96 BLANFORD : GEOLOGY OF WESTERN SIND. 



narrow cleft with vertical sides, so filled up by immense masses of lime- 

 Goro-e in Khirthar stone that it is impossible to climb through the 

 limestone. ffore-e. The thickness of the main bed of Khirthar 



limestone does not appear to be more than 1,200 feet, or considerably less 

 than it is farther north. The underlying beds are well seen west of the 

 main range in Kelat. The range may be crossed either north or south of 

 the gorge : the northern pass, which is the lower of the two, but very 

 steep, is known as Kapwi; the southern as Shekalwi. The section 

 seen on the Gaj, west of the frontier, which has been already given in a 

 general form in Chapter III, 1 is partly seen in the bed of the Gaj 

 for a distance of between 3 and 4 miles from the frontier, and the con- 

 tinuation is exposed west of the river (see Plate IV) . The following 

 are additional details of this section. 



The massive nummulitic limestone, (l) 2 forming the high ridge of the 



Section of lower Khir- Khirthar, contains, towards the base, some layers 



thai- group on Gaj river. £ c ] a y S and s h a i es# The lower portion of the 



limestone is dark coloured as a rule, and abounds in nummulites, 

 amongst which a large planulate species (N. lyelli ?) is conspicuous. A 

 large Alveolina, is also common. Below these limestones there is a 

 considerable thickness of shales and clays, (2) calcareous in parts, and 

 containing nummulites, which weather out in such quantities as to cover 

 the surface, and which are beautifully preserved. These beds are usually 

 dark olive in colour ; and although they are soft and crumbling on the 

 surface, they are probably a hard argillaceous limestone below. Beneath 

 these shales is a bed of hard limestone (3) at least 60 feet thick, the upper 

 portion being homogeneous, grey, and in thin bands, unfossiliferous as 

 a rule, although a crab was obtained from it, the lower part abounding in 

 nummulites, seen in section on the weathered surface. This hard bed 

 is conspicuous from the top of the range, whence it is seen to dip under 

 the massive Khirthar limestone. 



1 See p. 41. 



2 These numbers refer to those in the section, (PI. IV), and are the same as those o£ 

 the beds enumerated at page 41, Chapter III. 



( 96 ) 



