312 LA TOUCHE: GEOLOGY OF NORTHERN SHAN STATES. 



greater preponderance of clays, generally of a yellow colour ; 

 but some, in the neighbourhood of Man-Se (Loc. 2, H 

 1), are pure white, resembling kaolin, and may perhaps 

 prove to be of economic value as 



Conglomerates. , , -r» i r i 



pottery clays. Beds of conglomerate 

 are also more numerous, made up of pebbles and boulders 

 of quartz and crystalline rocks derived from the hills 

 _ . . , to the east. As in the Lashio 



Position of coal _ . .. . . . 



seams, field the coal seams appear to be 



confined to the lower portion of 

 the group, but there is much more variety in the dips, 

 and the outcrop of the seams is not confined to the 

 bed of the rivers. The general dip is low, about 20 

 degrees on an average, and is directed towards the 

 north-west at the western end of the field and to the 

 north-east at the opposite end (Plate 16) ; but there are 

 considerable local variations, due perhaps to the underground 

 denudation of the limestone floor. The northern boundary 

 is obscure, and may be partly faulted, but the appear- 

 ance of faulting may be due to the same cause as the 

 unevenness of the dips. The southern boundary is a 

 natural one. 



(iv) Below the Namma field the river races through a deep 



narrow gorge in the limestone to its junction with the 

 Namyau at Se-In, but about three 'miles below the 

 main area it passes through a small oval basin of the 

 Tertiary rocks extending for about 5 miles along its 

 banks and about half a mile broad. No outcrops of 

 coal were found in this outlier, and the rocks exposed 

 have not been described. It may have been connected 

 at one time with the Namma field, but it is quite as 

 likely to have been an independent basin of deposition. 



(v) The Man-sang field. This basin is situated in the State 



of South Hsenwi, about 7 miles to the west of Mong 

 Yai, the capital of the State, and about 16 miles to 

 the south-east of the Namma field (H 3). It covers 

 an area of about 13 square miles, but the southern and 

 south-eastern boundaries are very ill 



Lithological characters. . _ . , . < i i 



defined, being concealed by recent 

 clays. The rocks are similar to those of the Lashio 



