48 GRIMES : MY1NGYAN, MAGVVE AND PAKOKKU DISTRICTS. 



maximum in block 58 N, about three miles south of Singu, where & 

 patch of lower miocene beds is exposed, then there is a slight 

 sinking of the axis between this block and the Irrawaddi. On the 

 other side of the river the axis is at first apparently horizontal, and 

 then it very slowly and gradually rises to a maximum at Yenangyat, 

 where the lower miocene beds are again at the surface ; from here 

 towards the north it sinks again, at first gradually, and then more 

 rapidly as far as block 5, where it again begins to rise so rapidly 

 that, in the south-west corner of block 2, the first oil sand of the 

 lower miocene is close to the surface. The rise then continues 

 slowly with slight oscillations, to as far as where the road from 

 Sabe to Gonledaing crosses the hills, and at this place the first oil 

 sand is 250 feet above the bottom of the Chaung, but after this the 

 anticlinal axis sinks continually as far as I have been towards the 

 north, 



The beds in these Singu and Tangyi hills are folded in an 

 unsymmetrical anticlinal arch, the dip on the east side being very 

 much steeper than on the west side. Near the southern end of the 

 Singu hills, close by Trinzan, we find the pliocene beds on the east 

 side of the anticline with a dip of 36 to the east, and on the west 

 side it is only a very low westerly dip. As one goes north the 

 anticlinal axis rises and so the dips steepen, but they are always much 

 steeper on the east side than on the west, thus west of Teingan 

 we find in the pliocene beds a dip of 6o° on the east side and only 

 low dips on the west side. In the section from Kyeni westwards, 

 where we have miocene beds exposed in the centre of the anticline, 

 we have, advancing west, first, pliocene beds with a steep dip and 

 then miocene beds, the uppermost of which has a dip of 69 to the 

 east; this dip decreases somewhat towards the centre of the anticline, 

 where the beds turn over rather sharply to a dip of io° west, 

 which gradually increases to 27 , and then decreases until, at the 

 western boundary of the miocene beds, it is only 15 . A little 

 farther north, where the anticlinal axis rises to its first maximum at 



i 48 ) 



