LA TOUCHE : GEOLOGY OF NORTHERN SHAN STATES. 



Jurassic age. In justice to Dr. Noetling, however, it must be 



admittsd that none of the limestone bands appear at all on the 



route which he followed, and that the sandstones themselves seem 



to be almost without fossils. 



Regarding the Tertiary formation, with its coal seams, Dr, 



™ .. , Noetling was strongly inclined to the opinion 



lertiary formation. , , , . , , , r 



that these beds had been preserved by being 



let down between his imaginary faults, and that they were con- 

 fined to those valleys which run from south-west to north-east. 

 Recent surveys of these coal basins, however, have shown that the 

 silts in which the coal seams occur were deposited after the present 

 system of hill and valley had been carved out ; also that the 

 valleys to which they are confined radiate from the highest ground 

 on the plateau, and have no common direction. Dr. Noetling 

 appears to have been in considerable doubt regarding the age of 

 these beds, for in his list of formations he alludes to them as 

 ' probably younger Miocene,' whereas elsewhere (Op. cit., p. 106) he 

 speaks of them as of late Tertiary age. The latter supposition is 

 probably correct, since the only fossils associated with the coal 

 seams possess a very recent geological aspect. 



The pebbles of ' porphyry ' mentioned by Dr.. Noetling as being 

 p ^ found in the bed of the Namma river are 



derived from rocks belonging to the Bawdwin 

 volcanic series, which are in situ on the southern side of the valley 

 higher up. 



During the field-season of 1899-1900 a systematic survey of the 

 Northern Shan States was begun by my 



Traverse of 1899-1900. AT 8 * J 



colleague Mr. r. JN. Datta and myseli, with a 

 traverse along the cart-road and the railway line then in course 

 of construction from Mandalay to the Sal ween. The results of 

 our investigations were published separately in the General Report 

 of the Geological Survey for that year, and as a natural conse- 

 quence there are certain discrepancies in the interpretations which 

 each of us gave to our observations. Moreover, the open season 

 was no more than long enough to enable us to journey directly 

 across the plateau and back again ; and as the railway and cart- 

 road avoid the broken ground as far as possible, more than one 

 formation of great importance escaped notice altogether or was very 

 inadequately described. Thus there are many imperfections in 

 these preliminary reports, and in some cases serious alterations and 



