G2 W. BLANFORD, WESTERN INDIA. [PaRT I. 



pebbles occur high up in the latter, especially in the neighbourhood of 



Ruttunpoor; from some of these are derived the agates used by the 



Cambay lapidaries. 



There is, however, evidence that the denudation of the traps had 



been considerable even before the commencement of 

 Denudation of traps • -, /> ^ ■ ■ n •, • ii t- 



prior to deposition of the period of deposition of the tertiary beds. It is 



tertiary beds. -i-rr> ^ • ^ i t -i 



generally very difficult to ascertain the exact strike 

 of the traps, but about 4 miles south-east of Turkesur, at a village called 

 Ooskur, a very peculiar bed is found interstrati- 

 fied with the lava flows ; it has somewhat the ap- 

 pearance of a hardened shale, but still more that of a fine volcanic ash 

 arranged by water. It is somewhat disturbed, but easily traceable, and 

 it strikes at about west 40° south. The dip is not distinct, but is in 

 places high. The boundary of the nummulitic beds resting upon the 

 trap strikes about south 5° west, and their dip does not exceed 5°; the 

 two L'nes gradually converge until the tertiary beds completely overlap 

 the band of shaley ash. 



There can be no reasonable doubt but that this ash (?) bed is 

 interstratified with the traps. It has in no way the appearance of a 

 dyke or vein, but rather of sedimentary rock. The nummulitics must, 

 therefore, rest on the denuded edges of the traps. 



There is also considerable appearance of unconformity near Sursho 

 hill, east of Ruttunpoor. At the hill itself there 

 is so much disturbance that it is impossible to 

 say what are the relations of the nummulitics to the traps, but east 

 of the hill and south of it, — not, it is true, quite close to the nummuli- 

 tic boundary, but still not more than a mile or two from it, — the traps 

 have a distinct southward dip, and this is a continuation of a similar 

 dip traceable to the eastward for at least 50 miles. Now, upon these 

 traps, thus dipping south at angles averaging about 10°, rest tertiary beds 

 dipping west and north-north-west at various angles, averaging perhaps 

 ( 224 ) 



