3 J- WYNNE : TRANS-INDUS SALT REGION, KOHAT DISTRICT. 



of the Salt |Range, and on the evidence of some shelly limestone layers 

 containing' minute unrecognisable fragments, near Bahadur Khel, at the 

 base of the nummulitic group, has apparently considered the Jurassic 

 formation to be present, and has introduced a colour to represent it on 

 his map at that place, (paper already quoted, Jour. As. Soc, Beng., 

 1867, p. 26). 



A careful search for Jurassic beds at the locality only resulted in the 

 discovery of some thin limestone full of broken shells, apparently of 

 oysters, which may be those Dr. Verchere mentions. Such beds are not 

 uncommon in other parts of the district among the inferior layers of the 

 nummulitic limestone and underlaid by other lower beds of that forma- 

 tion containing Nwmmulites, &c, sometimes in abundance. Hence the 

 introduction of an older formation than the nummulitic, on what may 

 have been no better grounds than mistaken identity, has been avoided. 



Failing the discovery of any clue leading to a more satisfactory 

 conclusion, we are forced to draw upon probability in the effort to assign 

 a place geologically to this Trans-Indus salt series. 



To follow the vague indications of early writers, and assume that 

 this salt series is an extension of that of the Salt Range, involves the 

 acceptation as facts, that the salt and gypsum here are not more recent 

 than silurian ; and that in the Salt Range region now at a distance from 

 this of say thirty"* to ninety miles, (while the salt series was being 

 gradually covered up by seven different thick palaeozoic, mesozoic, and 

 cainozoic formations) conditions bere underwent little change, and noth- 

 ing was deposited after the main body of the gypsum to mark the lapse 

 of so many great geological eras except a comparatively thin accumula- 

 tion of ferruginous mud ! 



It might be said that the Upper Punjab formations are all excessively 

 subject to lateral change, and that scarcely one formation or group is 



* At one place north of Kalabagh the salt of the Loon (Ltin) nallah belonging to the 

 Salt Range series is found within about eighteen miles of that belonging to this district at 

 Nundrukki. 



( 138 ) 



