RATE AND PROCESSES OF RIVER NETWORK REARRANGEMENT DURING INCIPIENT FAULTING: THE CASE OF THE CAHABON RIVER, GUATEMALA
| العنوان: | RATE AND PROCESSES OF RIVER NETWORK REARRANGEMENT DURING INCIPIENT FAULTING: THE CASE OF THE CAHABON RIVER, GUATEMALA |
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| المؤلفون: | Barbara Suski, Klaus Holliger, Jane K. Willenbring, Gilles Brocard, B. Cosenza-Muralles, Sergio Morán-Ical, Pierre Rochette, P. Audrat, Christian Teyssier, Christine Authemayou, François Demory, Torsten Vennemann |
| المساهمون: | Institute of Geology and Paleontology, Université de Lausanne (UNIL), Department of Earth and Environmental Sciences [Philadelphia], University of Pennsylvania [Philadelphia], Institute of physics, Université de Nice, Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Domaines Océaniques (LDO), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Fac Engn, Dept Phys, Université de San Carlos, Centro Universitario del Noreste, Universitad de San Carlos, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut de Minéralogie et Géochimie [Lausanne], Department of Geology and Geophysics (DGG), University of Minnesota [Twin Cities], University of Minnesota System-University of Minnesota System, Université de Lausanne = University of Lausanne (UNIL), University of Pennsylvania, Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Minnesota [Twin Cities] (UMN), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA) |
| المصدر: | American journal of science American journal of science, American Journal of Science, 2012, 312 (5), pp.449-507. ⟨10.2475/05.2012.01⟩ American journal of science, 2012, 312 (5), pp.449-507. ⟨10.2475/05.2012.01⟩ |
| بيانات النشر: | HAL CCSD, 2012. |
| سنة النشر: | 2012 |
| مصطلحات موضوعية: | 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, Aquifer, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Fault (geology), tomography, 010502 geochemistry & geophysics, 01 natural sciences, Headward erosion, Drainage system (geomorphology), knickpoint propagation, Groundwater sapping, groundwater sapping, Geomorphology, 0105 earth and related environmental sciences, Canyon, geography, geography.geographical_feature_category, drainage reversal, Bedrock, Drainage reorganization, 15. Life on land, 6. Clean water, river capture, Tectonics, General Earth and Planetary Sciences, paleovalley, Geology, Al-26-Be-10 burial dating, tectonic defeat, electrical resistivity |
| الوصف: | International audience; Deeply incised river networks are generally regarded as robust features that are not easily modified by erosion or tectonics. Although the reorganization of deeply incised drainage systems has been documented, the corresponding importance with regard to the overall landscape evolution of mountain ranges and the factors that permit such reorganizations are poorly understood. To address this problem, we have explored the rapid drainage reorganization that affected the Cahabon River in Guatemala during the Quaternary. Sediment-provenance analysis, field mapping, and electrical resistivity tomography (ERT) imaging are used to reconstruct the geometry of the valley before the river was captured. Dating of the abandoned valley sediments by the Be-10-Al-26 burial method and geomagnetic polarity analysis allow us to determine the age of the capture events and then to quantify several processes, such as the rate of tectonic deformation of the paleovalley, the rate of propagation of post-capture drainage reversal, and the rate at which canyons that formed at the capture sites have propagated along the paleovalley. Transtensional faulting started 1 to 3 million years ago, produced ground tilting and ground faulting along the Cahabon River, and thus generated differential uplift rate of 0.3 +/- 0.1 up to 0.7 +/- 0.4 mm . y(-1) along the river's course. The river responded to faulting by incising the areas of relative uplift and depositing a few tens of meters of sediment above the areas of relative subsidence. Then, the river experienced two captures and one avulsion between 700 ky and 100 ky. The captures breached high-standing ridges that separate the Cahabon River from its captors. Captures occurred at specific points where ridges are made permeable by fault damage zones and/or soluble rocks. Groundwater flow from the Cahabon River down to its captors likely increased the erosive power of the captors thus promoting focused erosion of the ridges. Valley-fill formation and capture occurred in close temporal succession, suggesting a genetic link between the two. We suggest that the aquifers accumulated within the valley-fills, increased the head along the subterraneous system connecting the Cahabon River to its captors, and promoted their development. Upon capture, the breached valley experienced widespread drainage reversal toward the capture sites. We attribute the generalized reversal to combined effects of groundwater sapping in the valley-fill, axial drainage obstruction by lateral fans, and tectonic tilting. Drainage reversal increased the size of the captured areas by a factor of 4 to 6. At the capture sites, 500 m deep canyons have been incised into the bedrock and are propagating upstream at a rate of 3 to 11 mm . y(-1) deepening at a rate of 0.7 to 1 5 mm . y(-1). At this rate, 1 to 2 million years will be necessary for headward erosion to completely erase the topographic expression of the paleovalley. It is concluded that the rapid reorganization of this drainage system was made possible by the way the river adjusted to the new tectonic strain field, which involved transient sedimentation along the river's course. If the river had escaped its early reorganization and had been given the time necessary to reach a new dynamic equilibrium, then the transient conditions that promoted capture would have vanished and its vulnerability to capture would have been strongly reduced |
| اللغة: | English |
| تدمد: | 0002-9599 |
| DOI: | 10.2475/05.2012.01⟩ |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::791084f4108960a1dd2f6b9d18d04aee https://hal-insu.archives-ouvertes.fr/insu-00769852 |
| رقم الانضمام: | edsair.doi.dedup.....791084f4108960a1dd2f6b9d18d04aee |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 00029599 |
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| DOI: | 10.2475/05.2012.01⟩ |