102 GR1ESBACH : GEOLOGY OF THE CENTRAL HIMALAYAS. 



on the left side of the Dhauli near Patalpdni and forms also the left 

 side of the Ganes river, from near the camping ground on that river 

 on the road to the Niti pass to the main range near the Gw^ldankar 

 camping ground. 



The section of the lower Silakank slopes near Pethathali camp- 

 Section of the Petha- in & ground is almost undisturbed, if we except 

 thali ravine. jointing and local crushing and the beds of 



the lower palaeozoics dip steadily to the north-east at an angle 

 varying from 30 to 40 . I found in descending order the following 

 beds : 



UPPER SILURIAN. 



Thickness, 

 feet. 



Towards the top very hard dirty pinkish grey and dark quartzite, 

 alternating with greyish green, micaceous shales, phyllitic. The 

 quartzite beds are often replaced by dark CWMimestone. The 

 greenish shales show fucoid markings and all the beds yield nu- 

 merous fossils, which are best preserved in the Coral limestone. 

 Orthis sp. ......... 



Lower down the shale beds decrease in frequency, and the pink or 

 rather dirty flesh-coloured quartzite predominates and its beds are 

 thicker ....... . 



Flesh-coloured quartzites, alternating with shales and Coral lime- 

 stone. The shales with fucoid markings are more frequent near 

 the top, whereas lower down the limestone beds divide the 

 quartzite and they yield many fossils, Corals, Orthis, etc. 



About io' of Coral limestone followed by flaggy beds of flesh- 

 coloured quartzite divided by calcareous Coral beds . , 



Massive beds of CWa/ limestone, alternating with thick beds of flesh- 

 coloured quartzite, which latter are associated with thin partings 

 of green shaly beds ........ 



Quartzite beds alternating with greenish grey silicious shales, which 

 latter show cleavage. Fucoid marks are chiefly found on the 

 shales, whereas in the quartzite Corals, Encrinites and Brachiopods 

 abound. The shales increase in thickness higher up . . 



Shales, divided by a thin bed of quartzite ..... 



Flaggy bed of quartzite . ....... 



Grey, very friable shales with thin partings of quartzite . 



Quartzite in thick flaggy beds, alternating with very friable, grey 

 shales with fucoid markings. Corals, Encrinites and Brachiopods 

 in the quartzite ......... 



710 



22 



40 



38 



280 



2 

 I 



6 



35 



Total 



i,i34 



( J02 ) 



