110 WYNNE : GEOLOGY OF THE SALT RANGE IN THE PUNJAB. 



In other places where the Nahan beds have not been recognised, the 

 lowest rocks of the Salt Range tertiary sandstone series are slightly 

 calcareous, often of the nature of the pseudo-conglomeratic gravelly- 

 looking beds found higher in the formation. Their colour is pale purple 

 or dull grey, passing rapidly upward into soft coarse sandstones of green- 

 ish or dull brownish and grey colours, containing locally crocodilian 

 bones, teeth, jaws, scutes, &c., and pieces of exogenous fossil timber in 

 considerable numbers. 



Above these beds greyer sandstones prevail, and red clays or shales 

 increase in quantity upwards, associated with occasional layers of pseudo- 

 conglomerate and lumpy calcareous purple clay until the red beds pre- 

 dominate so as to form a marked "red clayey zone^^ with indefinite 

 upper and lower boundaries. The bottom of the red zone has been 

 adopted as the upper limit of Mr. Medlicott's Nahan rocks in this part of 

 the Punjab. 



SlWALIK, 



Lower Siwalik, No. i5.— The "red zone ""^ alluded to is commonly 

 observable along the north side of the range, and on both sides of 

 the Bakrala ridge, but to the west it is difRcult to trace this red zone 

 among the disturbed rocks at the Indus near Mari and Ainwa. The red 

 band is succeeded by grey sandstones here and there, containing strings 

 of lignite, alternating first with red, and higher up with warm orange 

 clays, and some layers of conglomerate, in which mammalian bones, &c., 

 occur. The pebbles in these conglomerates are usually of hard quartzose 

 sandstone, but sometimes of limestone, and rarely of syenitic rocks ; 

 among them, pieces of purple or grey sandstone similar to those form- 

 ino" the harder varieties of the tertiary rocks are occasionally met with. 



One of these conglomerate beds among the nearly vertical sand- 

 stones south of Mount Tilla between the villages Bidar and Hun was 

 searched for evidence of later tertiary denudation of the Mount Tilla 

 series, but the only recognisable detritus belonging to that series con- 

 tained in this conglomerate were numerous pebbles of limestone enclosing 

 ( 110 ) 



