132 GRIESBACH : GEOLOGY OF THE CENTRAL HIMALAYAS. 



the process of folding which the Himalayan rocks have undergo; e, 

 the rocks of the permian and lower trias have suffered the greatest 

 amount of contortion, chiefly perhaps, because the softer rocks, 

 shales and thin-bedded limestones of the lower and middle trias have 

 yielded to side-pressure much more than did the rigid dolomites and 

 limestones of the rhaetic. They are found to generally occupy 

 a narrow synclinal strip inclosed between one or more great anti- 

 clinals. Similarly, the Spiti shales frequently are found crushed 

 into a narrow synclinal between the trias and upper rhaetic. The 

 palaeozoic rocks, which form the zone nearest the metamorphic centre, 

 generally are seen as one or more gigantic antklinals. 



The fault (see sections) which I have described as running in a 

 north-west to south-east direction from the Dhauli Ganga to the 

 Milam passes, may be traced almost without interruption and is seen 

 to lose rise If near the Uttardbura pass, where the throw is quite 

 insignificant. 



In the section between the Marchauk pass and the Ma Rhi La, the 



palaeozoic rocks are seen east of the former 



B&ra Hot i. Section. 



pass, to dip about 45 towards the triassic 

 system, which has been let dawn by the great Painkanda fault to 

 below the level of the palaeozoic rocks. The latter consist there of 

 the flesh-coloured quartzites and green shales of the upper silurian, 

 overlaid by the carboniferous, whilst the white quartzite (8) crowns 

 the jagged peaks of the Marchauk. Further to the south-east, how- 

 ever, I observed the lowest silurian cora /-hmeslones with fossils to 

 underlie the upper silurian shales and quartzites, and to form with 

 them a great anticlinal arch at the Chor Hali pass ; near the small 

 glacier north of it the beds are very little inclined towards the east, 

 whereas further away from the centre of the arch, and in the proximity 

 of the fault, the beds have a dip of 50 and more to the north-east 

 by east. 



The whole east slope of the Marchauk and Chor Hoti range is 

 obscured by masses of debris and moraine matter, but numerous deep 

 ravines have been scooped out through the talus down to the rocks 

 ( 132 ) 



