22 THAI'S AND INTERTRAPPEAN BEDS 



were not published before 1862, when Dr. Carter'^ made them known. 

 He had previously mentioned the occurrence of nummulites in the 

 Rajpipla hills in his '' Summary of the Geology of India.^' These 

 beds containing- nummulites have been carefully examined by the 

 survey and found to extend along the edge of the traps from near Surat 

 to the neighbourhood of Broach. The fossils collected from the lowest 

 beds have been partly determined by Dr. Stoliczka, and are unmis- 

 takably lower eocene (Parisien) . 



Thus lower eocene and middle cretaceous beds were known to exist 

 in immediate connexion with the traps, but nothing whatever had been 

 ascertained of their relations to the volcanic rocks. One of the most 

 interesting geological questions in "Western India was to ascertain these 

 relations. 



This has now been done with the following results. The lower 

 eocene beds of Surat rest quite unconformably upon the traps, and 

 there is clear evidence of an enormous amount of denudation of the 

 latter, both before and during the deposition of the nummulitie beds. 

 Not only do the eocene rocks rest upon the denuded edges of the 

 traps, but materials derived from the latter enter largely into their 

 composition, a thick conglomerate of rounded trap pebbles forming 

 the base of the nummulities in many places, and hundreds, perhaps 

 thousands, of feet of gravels occurring in them, the pebbles of which are 

 chiefly agates derived from the trappean rocks. f There can thus be no 

 question that the lower eocene beds are much newer than the volcanic 

 series of Malwa and the Deccan. 



There is also unconformity between the traps and the middle 

 cretaceous beds of Bagh, and this unconforinity is, in places, very 



* Jour. Bombay, Br. Roy. As. Soc, Vol. VI, p. 164. 



t Some of these beds of pebbles west of Broach furnish the agates, carnelians, ic, 

 which are worked by the lapidaries of Gambay. 



'( 158 .) 



