1853.] Report on the Geological Structure of the Salt Mange. 351 



rock in great part of the central district of the Salt Range. As far 

 west as JNoorpoor, it is in relation with Devonian rocks ; but between 

 this and Koofree, the carboniferous rocks intervene. In this neigh- 

 bourhood the Oolitic rocks appear at the base of the Eocene forma- 

 tion, and as we proceed westward, separate it more and more widely 

 from its eastern associates. 



At the west end of the Sam Sikesur valley all the strata form- 

 ing the high ridge of mount Sikesur are tilted up at a high angle. 

 Along the foot of its scarped or S. S. E. side all the rocks are very 

 much disturbed ; but in the escarpment itself great regularity pre- 

 vails, the nummulite limestone forming its summit and N. N". W. 

 side till near its base, where it is covered up by conformable Mio- 

 cene sandstones, &c. 



Erom mount Sikesur on to within two miles of the Indus the 

 nummulite limestone occurs uninterruptedly ; but though of greater 

 real thickness than to the eastward, makes comparatively little 

 show, owing to the high angle (45 to 50° ) at which it dips to the 

 north-east under the Miocene rocks. 



In the disturbance which the strata in the neighbourhood of 

 Maree have undergone, the nummulite limestone seems to have been 

 entirely removed, but on crossing the Indus to the Kalibagh hill, 

 beds of it again appear. 



These stretch round into the Chichalee Eange, and, as seen in the 

 Chichalee Pass, have a thickness of upwards of one thousand and 

 three hundred feet. In this Eange, as in the Salt Eange, the num- 

 mulite limestone appears in bold white cliffs forming the summit 

 of its scarped or south-east side, and the formation may be traced 

 down to within six miles of the Koorum river, where it thins out 

 under Miocene sandstone. 



It does not appear in the upper part of the Kaffir Kote Eange, 

 though from the researches of Captain Vicary, it is known to occur 

 to a considerable extent in the southern part of the Sooliman and 

 Hala ranges. Capt. Grant too, in Cutch, has described a series of 

 beds of nummulite formation extending over a space of about thirty 

 miles, many of the fossils obtained from which are identified with 

 those we have found in the Salt Eange. 



During the hot weather of 1851 we detected nummulite limestone 



2 t 2 



