TERTIARY AND RECENT DEPOSITS. 2')7 



Large gravel beds of the age of the younger alluvia are not often 

 met with. One of the best examples of such a gravel bed is that form- 

 ing the left bank of the Tungabhadra at Chikkalbarri^ six miles south of 

 Bhima in the Raichur Doab. The gravel is typical of the Tungabhadra 

 river, containing, besides quartz, quartzite, and gneissic pebbles, a large 

 number of banded red and grey jasper pebbles mixed with sand. The 

 gravel extends fully a mile inland from the river^ but is then hidden by 

 cotton soil. 



A dark reddish-brown clay occurs frequently in the banks of the 



Don river, which drains the great plain south of 

 Clay. 



Bijapur. This red clay graduates upward into 



the black regur-like alluvium. Similar clay is not uncommonly seen in 



many of the other rivers. 



A considerable development of rich brown loam was observed by 



Mr. King in the valley of the Bhima near 

 Loam. 



Ferozabad. 



In several places deposits of gravel and coarse shingle occur, the 

 High level or older position of which cannot be satisfactorily accounted 

 ^"^^^^ ^' for by attributing them even to very exceptionally 



high floods of the existing rivers. They occur on the banks of the 

 Krishna, Bhima and Tungabhadra rivers and some of their tributaries, 

 at elevations from 60 to 80 feet above the ordinary flood levels. 



There can be little doubt that these rivers were affected by causes 

 not now in action, by which their waters were raised to heights vastly 

 exceeding the very highest flood levels now attained. The causes which 

 thus affected the rivers were probably the existence of several barriers 

 along their courses, by which their waters were dammed back to great 

 heights above their present level. Such barriers doubtless crossed, in 

 former times, the valleys of the Krishna, Ghatprabha and Malprabha 

 rivers at the several places where they have cut through the several hill 



( 237 ) 



