290 BROWN & HERON: GEOLOGY AND ORE DEPOSITS OF TAVOY. 



chaung mine, also the property of the Rangoon Wolfram Co., Ltd.. 

 at the present time. Production has been as follows : — 



Tons. 



liuii U 



191' 



•>■ 



1918 88 



The veins of all these properties are short lenses, entirely in 

 sedimentary country rock, and they have not proved of sufficient 

 length nor value to open up in a systematic maimer below horizons 

 which are easily accessible from the surface. Information concerning 

 them is therefore somewhat meagre. 



At the Rubber .Mile the general strike is about north 30° east, 

 and south 30 west and the dip averages about 75° towards the 

 south-east, with a tendency to increase towards the vertical at 

 depth. Faulting is not common, although the veins are often 

 contorted. Veins often split into two or more branches which 

 may or may not come together again. Mr. Maekilligin, the General 

 Manager of the Company, writes: — "Lenses in close proximity 

 to one another, having the same strike but not the same line of 

 strike, and winch may or may not overlap, are not uncommon. 

 They often appear to be the faulted portion of the same vein and 

 the line of fissure can often be traced for considerable distances 

 after the vein itself has pinched out." Owing to the homogeneous 

 nature of the altered sediments in the upper horizons which are 

 worked, it is often exceedingly difficult to measure the dislocations 

 produced by these fault planes or, in extreme cases, to see signs 

 • if any dislocation at all beyond the presence of the fracture. Mr. 

 Mackilligin adds — " One vein showed two distinct dip faults, 

 the more important a heave of 15 feet and a vertical displacement 

 of probably about 80 feet. The strike of the vein was north 35° 

 east and it dipped towards the south-east at 83°. The fault had 

 a strike of north 30° west, south 30° east, and its head was nearly 

 vertical." 



The general strike at Wagon North is about north 20° east, south 

 20° west and the dip is about 80° towards the east. At Thitkat- 

 chaung the general strike is between north 20° east and north 

 58° east, the deviation from the north increasing as one works 

 northwards in the concession. Dips are westerly near the surface 

 but on the veins which have been traced down, they have changed 

 either to a vertical or eastern dip at depth. 



