134 
Records of the Geological Survey of India. 
[vol. VII. 
drain into the Toongabadra. On the south side of this valley the hills widen out consider¬ 
ably owing to the presence of a third ridge, but contract again to the south of the 
Kappatgode. 
The ridge in its northern part, lying beyond the gold tract (where it is single and its 
„ , structure quite simple) shows a double series of hsematite 
Geological structure of the ridge. , , i . ,, 
schist beds intercalated between chlontic and other 
schists of great thickness, which to the east touches a broad band of highly silicious and 
often granitoid gneiss, on which stands the town of Gudduck. I found no section showing 
the exact relations of these two series; but it is most probable that the granitoid series, which 
may conveniently be called the Gudduck series, overlies the chloritic and ferruginous beds. 
On reference to the map accompanying these notes, it will be seen that further south a third 
hematite schist band appears at a still lower level, also accompanied by chloritic, hornblendic, 
and micaceous schists, and bends round on itself in a sharp curve immediately north of the 
Kappatgode, thus forming an anticlinal ellipsoid, which is crossed by the road running from 
Dambal to Soortoor. To this series I will give the name of the Dhoni series, from the 
village of Dhoni, which stands on it. This series is noteworthy, because containing several 
important beds of grey and greenish-grey crystalline limestone of considerable thickness, which 
would yield a building stone of great beauty and excellence, and far cheaper to work than any 
of the granitic rocks of the neighbourhood. If pure enough to yield good lime on burning, 
it would prove of great value in the event of the railway extension between Bellary 
and Hoobly being carried out, through a country otherwise poor in limestones. The 
principal beds lie in two groups, the one 2 miles north-west of Dhoni, the other 3 miles 
west-south-west of that village. Overlying this to the westward are other hocmatitie beds, 
the representatives doubtless of those before named, if not, indeed, the extensions of the 
same. As these beds form the mass of Kappatgode Hill, 1 will call them, and their more 
northern representatives, the Kappatgode series. The character of the associated schistose 
beds has changed, however, from chloritic to argillaceous, and the predominant color of the 
rocks from green to reddish buff or mottled whitish. Owing to the great development 
of cleavage, the true dip of these argillaceous schists is in many places perfectly obscured, 
and their relation to the rocks next following them to the westward very problematical. 
This next series consists of chloritic and hornblendic schists, intimately associated with 
a massive dioritic rock. This dioritic rock, though in parts strongly resembling some 
of the diorites forming the trap-dykes, which occur so frequently in the gneissic region, 
does not appear to be an irruptive rock, but rather a product of excessive metamorphism. 
The schistose rock appears to pass by imperceptible graduation into the highly crystal¬ 
line mass. Nowhere did I find the two dissimilar rocks in close apposition, but every¬ 
where some feet or yards in thickness of rock intervened, showing the graduation of the 
special characters. This series, which I will call the Soortoor series, after the large village of 
that name, at which the principal gold washing is carried out, occupies a band of country 
some 4 to 5 miles broad, which is bounded to the westward by a band of granitoid gneiss of 
undetermined breadth. The position of this granitoid band (which may be called the 
Moolgoond series) relatively to the Soortoor series is uncertain; but it is probable that the 
latter series is the younger of the two. 
All the streams said by the natives to be auriferous rise within the limits of the tract 
occupied by the Soortoor series; and the upper course of the Soortoor nullah, the richest of all, 
lies entirely within the area occupied by the pseudo-diorite, and associated chloritic schists. 
Quartz reefs occur in all the rock series above enumerated, but those lying within the 
limits of the Soortoor series are tho best defined, and, with 
Quartz reefs in the Soortoor series. „ , ,, , 
a few exceptions, have the most promising lie, their direction 
being mostly north-by-west, south-by-east, or parallel to the strike of the bedding. The 
surface of the principal reefs has been much broken up, doubtlessly by gold-seekers. 
