{"id":555,"date":"2013-09-26T14:13:12","date_gmt":"2013-09-26T12:13:12","guid":{"rendered":"http:\/\/wp.unil.ch\/risk\/?p=555"},"modified":"2013-09-26T17:06:45","modified_gmt":"2013-09-26T15:06:45","slug":"jacques-bechet-et-julien-duc-etude-et-quantification-des-processus-et-dynamique-derosion-a-draix","status":"publish","type":"post","link":"https:\/\/wp.unil.ch\/risk\/jacques-bechet-et-julien-duc-etude-et-quantification-des-processus-et-dynamique-derosion-a-draix\/","title":{"rendered":"Jacques Bechet et Julien Duc: Etude et quantification des processus et dynamique d&#8217;\u00e9rosion \u00e0 Draix"},"content":{"rendered":"<p><em>Jacques Bechet et Julien Duc<\/em><br \/>\n<em> Co-supervisors:\u00a0Prof. Michel Jayboyedoff, Alexandre Loye<\/em><br \/>\n<em> Expert: Dr. Marc-Henri Derron<\/em><\/p>\n<p style=\"text-align: justify\">The Roubine catchment located in the experimental research station of Draix (south\u00a0French Alps) is situated in the black marls formation, a substratum particularly prone\u00a0to weathering processes. Since 25 years this small watershed (0.13ha) has been\u00a0dedicated to the monitoring and the study of hillslope erosion processes at the scale<br \/>\nof the elementary gully.<\/p>\n<p style=\"text-align: justify\">Since 2007, a monitoring of topographic changes of the entire Roubine catchment\u00a0has been performed with terrestrial laser scanner (LIDAR) in order to observe and\u00a0quantify the sediment production and the evolution of the gully in terms of sediment\u00a0availability and transport capacity vs. precipitation and runoff generation. LIDAR data\u00a0have been acquired periodically based on the seasonal activity with a very high point\u00a0cloud density ensuring a resolution of the DEM at the centimeter scale. The\u00a0topographic changes over a record spanning of 4 years are analysed by comparing\u00a0the time series of LIDAR data.<\/p>\n<p style=\"text-align: justify\">Quantitative observation of the seasonal erosion activity and a fine-scale analysis of\u00a0the sediment flux contributing to an important recharge of tributary gullies and rills\u00a0with debris into the channel network could be performed. According to the transport\u00a0capacity generated by the runoff during the season, freshly-built sources of regolith\u00a0are removed at different periods of the year, forming transient deposits in the main\u00a0reach when routed downward, evolving from a transport-limited to supply-limited\u00a0regime through the year. The acquired high resolution point cloud enable to perform\u00a0a local scale morphostructurales analysis in terms of stability and sediment\u00a0production rate of the catchment slopes supplying the rills and gully with sediment.<\/p>\n<p style=\"text-align: justify\">This study aims to quantify the erosion in the Roubine\u2019s watershed, through the\u00a0comparison of the different LIDAR time series. Comparison of LIDAR Data mass\u00a0balance with the measures taken by the limnigraph located at the end of the\u00a0catchment was processed. Our results show that Terrestrial laser scanner is a\u00a0relevant method to quantify the erosion. The results have been used for the\u00a0realization of a gully\u2019s analogical model in laboratory.<\/p>\n<p style=\"text-align: justify\">These experiments attempt to document toward a better understanding of erosion\u00a0processes, which affect the badland-type terrain, by illustrating the mode of sediment\u00a0production and temporal storage\/entrainment in the adjacent slopes of the Roubine\u00a0major gullies.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Jacques Bechet et Julien Duc Co-supervisors:\u00a0Prof. Michel Jayboyedoff, Alexandre Loye Expert: Dr. Marc-Henri Derron The Roubine catchment located in the experimental research station of Draix (south\u00a0French Alps) is situated in &hellip; <\/p>\n","protected":false},"author":1341,"featured_media":913,"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":[29716],"class_list":{"0":"post-555","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-masters_completed","8":"tag-29716"},"_links":{"self":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/posts\/555","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=555"}],"version-history":[{"count":0,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/posts\/555\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/media\/913"}],"wp:attachment":[{"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/media?parent=555"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/categories?post=555"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.unil.ch\/risk\/wp-json\/wp\/v2\/tags?post=555"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}