Records of the Geological Survey of India. 
[vol. x. 
216 
V.— Shankan and Hath Ridq-es. 
In Section II we got as far as Kotkhai. I will make this our new point of departure. 
The road from Kotkhai (elevation 5,790 feet) passes over the Shankan ridge* at an elevation of 
9,500 feet, and then drops down to Deora (elevation 0,600 feet), the capital of the Jubal state. 
The dip at first north-east changed to oast-north-east, and then back again to north-east. The 
angle of dip, generally low, became flat at Deora. About a mile on the Kotkhai side of the 
Shankan ridge, a thin bed of “central” gneiss appears. Between it and Kotkhai, mica- 
schists, and occasionally silicions schists, prevail. I found it impossible to say where the 
Krol (Boileaugunj) schists and the Infra-Krol rocks ended and the crystalline series began. 
As far as outward visible signs went, there seemed no break in the conformity of the two 
series. On the crest of the ridge, I found a very thin bed of slate with a dark streak which 
seemed carbonaceous. I have observed this feature in other places well within the area of 
the crystalline rocks. These outcrops always seemed very thin, lenticular and local. Down 
to near Deora, the rocks are fine-grained mica-schists. One bed above the gneiss seems to 
retain its character all over the crystalline area. It is a fine-grained mica-schist that splits 
readily into large slabs, and is much used for roofing purposes. One slab I measured—and 
I give it as a fair sample—was one inch thick by 5 feet 8 inches long and 4 feet 2 inches 
wide. Viewed edge-ways, quartz seems to predominate, whilst the flat splitting face presents 
an unbroken surface of mica. On the descent there is a strong dyke of trap, the exact coun¬ 
terpart of the trap near Banellah on the flank of the Chor. As Deora is neared we come on 
the central gneiss, which is here a bed about 50 or 60 feet thick. It runs right round the 
head of the Deora valley, as indicated on my map. 
The principal characteristic of the “ central” gneiss is that it is always more or less 
porphyritic. In its lowest form the crystals are small and lenticular. As the metamor¬ 
phism advances, they become large and eye-shaped: in the next stage, they take the form 
of blunted cubes. The next advance is to assume a perfectly rectangular form. These 
crystals are usually about 1 j inches long, but sometimes (as in the Chor), they attain a length 
of nearly 3 inches. As the metamorphism advances, the axes of the crystals begin to point 
at an angle to the plane of foliation, and the angle gradually increases up to a right angle. 
Finally, they point in all directions, and all trace, or nearly all trace, of foliation is lost. 
When the rock arrives at this stage, all signs of bedding disappear, and the gneiss weathers 
out into large rounded masses after the fashion of true granite, and becomes very dense and 
hard to break. The porphyritic felspar crystals appear to be orthoelase ; twin crystals are 
not uncommon. An intensely black mica is another characteristic of this rock. It is a 
variety, I think, of Biotite. It takes no notice of concentrated sulphuric acid (cold), but 
continued boiling in this acid extracts all the iron of which the colouring matter consists. 
The rock also contains a silvery mica which is usually quite subordiuate to the other. 
We will now leave Deora for the present and return to Kotkhai. Our route thence will 
be up to Deori, the capital of the little state of Kanati. From Kotkhai to Deori the dip is 
east-lK-north, then north-east, then east-ll°-north again, in mica-schists and silicious 
schists. On one occasion I went by a direct mountain patli from Deori to Deora. I struck 
the “ central" gneiss above, and to tlie east of Deori, and again just above Deora. The bed 
passes under the mountains from the one point to the other. The outcrop in the Kanati 
(Deori) valley takes the form of cliffs, and can be followed by the eye right round the head 
of the valley. My last trip in this direction was up to the head of the valley, and along 
the ridge which crowns the valley, to Bagi and on to Narkanda. I struck the gueiss just 
above Thanari (Tharan, I presume, of the map), at an elevation of 8,300 feet, where it is seen 
extending for miles on either side in the form of clifl’s. The outcrop is here about 100 feet 
Shakondhar of the map. The road from Kot to Deora is marked oc the map. 
