

[17]  W. Ryan,et al.  Plio–Quaternary prograding clinoform wedges of the western Gulf of Lion continental margin (NW Mediterranean) after the Messinian Salinity Crisis , 2003 .

[18]  F. Lucazeau,et al.  Polyphased uplift and erosion of the Cévennes (southern France). An example of slow morphogenesis , 2002 .

[19]  B. Laignel,et al.  Les formations quaternaires de la France du Nord-Ouest : Limites et corrélations [The quaternary formations of North-West France : Boundaries and correlations] , 1998 .

[20]  G. Tucker,et al.  Landscape response to tectonic forcing: Digital elevation model analysis of stream profiles in the Mendocino triple junction region, northern California , 2000 .

[21]  K. Whipple,et al.  Quantifying differential rock-uplift rates via stream profile analysis , 2001 .

[22]  Michel Séranne,et al.  Surrection et érosion polyphasées de la bordure cévenole. Un exemple de morphogenèse lente , 2002 .

[23]  G. Tucker.  Drainage basin sensitivity to tectonic and climatic forcing: implications of a stochastic model for the role of entrainment and erosion thresholds , 2004 .

[24]  Irantzu Lexartza Artza,et al.  Knickpoint recession rate and catchment area: the case of uplifted rivers in Eastern Scotland , 2005 .

[25]  R. C. Preece.  Island Britain: A Quaternary Perspective , 1995 .

[26]  H. Piégay.  B. L. Rhoads and C. E. Thorn (Eds.) - The Scientific Nature of Geomorphology , 1998 .

[27]  G. Clauzon.  Limites de séquences et évolution géodynamique/Sequence boundaries and geodynamic evolution , 1996 .

[28]  J. T. Hack.  Studies of longitudinal stream profiles in Virginia and Maryland , 1957 .

[29]  Oliver A. Chadwick,et al.  An incision wave in the geologic record, Alpujarran Corridor, southern Spain (Almerı́a) , 2004 .

[30]  J. Michaux,et al.  Évolution géodynamique messino-pliocène en Languedoc central: le paléo-réseau hydrographique de l'Orb et de l'Hérault (sud de la France) , 1998 .

[31]  P. Davy,et al.  Did the Ebro basin connect to the Mediterranean before the Messinian salinity crisis , 2006 .

[32]  Rudy Slingerland,et al.  Stream Profile Adjustment to Crustal Warping: Nonlinear Results from a Simple Model , 1990, The Journal of Geology.

[33]  J. Schoorl,et al.  Late Cenozoic landscape development and its tectonic implications for the Guadalhorce valley near Álora (Southern Spain) , 2003 .

[34]  A. N. Strahler.  Hypsometric (area-altitude) analysis of erosional topography. , 1952 .

[35]  M. Rabineau,et al.  Paleo sea levels reconsidered from direct observation of paleoshoreline position during glacial maxima (for the last 500,000 yr) , 2006 .

[36]  D. Wilson,et al.  Chronology, causes and progression of the Messinian salinity crisis , 1999, Nature.

[37]  N. Pinter,et al.  Active Tectonics: Earthquakes, Uplift, and Landscape , 1995 .

[38]  Peizhen Zhang,et al.  Increased sedimentation rates and grain sizes 2–4 Myr ago due to the influence of climate change on erosion rates , 2001, Nature.

[39]  D. Dumitriu,et al.  Geomorphological evolution of longitudinal river profiles in the Carpathians , 2003 .

[40]  P. Bishop,et al.  Differentiating the Roles of Lithology and Uplift in the Steepening of Bedrock River Long Profiles: An Example from Southeastern Australia , 1995, The Journal of Geology.

[41]  A. Morton.  Geochemical studies of detrital heavy minerals and their application to provenance research , 1991, Geological Society, London, Special Publications.

[42]  Gilbert Saporta,et al.  Probabilités, Analyse des données et statistique , 1991 .

[43]  O. Merle,et al.  The evolution of the Massif Central Rift; spatio-temporal distribution of the volcanism , 2001 .

[44]  Jean‑Michel Carozza,et al.  L'escarpement de faille de la Têt est-il le résultat de la tectonique active Plio-Pléistocène ou d'une exhumation Pléistocène ? , 2004 .

[45]  W. Ryan,et al.  Late Miocene Desiccation of the Mediterranean , 1973, Nature.

[46]  C. Pomerol,et al.  Les minéraux en grains : méthodes d'études et détermination , 1970 .

[47]  M. Summerfield.  Geomophology and Global Tectonics , 2000 .

[48]  Andrew C. Morton,et al.  Processes controlling the composition of heavy mineral assemblages in sandstones , 1999 .

[49]  K. Whipple.  FLUVIAL LANDSCAPE RESPONSE TIME: HOW PLAUSIBLE IS STEADY-STATE DENUDATION? , 2001 .

[50]  G. Clauzon.  Limites de séquences et évolution géodynamique , 1996 .

[51]  D. Kalderon,et al.  Hedgehog acts as a somatic stem cell factor in the Drosophila ovary , 2001, Nature.

[52]  J. Gargani.  Modelling of the erosion in the Rhone valley during the Messinian crisis (France) , 2004 .

[53]  M. Tesson,et al.  Analysis of the postglacial deposits of the Rhône shelf (golfe du Lion). Implementation to the study of the late Quaternary depositional sequences , 2003 .

[54]  H. Ohmori.  Change in the Mathematical Function Type Describing the Longitudinal Profile of a River through an Evolutionary Process , 1991, The Journal of Geology.