ATTOCK SLATES. 3 



developed in the formations of tlie great north-western Himalayan 

 region. It is^ therefore^ in this direction that we should seek for a 

 correlation of the Sirban strata with the latter, but unfortunately the 

 most detailed information relating to this Himalayan region is that 

 regarding the Spiti district, which is separated from Hazara by the 

 whole of Cashmere, with all its accumulations of crystalline and 

 eruptive rocks. Besides, Spiti lies on the north-eastern side and Hazara 

 to the south-west of the lofty crystalline range, continuing from the 

 Pir Punjal through the Kyjnag, in Cashmere, towards the north-west. 



Notwithstanding the distance and diilerenee in orographical posi- 

 tion, the aifinity between the Hazara and Spiti rocks is in certain points 

 even greater than one would have expected, and Dr. Stoliczka's Memoirs 

 on Spiti and Western Tibet* in many respects afford guidance in study- 

 ing the formations of the Hazara mountains. 



1. Attock Slates. — These are apparently the upper portion of 

 " the slate series, which is in other places metamorphosed into talcose schists, 

 and presents a complex transition into the porphyritic syenite of the 

 mountains to the northward, at a distance of fifteen or sixteen miles 

 from Sirban. The series varies greatly ; is, so far as hitherto searched, 

 quite unfossiliferous, and is most accessible at Attock on the Grand 

 Trunk Road. At Attock, and in other places, it includes massive zones 

 of limestone, generally of dark colour, but sometimes white and flaggy, 

 and in texture either resembling lithographic limestone, or horny, or 

 finely saccharine, as if metamorphosed. 



At Sirban the slates are usually dark or black, alternated with 

 greenish-gray or olive sandstones, and have sometimes a deep liver 

 colour. Some limestones associated with them in an outlying hill near 

 Dhumtour may belong to such zones as abovementioned. The cleavage 



* Memoirs, Geological Survey of India, Vol. V, p. 1 : ibid, Vol. V, p. 337. 



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