GNEISSIC EOCKS : TRAP DYKES. 61 



to the northward, wliicli runs parallel with it for many miles. Just 

 before the parallel dykes cross the Karra Gudda, a bold and very pre- 

 cipitous mass of naked black rock some 80 to 100 feet hig-h, they are 

 joined by the great Karra Maldi (Curra Muldy) dyke, and between 

 them cover so large an area with huge blocks of black basaltic diorite 

 that it would be very easy on cursory inspection to imagine one was 

 dealing with a ti-ap-flow instead of only a meeting of dykes. The 

 parallel dykes are lost under a great cotton soil spread in the valley 

 •west of the Karra Gudda, and when they re-appear have trended to a 

 west-by-north course, which they keep for a while, but continue trending 

 till they reach a west-north-west course, which they continue till 

 lost to sight a mile on to north-west of the Hanam Sagur head-land. 

 The whole course of this set of dykes measures fifty-one miles, of which 

 twenty-four miles are double and a few miles triple. Numerous dykes 

 join, and several important dykes cross the set, but without showing any 

 indications of belonging to different periods. The main line of this series 

 passes near none but small villages. Jumalapur, which it is called 

 after, is the most important and close to the central triple part. 



One more occurrence of dioritic trap deserves mention ; it is that of 



a band of such width that it can hardly be 



lutrusive mass at As- ■, ■, j-i i, «, • ^ -i • 



j^j^|.^; reckoned a dyke, but unfortunately it is so com- 



pletely surrounded by a vast unbroken spread 

 of cotton soil that its relation to the gneissic rocks could not be made 

 out. This doubtful trappean intrusion occurs at the village of Asmatti, 

 five miles w^est-north-west of Nargund, and forms a long low rocky hill 

 on which the village stands. To the north and south the ridge dies away 

 rapidly under the cotton soil, but groups of large masses protrude at 

 intervals, showing that it extends in a north-by- west to south-by-east direc- 

 tion for about three miles, with a width of two-thirds to three-quarters 

 of a mile, — a width greatly exceeding the very largest of the ordinary 

 dykes met with elsewhere in the Peninsula, the width of which was 

 not more than 400 yards. For this reason, and from a slight difference 



( 61 ) 



