THE KAMPA SYSTRM. 
55 
limestone to the top of the sandy sliale is based on the section 
exposed on the right bank of the Kampa gorge at about one mile 
above the fort. This is shown on PI. lo. 
The beds on the ridge on the north side of the stream are very 
much disturbed, the line of iunction between 
Faults. ' . ^ 
the youngest Tertiary shale and the overlying 
Operculina limestone being a fault. Numerous other faults occur 
both along and across the strike of the beds ; a prominent fault of the 
latter type is shown on PI. 12, fig. i. 
This fault, which is exactly followed by the path over the ridge 
has resulted in very considerable horizontal displacement, and has 
brought the Operculina limestone, on the east of the faulty into line 
with the upper part of the Cretaceous limestone (Vola horizon) on 
the west. 
All this disturbance has greatly complicated the sections through- 
out the ridge ; on the hills to the north of the Dzongbuk La, the 
watershed between the Kampa and Tatsang streams, the beds 
appear to have been inverted, for the ferruginous sandstone is found 
underlying the third scarp limestone. This locality is one of con- 
siderable interest, for at the point where the road ascends to the 
Dzongbuk La an outcrop of Alveolina limestone was found dipping 
at a high angle to the north, under dark shales which were at first 
assumed to represent the beds above the Orbitolites limestone in the 
section already described. The Dzongbuk limestone, however, 
differs from that seen nearer Kampa dzong in 
Alveolina limestone. , 
being composed almost entirely of Alveolina. 
It was at first mistaken for nummulitic limestone ^ and the error was 
only discovered when a thin slice of the rock was put under the 
microscope. 
Unfortunately this section is complicated by disturbance as well 
as obscured by debris, and being, under the circumstances prevailing 
at the time it was visited, very difficult of access, it was not examined 
' See Rec. Geol. Surv. Jnd., Vol. XXXII, pp. 165 and 171, where the rock is 
erroneously called nummulitic limestone. 
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