B WAAGEN WYNNE: GEOLOGY OF MOUNT sfftBAN. 



trast to the slate hills of softer and more monotonous outline, which rise 

 immediately from its north-western slope. It has an elevation of 6,243 

 feet, with an elongated oval base, is entirely isolated from the surround- 

 ing hills by deep narrow glens, and is penetrated by steep sided ravines 

 radiating from the summit. Its form is massive, and its outline heavy, 

 presenting convex curves to the northward, suddenly interrupted by 

 precipices, which, facing to the southward, extend along its crest and 

 send rugged broken spurs into the valley below. 



The structure of the mountain is interesting, affording, as it does, 

 an epitome of much of the geology of the North-West Frontier of 

 British India, there being, indeed, not many members of the series, as 

 at present known, absent, and those unrepresented being chiefly the 

 oldest crystalline arid the newer divisions of the tertiary rocks. 



Different portions of the ground afford sections differing not only 

 in their comprehensiveness, but also in there being strata present ia some 

 which do not recognisably recur in others. A great longitudinal fault 

 traverses the whole mountain, besides smaller dislocations in other direc- ' 

 tions, while one prominent unconformity, another less perfectly apparent, 

 and possibly yet others latent, go far to explain the want of uniformity 

 in the sections from which the following succession has been deduced : — 



6 NuMMULiTic ... Thick limestones with some shales — fossils in places. 



^Thin-bedded limestones — without fossils apparently. 

 5. — Ceetaceous — ) Impure ferruginous sandy limestone, weathering rusty — 



(. fossils. 

 4.— JUEASSIC ... ... Black Spiti shales. 



UnconformUi/. 



(^Thin-hedded limestone and slaty shales. 

 3' — Teiassic ... — (Dolomite, limestone; fossiliferous {Megalodon and other) 



(. beds. 

 2, — Below the Teias ... Hsematite, dolomite, quartzite, sandstone and breccia. 



Unconformity. 

 1.— Semi-oeystalline ... Attock (?) slate. 



The whole character of the divisions just mentioned admits of no 

 doubt that the strata exposed at Sirban possess the Alpine facies well 

 ( 332 ) 



