PHYSICAL FEATURES. 55 



Part 2. — Notes on the Geology of the Western Part of Myingyan 

 District and of a small area in the north of Magwe District , 

 Upper Burma, 



The physical features of the western part of Myingyan and the 

 northern parts of Magwe districts, upper 



Physical features of the _ . 



area examined : Burma, may be roughly described as a number 



hills of aoticiine with of ranges of hills having an approximately 



intervening plains. __ 



N. N. W. and S. S. E. direction and between 

 these ranges of hills more or less flat country. The hills which 

 are due to a number of anticlinal folds are formed of miocene 



and pliocene strata, the miocene beds in some 



Hlils composed of 



pliocene and miocene cases forming the centre of the hills with 



strata. , # 



pliocene beds along the sides or the anticlinal 

 arch may not be sufficiently raised or sufficiently denuded for the 

 miocene beds to be exposed and then the hills are composed of 

 pliocene sandstones only. The plains are mostly covered by recent 

 deposits. 



The ranges of hills composed of miocene beds are, however, very 



different in appearance from those composed of 



Hills of miocene beds ,. . A „ _ t . , 



different in aspect from pliocene sandstones. Ihe hrst are steep and 



those of pliocene age. . . e ,. .. J , 



rise sharply from the surrounding country, and 

 being composed of alternate beds of sandstone and shale which 

 unequally resist weathering, the form of the hills is governed by the 

 weathering of these beds when dipping at various angles ; where the 

 beds are steeply inclined the hills take the form of a number of 

 narrow parallel ridges, but where they have only a gentle dip the 

 hills have a dip slope on one side and a steep scarp on the other. 

 In contrast with the hills composed of miocene beds those which are 

 formed of pliocene beds rise, as a rule, but slowly from the surround- 

 ing country and they tend to form broad plateau-like elevations with 



only a gentle slope to the sides. On both kinds 

 Hilly ground barren. f hills the rocks are almost everywhere 



exposed the ground being quite barren and little 



( 55 



