98 M1DDLEMISS: PHYSICAL GEOLOGY OF SUB-HIMALAYA. 



as against a cliff. The Nahan sandstone here is of great width, 

 holding entire possession of the Sub-Himalayan zone, and it continues 

 so as far as the Balia ravine (61) which descends from Naini Til. The 

 main boundary up to this point continues in a fairly straight line 

 cutting the Naini TaM-K31adhungi road at Bijaun village (62), the 

 Nehal R. near Nehalpur, and thence crossing a little S. of Balne 

 Kh3n and following parallel to and a little north of the Nalena R. (63) 

 to ]61e kot. It is lost to view eventually in the Balia N. by a cover- 

 ing of superficial gravels. 



The disposition of the Nahans appears to be that of an inverted 

 synclinal, the axis of which runs along the ridge south of the Nalena 

 valley. Whether this synclinal is broken along the axis, or not, by a 

 fault, there are no data to say. North and south of it the beds harden 

 considerably, and apparently by degrees ; whilst along the axis they 

 are soft and typically the uppermost beds of the Nahan stage. There 

 is thus an inversion of the Nahans immediately south of the main- 

 boundary fault. 



At the Balia ravine this arrangement is broken by a cross-fault, a 

 lateral wrench of the strata, plainly indicated by the swerving round 

 of the dip towards it in the neighbourhood of the Nalena bridge on the 

 bridle road to Naini Ta*l from R£niba"gh. The cross-fault follows a line 

 very nearly coincident with the Balia ravine, as far as the suspension 

 bridge at Ra*nib£gh (64). The main boundary by this fault is thrown 

 southwards on the east side of it, so that the continuation of the 

 main boundary, instead of passing a little south of Bhim Ta*l (as it 

 would if undisturbed by the cross-fault), takes a new departure near 

 the suspension bridge and follows the course of the Gola R. for 

 some miles up stream. This general statement with regard to the 

 Nahans in this neighbourhood will be sufficiently intelligible if the 

 map with the dips marked on it be studied in conjunction with it. It 

 must be inferred, however, that the lateral wrench of the strata along 

 the cross-fault has been supplemented along its southern extension 

 near Rcinibcigh by an up and down movement, the upthrow being 

 on the east side ; for the main boundary along the east and west 

 ( 156 ) 



