TOPOGBAPHY. 25 



elevations and in ascending order the forest of ban] oak (Q. 

 incana) and blue pine (P. excelsa), of miru oak (Q. Dilatata), of 

 deodar (0. deodar a) and Jcharsu oak (Q. semicar pifolia) , of spruce 

 (P. morinda'j and silver fir (A. Webbiana). 



2. The Submontane Siwaliks. The great boundary fault of 

 the Himalayas runs from end to end of the submontane areas of 

 the province (i.e., between Nepal and Punjab frontiers), and 

 absolutely limits the distribution of the Precambrain Himalayan 

 rocks and the Tertiary Siwaliks ; this often inconspicuous fault 

 sometimes running along some small and insignificant ravine 

 forms a stratigraphical break of almost inconceivable duration. 

 This great fault, except for one or two areas, e.g., Lansdowne 

 division, for all practical purposes forms a clear cut northern 

 boundary of the distribution of the sal, the occasional patches of 

 scrub sal found on the older Himalayan rocks being of no account 

 whatever. 



Middlemiss 7 has classified the Tertiary Siwalik formations into 

 the following zones : 



(a) Upper Siwalik conglomerate, 

 (6) Middle Siwalik sandrock, 

 (c) Lower Siwalik sandstone. 



Of these (a) and (6) are normally strictly conformable, but are 

 usually sharply separated from (c) by reversed faulting. 



The sandrock consists of soft friable sands and occasional clay 

 beds becoming coarser, with' small pebbles in the upper layers, 

 and merging gradually into the boulder beds and gravels of the 

 conglomerates. These conglomerates, once loose river shingle 

 beds, have become so indurated with lime that they have become 

 hard, and usually form a very distinctive escarpmen-t (e.g., the 

 Akhiri Danda of Eamnagar and the outer ridge of the Siwaliks 

 at Dehra), and sometimes present a curious scenic effect of great 

 needle-like pinnacles towering up precipitously for 100 feet or 

 more. These two formations were once old Bhabar areas, deposited 



7 Memoin of Me Geological Surety. 



