250 MIDDLEMISS: GEOLOGY OF HAZARA AND BLACK MOUNTAIN. 



masses or sills of gneissose-granite and dykes of a plagioclase-augite 

 rock (see p. 51). None of the metamorphosed Infra-Trias or Tanols 

 are known to be represented. 



These rocks from a petrographical point of view have been de- 

 scribed in the chapter on the stratigraphical elements, and I shall 

 now give some account of the rocks (as briefly as possible) shewing 

 their geotectonic inter-relations. 



The first section I shall take (indicated in the margin) is by way 

 of linking up the observations in Tanawal with 



Section from near , T> , . __ . _. ,, ... 



Budhauruh to Derbund. tne Black Mountain. Budhauruh lies north of 

 the Doodha mountain Tanols, and the section 

 from it to Derbund via Lalo Gulee is as follows : — As far as the latter 

 place it crosses somewhat diagonally over the outcropping edges 

 of the beds whose strike is generally N.W.— S.E. About the posi- 

 tion of the first " h " of Budhauruh there are dykes of decomposed 

 trap which are continuous with those near the " n " of Budgiran. 

 They occur apparently interbedded with quartz-schists and with a 

 single thin layer of white crystalline marble. Further on, nearly 

 as far as Sunvai, the rocks become more markedly metamorphic 

 and schistose, with a few trap dykes, and with large quantities of 

 graphitic schists streaking the hill-sides with black. With them is 

 some haematite, and an efflorescence of alum in thin lines near the 

 stream below Sunvai. 



At Sunvai there occur some very thick beds of white and buff- 

 coloured crystalline limestone, which outcrop up the hill-side in a 

 north-westerly direction. On the road north-east of the " i " of Sunvai, 

 the first bed of very much decomposed gneissose-granite sets in. It 

 is not very coarsely crystalline and is not porphyritic. It is very 

 distinctly foliated in places. 



Then follows, as far as the second little gulee on the road north- 

 west of the " S " of Sunvai, a very irregular plexus of fine bands 

 of trap, gneissose-granite, and mica-schist, alternating with each 

 other. Individually mapping these bands, except diagrammatically? 

 would be impossible. 

 ( 250 ) 



