20 GRIESBACH I RAMKOLA AND TATAPANI COAL-FIELDS. 



and there^ thick layers of red iron ore are intercalated between the 



Mahadevas ; and a few earthy beds are met with, the only beds which 



have yielded fossils. 



The total thickness probably does not exceed 800 feet, this being- the 



Thickness of the Ma- difference of height between the top of the Tamor 



* escarpnaent and the level below, which is composed 



of older rocks. 



The rock masses of the Mahadevas are traversed in all directions by 



joints ; the steep outlines of the escarpments no 

 Jointing. 



doubt owe their existence to this extensive joint- 



i ng. As masses of the rock are undermined by the rivers below, blocks, 



more or less approaching a cubical shape, separate from the cliff above 



and come down the hill sides, thus always preserving a freshly broken 



surface to the escarpment, as shown in fig. 1, where, owing to the 





j_ f,y 



Fig. 1. Mabadeva escarpment of the Tamor hill, valley of the Mahan river. 



inclination of the strata, the face of the cliff is actually overhanging, the 

 rocks splitting off along the joints, which are mostly normal to the line 

 of bedding. 



( 148 ) 



