{"id":674,"date":"2013-09-11T20:12:09","date_gmt":"2013-09-11T18:12:09","guid":{"rendered":"http:\/\/wp.unil.ch\/risk\/?p=674"},"modified":"2013-09-26T13:49:17","modified_gmt":"2013-09-26T11:49:17","slug":"valentin-metraux-quantification-de-lerosion-et-de-la-dynamique-sedimentaire-dans-un-bassin-versant-torrentiel-a-laide-de-la-teledetection-application-au-bassin-versant-du-merdenson","status":"publish","type":"post","link":"https:\/\/wp.unil.ch\/risk\/valentin-metraux-quantification-de-lerosion-et-de-la-dynamique-sedimentaire-dans-un-bassin-versant-torrentiel-a-laide-de-la-teledetection-application-au-bassin-versant-du-merdenson\/","title":{"rendered":"Valentin M\u00e9traux: Quantification de l\u2019\u00e9rosion et de la dynamique s\u00e9dimentaire dans un bassin versant torrentiel \u00e0 l\u2019aide de la t\u00e9l\u00e9d\u00e9tection. Application au bassin versant du Merdenson (Valais\/Suisse)."},"content":{"rendered":"<p><em>Valentin M\u00e9traux<\/em><br \/>\n<em>Supervisor: Prof. Michel Jaboyedoff<\/em><br \/>\n<em>Expert:\u00a0Alexandre Loye<\/em><\/p>\n<p style=\"text-align: justify\">The watershed of Merdenson dominates the villages of Voll\u00e8ges and Cries. Many major events\u00a0of debris flows are recorded on this torrent and threaten not only road and rail infrastructure, but\u00a0also the villagers of Cries.<\/p>\n<p style=\"text-align: justify\">The damage caused by debris flows have led the municipal and cantonal authorities to intervene\u00a0in the watershed to limit the spread of debris flows. This work aims to characterize the erosion in\u00a0the catchment, both in terms of volume and distribution.<\/p>\n<p style=\"text-align: justify\">The study of the distribution of erosion and its growth has called for the creation of digital<br \/>\nelevation models by stereoscopic techniques. A methodology for processing the results of stereoscopy\u00a0has also been created to make the models usable in a GIS environment. In a second step,\u00a0the evolution of the topography was compared to a set of variables, morphological, geological or\u00a0related to existing structures. Finally, an erodibility index as well as prior results have led to hypotheses\u00a0about possible developments in the medium to long term in the watershed of Merdenson.<\/p>\n<p style=\"text-align: justify\">The average volume of sediment produced has been estimated (150,000 m3\/year) for the entire\u00a0watershed of Merdenson. A comparison with estimates from previous studies validates the results\u00a0of this study and gives a ratio between the volumes of sediments carried by debris flows and those\u00a0by the normal flow. The volumes have been separated between the different parts of the study area.\u00a0The evolution of the erosion has been built from the time sequence of digital elevation models\u00a0created by stereoscopy.<\/p>\n<p style=\"text-align: justify\">In a second time, erosion and deposition of the 47 years data have been correlated with different\u00a0variables such as lithology, the shape of the channel and its slope. All these results revealed\u00a0some probable trends of the watershed and make assumptions about changes in the dynamics of\u00a0the stream thereof.<\/p>\n<p style=\"text-align: justify\">The majority of the results are confirmed by observations from the field in this work and in previous\u00a0studies. The links made between erosion and morphological variables are confirmed by other\u00a0studies and the creation of stereoscopic document is validated.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Valentin M\u00e9traux Supervisor: Prof. Michel Jaboyedoff Expert:\u00a0Alexandre Loye The watershed of Merdenson dominates the villages of Voll\u00e8ges and Cries. Many major events\u00a0of debris flows are recorded on this torrent and &hellip; <\/p>\n","protected":false},"author":1341,"featured_media":920,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","ngg_post_thumbnail":0,"footnotes":""},"categories":[73758],"tags":[51880],"class_list":{"0":"post-674","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-masters_completed","8":"tag-51880"},"_links":{"self":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/posts\/674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/users\/1341"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/comments?post=674"}],"version-history":[{"count":0,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/posts\/674\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/media\/920"}],"wp:attachment":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/media?parent=674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/categories?post=674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/tags?post=674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}