GEOLOGY OP THE TJPPEK PtJNJAB. 375 



that the elevation was earliest or greatest in the region where the 

 Indus, the Satlej, and the Brahmapootra rivers rise among the 

 central portions of the Himalaya Mountains. 



That glacial conditions prevailed in the Western Himalaya during 

 the post-Tertiary period, either to a greater extent or nearer to the 

 Rawal-Pindi plateau than they do at present, is to be inferred from 

 the distribution of the large erratic blocks noticed, their transport to 

 where they now rest being attributable to flotation by ice, for want 

 of other evidences of glacial action such as moraines or glacial 

 striaa, to the preservation of which, however, the climatic conditions 

 are not favourable. 



It would also appear that another and an older glacial period 

 may have affected part of the formerly existing land to the south- 

 ward ; this is shown by the striated boulder of a red granite, 

 unknown in the Himalaya, found by Mr. Theobald on the Salt 

 Range, and fairly presumable to have been enclosed among the pre- 

 Tertiary (or Cretaceous ?) Boulder-clay of that country. Should its 

 striation have occurred since it was removed from this boulder-bed, 

 the glacial period would have been later, probably post-Tertiary, and 

 would account both for the presence of such blocks as the one near 

 Khewra, and for the distribution of the numerous small boulders of 

 the same granite in the country near the east end of the Salt Range. 

 It must be remembered, however, that the clay and boulder-bed 

 whence this block is supposed to have come answers very closely to 

 the description given of the ice-scratched boulder-bed of the Talchir* 

 group described by Mr. Feddenf . 



In connexion with the subject of this Cretaceous (?) boulder-bed 

 it may be mentioned that such boulder-shales or clays, first found 

 in the Talchir rocks of central peninsular India by Mr. W. T. Blan- 

 fordj, are now known to occur in other places as well. He has 

 recently described an earthy boulder-bed near Lowo and Pokran, in 

 the Sind desert §, older than the Jurassic beds of that country, older 

 even than rocks supposed to be of Yindhyan, and consequently of 

 Palasozoic age. These occur under circumstances which render it 

 possible that they have been transported by ice ; so that it appears 

 there are different horizons, sometimes widely apart, in the Indian 

 geological series upon which ice-borne ciystalline blocks are found, 

 usually enclosed in soft earthy deposits. Hence the very oldest of 

 the Salt-Eange Boulder-clays resting upon the salt-marl may yet be 

 found to contain ice-scored blocks, and all may indicate a recurrence 

 of glacial periods in India, dating from very early geological ages. 



EXPLANATION OF PLATE XIV. 



Sketch Map of the Geology of the Upper Punjab. (Scale 50 miles to an inch.) 



* Talckeer. Trias according to Dr. Feistniantel. 

 t Eecords Geol. Surv. Ind. rol. viii. p. 16. 

 I Memoirs Geol. Surv. Ind. vol. hi. p. 37. 

 § Eecords Geo], Surv. India, vol. x, p. 17» 



