INTRODUCTORY. 13 



and there is no reason to suppose that any part of it^ except what forms 

 the floor of the Konkan, has been at any time depressed helow the sea- 

 level. The surface is everywhere uneven^ and no approach to a marine 

 plain of denudation was seen. A certain apparent levelness in parts of 

 the country is due really to the nearly horizontal position of the trap- 

 flowSj and to their general homogeneity of texture over large areas. 



The rate of denudation of the trap rocks is a very high one, and 

 apparently greater in the dry, hot climate of the Deccan, than in the 

 moist and cool climate in the mountain region. 



The second question — whether any inferences can be drawn as to 

 the character of the agencies which shaped the older land surfaces — 

 admits of much less satisfactory answer, because of the comparatively 

 very small amount of evidence remaining. Of the surface on which 

 the Deccan trap-flows were poured out, there is every reason to conclude 

 that it was a true land-surface, occupied probably here and there by 

 small lakes, the traces of which remain in certain small sub-trappean 

 deposits of gravel, sandstones, marls and clays of limited extent, which 

 will be found described further on. The shape of that land-surface as 

 it then stood was unquestionably of sub-aerial formation ; but whether 

 the rather level character of the general surface of the series of azoic 

 sedimentary rocks on which the trap flows chiefly rest may not have 

 been a remaining feature of a previous marine plain, is an open question. 

 In the Konkan region, Mr. Wilkinson^s very interesting section, above 

 referred to, seems to show that there the Deccan trap had certainly been 

 poured out over a true plain of marine denudation. 



The character of the surface of the gneissic rocks on which the 

 last-named azoic rocks were deposited was eminently that of a marine 

 plain of denudation. It was of very wide extent and showed but very 

 few inequalities, and those only of the very hardest and most unyielding 

 rocks. 



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