part 3.] Wynne: Tertiary zone and underlying roclcs in N.-W. Panjab. 125 
glacial action,* and the widely spread, well-stratified post-tertiary silt would indicate aqueous 
conditions in the vicinity, which might have facilitated the distribution of these erratic 
blocks. 
Supporting Rocks of the Tertiary Zone. 
I shall now endeavour to convey as briefly as possible some slight idea of the palaeozoic 
and mesozoie formations bordering the tertiary zone in this district. 
Southern or Salt-Range Rocks. 
The nine Salt Range groups of palaeozoic and mesozoie formations, included in the list 
(ante p. 113) exhibit parallelism and conformity throughout; this, however, may be only a local, 
yet marked, peculiarity. Another as great is that the strata composing the sections at either 
end of the range are strikingly dissimilar. One formation or group may be traced thinning 
away and becoming overlapped by another at various points along it, so that in no place is the 
full section obtainable. Besides this the whole region has undergone most violent disturbance, 
resulting in displacement and contortion, sometimes one or both being prominent, and in places, 
owing to this, tlio oldest and newest of the groups are brought into contact. The outcrop ou 
the scarped side of the range is thrown frequently into such intense confusion from land-slips 
caused by the deliquescent nature of the salt-marl that it is difficult to reproduce it on any 
map, and entirely impossible on the roughly reduced outline given with this paper. 
“ Saline Series.” —The red marl, gypsum, and rock-salt forming the lowest group is as 
mysterious in its origin as strange in its development and economically important, producing a 
large annual revenue of about £400,000 sterling. The salt occurs in the upper portion of a 
mass of red gypseous marl, and underlies massive, white, stratified gypsum. It shows a thick¬ 
ness of 600 feet at the Mayo mines, of which 225 are almost chemically pure salt (Dr. 
Warth’s paper, No. 11 of list). 
“ Purple Sandstone.’’ —Thick sandstones, earthy below and of deep purple colour, be. 
coming whitish at top, succeed the saline series. This “ purple group ” extends far to the west 
but there becomes thin, and the sandstones give place to dark earthy conglomerates contain¬ 
ing crystalline boulders of red granite and other rocks. It contains no fossils, so far as known. 
“ Obolus beds.” —In the next formation, however (also ranging widely westward), a belt 
of blackish clunchy shale, with sandy layers, was found to contain, at one or two places, the 
small detached valves of Obolus or Siphonotreta, a Silurian form, locally numerous, but 
entirely by themselves. 
“ Magnesian Sandstones.” —This group is to the east succeeded by, and connected with, a 
strong lightly coloured set of beds, the most conspicuous of which are hard, compact, magnesian 
layers, varying from dolomite to magnesian sandstone, and associated with flaggy and darker 
shaly bands, often covered with fucoidal and annelid markings. This formation has a more 
limited extension than the last, and was doubtfully thought by Dr. Waagen possibly to 
represent tbe carboniferous limestone of the west. Prom its position in certain sections, it 
appears to underlie that group, so I have preferred to keep it provisionally separate, 
particularly on account of its partial intercalation with the zone below, just where it is least 
recognisable to the westward. 
“Speckled Sandstone .”—The next group is a massive succession of speckled light- 
coloured or reddish sandstones, with purple clays and conglomerate bands, the pebbles of 
which are chiefly of old crystalline rocks. At the top of the group, pale lavender clays (said 
to contain small concretions of copper pyrites) are constantly present. 
* As pointed out by Mr. Croll would generally be tbe case (Climate ami Time). 
