Estimate of the debris-flow entrainment using field and topographical data

Abstract The entrainment of material is a common process in debris-flow behaviour and can strongly increase its total volume. However, due to the complex nature of the process, the exact mechanisms of entrainment have not yet been solved. We analysed geomorphological and topographical data collected in 110 reaches of 17 granular debris flows occurred in the Pyrenees and the European Alps. Four governing factors (sediment availability, channel-bed slope, channel cross section shape and upstream-contributing area) were selected and defined for all the 110 reaches. One dataset of the resulting database was used to develop two models to estimate the erosion rates based on the governing factors: a formula derived from multiple linear regression (MLR) analysis and a decision tree (DT) obtained from J48 algorithm. The models obtained using these learning techniques were validated in another independent dataset. In this validation set, the DT model revealed better results. The models were also implemented in a torrent (test set), where the total debris-flow volume was known and two empirical methods (available in literature) were applied. This test revealed that both MLR and DT predict more accurately the final volume of the event than the empirical equations for volume prediction. Finally, a general DT was proposed, which includes three governing factors: sediment availability, channel-bed slope and channel cross section shape. This DT may be applied to other regions after adapting it regarding site-specific characteristics.

[1]  Ian H. Witten,et al.  The WEKA data mining software: an update , 2009, SKDD.

[2]  Richard M. Iverson,et al.  Flow of variably fluidized granular masses across three‐dimensional terrain: 2. Numerical predictions and experimental tests , 2001 .

[3]  Dieter Rickenmann,et al.  Beurteilung von Murgängen , 1995 .

[4]  Matthias Jakob,et al.  The role of debris supply conditions in predicting debris flow activity , 1999 .

[5]  C. Lee,et al.  The role of the sediment budget in understanding debris flow susceptibility , 2009 .

[6]  M. Papa,et al.  Critical conditions of bed sediment entrainment due to debris flow , 2004 .

[7]  Philippe Coussot,et al.  Recognition, classification and mechanical description of debris flows , 1996 .

[8]  Shiuan Wan,et al.  A knowledge-based decision support system to analyze the debris-flow problems at Chen-Yu-Lan River, Taiwan , 2009, Knowl. Based Syst..

[9]  Tom Fawcett,et al.  An introduction to ROC analysis , 2006, Pattern Recognit. Lett..

[10]  A. Bárdossy,et al.  Generating of areal precipitation series in the upper neckar catchment , 2001 .

[11]  J. Muñoz.  Evolution of a continental collision belt: ECORS-Pyrenees crustal balanced cross-section , 1992 .

[12]  Ian H. Witten,et al.  Data mining: practical machine learning tools and techniques, 3rd Edition , 1999 .

[13]  Ian H. Witten,et al.  Chapter 1 – What's It All About? , 2011 .

[14]  E. Gabet,et al.  A morphometric analysis of gullies scoured by post-fire progressively bulked debris flows in southwest Montana, USA , 2008 .

[15]  Anne Mangeney,et al.  Geomorphology: Landslide boost from entrainment , 2011 .

[16]  K. M. Scott,et al.  Downstream dilution of a lahar : transition from debris flow to hyperconcentrated streamflow. , 1985 .

[17]  C. Graf,et al.  Field and monitoring data of debris-flow events in the Swiss Alps , 2003 .

[18]  D. Rickenmann,et al.  Erosion by debris flows in field and laboratory experiments , 2003 .

[19]  Markus N. Zimmermann,et al.  The 1987 debris flows in Switzerland: documentation and analysis , 1993 .

[20]  M. Borga,et al.  Hydrometeorological controls and erosive response of an extreme alpine debris flow , 2009 .

[21]  Oldrich Hungr,et al.  Quantitative analysis of debris torrent hazards for design of remedial measures , 1984 .

[22]  M. Jakob,et al.  Debris-flow Hazards and Related Phenomena , 2005 .

[23]  Padhraic Smyth,et al.  From Data Mining to Knowledge Discovery in Databases , 1996, AI Mag..

[24]  R. Guthrie,et al.  An examination of controls on debris flow mobility: Evidence from coastal British Columbia , 2010 .

[25]  O. Hungr,et al.  A model for the analysis of rapid landslide motion across three-dimensional terrain , 2004 .

[26]  D. F. VanDine,et al.  Debris flows and debris torrents in the Southern Canadian Cordillera , 1985 .

[27]  Michel Jaboyedoff,et al.  Sediment budget monitoring of debris-flow and bedload transport in the Manival Torrent, SE France , 2012 .

[28]  Brian W. McArdell,et al.  Sediment transfer patterns at the Illgraben catchment, Switzerland: Implications for the time scales of debris flow activities , 2011 .

[29]  Vincenzo D'Agostino,et al.  Estimation of debris‐flow magnitude in the Eastern Italian Alps , 2004 .

[30]  Giovanni B. Crosta,et al.  Numerical modelling of entrainment/deposition in rock and debris-avalanches , 2009 .

[31]  Allen Bateman,et al.  Application of FLATModel, a 2D finite volume code, to debris flows in the northeastern part of the Iberian Peninsula , 2008 .

[32]  Allen Bateman,et al.  Debris-flow susceptibility analysis using fluvio-morphological parameters and data mining: application to the Central-Eastern Pyrenees , 2013, Natural Hazards.

[33]  M. Degetto,et al.  AN ESTIMATE OF THE SEDIMENTS VOLUME ENTRAINABLE BY DEBRIS FLOW ALONG STROBEL AND SOUTH PEZORÌES CHANNELS AT FIAMES ( DOLOMITES , ITALY ) , 2012 .

[34]  Kaare Høeg,et al.  Erosion and morphology of a debris flow caused by a glacial lake outburst flood, Western Norway , 2008 .

[35]  M. Jakob,et al.  The significance of channel recharge rates for estimating debris‐flow magnitude and frequency , 2005 .

[36]  Scott McDougall,et al.  Entrainment of material by debris flows , 2005 .

[37]  J. Moya,et al.  Results and experiences gathered at the Rebaixader debris-flow monitoring site, Central Pyrenees, Spain , 2014, Landslides.

[38]  L. Franzi,et al.  A statistical method to predict debris flow deposited volumes on a debris fan , 2001 .

[39]  J. E. Gartner,et al.  Empirical models to predict the volumes of debris flows generated by recently burned basins in the western U.S. , 2008 .

[40]  S. Egashira,et al.  Experimental study on the entrainment of bed material into debris flow , 1999 .

[41]  Christian Scheidl,et al.  The use of airborne LiDAR data for the analysis of debris flow events in Switzerland , 2008 .

[42]  R J Fannin,et al.  An empirical-statistical model for debris flow travel distance , 2001 .

[43]  N. Mangold,et al.  Erosion and mobility in granular collapse over sloping beds , 2010 .

[44]  R. Fannin,et al.  Debris flows: some physical characteristics and behaviour , 1993 .

[45]  Richard M. Iverson,et al.  Elementary theory of bed‐sediment entrainment by debris flows and avalanches , 2012 .

[46]  Richard M. Iverson,et al.  Positive feedback and momentum growth during debris-flow entrainment of wet bed sediment , 2011 .

[47]  George Hripcsak,et al.  Technical Brief: Agreement, the F-Measure, and Reliability in Information Retrieval , 2005, J. Am. Medical Informatics Assoc..

[48]  Leo Breiman,et al.  Classification and Regression Trees , 1984 .

[49]  Yongyong He,et al.  Debris flow erosion and deposition in Jiangjia Gully, Yunnan, China , 2005 .