YENANGYOUNG. 91 



from west along the slopes of Minlindoung towards the east, covered 

 by beds of the Irawadi series. The dip on the western side is 

 about 30 , but it becomes flatter and flatter towards the centre 

 forming the reverse on the eastern side. 



These sections prove conclusively that the angle of the arch of 

 the anticlinal changes in proceeding from the south towards north ; 

 it is very flat near Minlindoung, but becomes more and more com- 

 pressed towards the middle of the oil field, whence it again slowly 

 flattens out. The natural consequence of this change in the arch of 

 the anticlinal must be a rise of the crest from its southern end 

 towards the centre and a fall from thence towards its northern end. 

 The lateral pressure which has produced the anticlinal did not act 

 equally throughout its length : at some places it acted more forcibly, 

 at others with less energy. At the former places the beds were more 

 compressed than at the latter, and naturally deeper strata were 

 raised closer to the surface than it was the case at places of smaller 

 energy in the lateral pressure. The natural result of this different 

 energy must be the production of a dome or turtleback-like elevation, 

 the slope of the surface of which is directly proportional to the 

 energy of the lateral pressure. 



C. — The sections of the drilled wells. 



From the records of strata, as found in the deep wells, as I received 

 them from the boring engineers, I have constructed the sections on 

 plates XIII, XIV, making allowances for the level of each well, 

 in order to obtain as accurate a position of each bed above sea level 

 as possible. A few words must, however, be said about the great 

 difficulties in the way of comparing these boring registers, when 

 there were no other means of identifying and correlating certain 

 beds but such vague terms as have been used by the drillers, and 

 the depth at which such beds were found from the surface. It 

 is also almost certain that the various drillers have used slightly 

 different terms to designate the lithological character of one and 

 the same bed, a discrepancy which of course increased the difficul- 

 ties still more. 



( 137 ) 



