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Table 2 Mineral assemblages of altered rock fragments in the volcanic ash

From: Mineralogical study on volcanic ash of the eruption on September 27, 2014 at Ontake volcano, central Japan: correlation with porphyry copper systems

Sample name

Mineral assemblagesa

Alterationb

Colorc

Si

Ab

Kfs

Kao

Mus

Pyl

Alu

Anh

Pyr

Chr

Rul

Pl

Ano

Px

Bi

Grt

glass

141014 coarse-6

*

  

*

    

*

  

*

*

*

  

*

Partly

nd

Med3-4-7

  

*

        

*

     

Partly

nd

Coase-1

*

       

*

 

*

      

RS

OW

Coarse-11

*

         

*

      

RS

OG

Coarse-18

*

       

*

 

*

      

RS

Tr

Coarse-2

*

  

*

    

*

        

AA

OW

Coarse-12

*

  

*

  

*

 

*

        

AA

OW

Coarse-13

*

  

*

    

*

        

AA

OG

Coarse-14

*

     

*

 

*

        

AA

OG

Coarse-16

*

    

*

  

*

        

AA

OG

Coarse-17

*

    

*

  

*

        

AA

Tr

Coarse-4

*

 

*

 

*

    

*

       

Ser

TBG

160223 Coarse 4-3

*

   

*

   

*

        

Ser

OW

Coarse-6

*

*

*

              

PA

TW

Med3-5-10

 

*

*

    

*

      

*

  

PA

nd

Med 1-2

*

 

*

     

*

      

*

 

PA

nd

  1. aMineral names are abbreviated as: Si: silica mineral, Ab: albite, Kfs: potassic feldspar, Kao: 7 Å-kaolin-group mineral, Mus: muscovite, Pyl: pyrophyllite, Alu: alunite, Anh: anhydrite, Pyr: pyrite, Chr: chlorite, Rul: rutile, Pl: plagioclase, Ano: anorthoclase, Px: pyroxene, Bi: biotite, and Grt: garnet
  2. bPartly: partly altered volcanic rock; RS: residual silica; AA: advanced argillic; Ser: sericite; PA: potassic alteration
  3. cOW: opaque white-colored; OG: opaque gray-colored; TW: translucent white-colored; TBG: translucent brownish gray-colored; Tr: transparent; nd: no data