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Table 2 Mineral assemblages of 2014 primary eruption, October rain-triggered lahar, and April ROS-triggered lahar deposits identified by XRD

From: Lahar characteristics as a function of triggering mechanism at a seasonally snow-clad volcano: contrasting lahars following the 2014 phreatic eruption of Ontake Volcano, Japan

Sample name Description Qz Pl Crs Py Gp Anh Alu Prl Sme Ilt Kln I/S Chl
September 2014 primary deposits
 On-1 Ashfall (Tanohara parking lot; bulk) + + + + + + +   + + +   
 On-64 Ashfall (Ishimuro Sanso hut; lower part) + + + + + + + + +   +   
 On-65 Aggregates of ashfall (Ishimuro Sanso hut; upper part) + + + + + + + +   + +   
 On-44 Ash cloud deposits (Akagawa, upstream end) + + + + + + + + + + +   +
October 2014 rain-triggered lahar
 On-13 Cohesive debris flow deposits (Nigorigawa, downstream end) + + + + + + + + + + + + +
 On-18 Cohesive debris flow deposits (Akagawa, overbank facies) + + + + + + + + +   + + +
 On-34 Cohesive debris flow deposits (Akagawa, bottom part) + + + + + + + + + + +   +
 On-45 Cohesive debris flow deposits (Akagawa, upstream end) + + + + + + + + + + + + +
April 2015 rain-on-snow-triggered lahar deposits (mud drape)
 On-21 Rain-on-snow lahar deposits (Akagawa) + + + +   + + + + + + + +
  1. Qz quartz, Pl plagioclase, Crs cristobalite, Py pyrite, Gp gypsum, Anh anhydrite, Alu alunite, Prl pyrophyllite, Sme smectite, Ilt illite, Kln kaolin group minerals (7Å), I/S illite/smectite mixed layer, Chl chlorite