GEOLOGY. 
15 
PART II. 
The hill ranges between the Indus Valley in Ladak and Shah-i-dula on the 
ERONTIER OE YARKAND TERRITORY. 
[ This section is copied, with a few verbal alterations, from the Records of the Geological Survey of India, Y°l. VII, p. 12.] 
The following brief notes on the general geological structure of the hill ranges alluded 
to are based upon observations made on a tour from Leh, via Changchenmo, the high plains 
of Lingzi-thung, Karatagh, Aktagh to Shah-i-dula, and upon corresponding observations 
made by Dr. H. W. Bellew, accompanying His Excellency Mr. Eorsyth’s camp along the 
Karakoram route to this place. 
Before proceeding with my account, I will only notice that our journey from Leh (or 
Ladak) was undertaken during the second half of September and in October, and that we 
found the greater portion of the country north of the Changchenmo valley covered with 
snow—the greatest obstacle a geologist can meet on his survey. While on our journey the 
thermometer very rarely rose during the day above the freezing point, and hammer operations 
were not easily carried out. At night the thermometer sank, as a rule, to zero, or even to 8° 
below zero, in our tents, and to 26° below zero in the open air. Adding to this the natural 
difficulties of the ground we had to pass through, it was occasionally not an easy matter to 
keep the health up to the required standard of working power. 
Near Leh, and for a few miles east and west of it, the Indus flows on the boundary 
between crystalline rocks on the north and eocene rocks on the south. The latter consist 
chiefly of grey and reddish sandstones and shales, and more or less coarse conglomerates, 
containing an occasional Nummulite and casts of Pelecypoda. These tertiary rocks extend 
from eastward south of the Pankong lake, following the Indus either along one or both 
banks of the river, as far west as Kargil, where they terminate with a kind of brackish and 
fresh-water deposit, containing Melania. 
Nearly the entire ridge north of the Indus, separating this river from the Shay ok, and 
continuing in a south-easterly direction to the mouth of the Hanle river (and crossing here 
the Indus, extending to my knowledge as far as Eemchok), consists of syenitic gneiss, an 
extremely variable rock as regards its mineralogical composition. The typical rock is a 
moderately fine-grained syenite, crossed by veins which are somewhat richer in hornblende, 
while other portions contain a, large quantity of schorl. Both about Leh and further 
eastward extensive beds of dark, almost black, fine-grained syenite occur in the other rock. 
The felspar often almost entirely disappears from this fine-grained variety, and quartz remains 
very sparingly disseminated, so that gradually the rock passes into a hornblendic schist; and 
when schorl replaces hornblende, the same rock changes into layers which are almost entirely 
composed of needles of schorl. Again, the syenite loses in places all its hornblende, the 
crystals of felspar increase in size, biotite (or sometimes chlorite) becomes more or less abund¬ 
ant, and with the addition of quartz we have before us a typical gneiss (or protogine gneiss), 
without being able to draw a boundary between it and typical syenite. However, the gneissic 
portions, many of which appear to be regularly bedded, are decidedly subordinate to the 
