22 



LA TOUCHE : GEOLOGY OF NORTHERN SHAN STATES. 



scenery to the other is always abrupt, and the contrast is exceedingly 

 striking. AVithin a few hundred yards we proceed from the undulating, 

 somewhat tame, though pretty, scenery of the plateau, into a land of 

 deep, narrow V-shaped valleys, clothed on either hand with dense forest, 

 often of pines (P. khasija), which are never found growing naturally 

 on the Plateau Limestone. The crests of the spurs and ridges 

 dividing the valleys are equally narrow, mere knife-edges along which 

 there is often only just room for a mule track. Here the trend 

 of the streams has the closest relation with the geological structure, 

 their direction as a rule following the strike of the folds into 

 which the older Palaeozoic and Archaean rocks composing these hills 

 have been thrown ; though in some cases they cut directly across 

 the strike. The contrast between the two types of drainage affected 

 by the hill ranges and the plateau may be well seen in the region 

 drained by the Nam-panhse and its tributaries, which unite at 

 the head of the Gokteik gorge. Here there is a general tendency 

 for the streams to flow in a south-east direction, which is that of 

 the prevailing strike of the older rocks, until they reach the wall 

 of precipitous scarps forming the edge of the plateau, where they 

 collect in the Nam-Tang, which follows this line of cliffs to the 

 head of the gorge, where it joins the Nam-panhse, also flowing from 

 the north-west along the line of strike. As the train crosses the 

 great viaduct that spans the Gokteik gorge, a very fine view of 

 these contrasting features may be obtained from the railway. Imme- 

 diately to the north is seen a mass of sharp, inverted-V shaped 

 spurs, densely wooded from base to summit, while on either hand 

 is the undulating surface of the plateau, broken only by the 

 line of stupendous cliffs extending along each side of the gorge. 

 Along the western edge of the plateau, where denudation has 

 Western edge of the P ar % removed the covering of limestone, and 

 plateau. exposed the older Palaeozoic rocks beneath, the 



forms of the valleys combine the two types 

 described above. Where the streams have cut back at right angles to 

 the face of the scarp we have narrow gorges, like that of the Sedaw 

 river described above, bordered by precipitous cliffs and cirques, 

 but where they have removed the covering of limestone, as in 

 the country between the Sedaw river and the Chaung Magyi, or 

 Maddeya River, they flow in deep V-shaped valleys, in a due north 

 and south direction, which is that of the strike of the older rocks in 

 this area. 



