GO FOOTE ! GEOLOGICAL STRUCTURE OF THE EASTERN COAST. 



deous texture, the reddish yellow mass being- largely permeated by minute 

 silicious veinlets and threads of lighter colour. No organic remains could 

 be traced in this strange bed, nor could its relations with the typical 

 plant beds near-by be seen, owing to the great development of cotton 

 soil around it. All that can be said of it is that it lay unconformably 

 on the gneiss. When I first visited it in May 1875, it was being 

 largely worked as revetment material for sundry tanks and wells ; and 

 by December of the same year I found that but very little remained to 

 be carried away. 



A spread of alluvium, of 7 miles in width, lies between the 



TheVemdvaramSuda- southernmost point of the Yendlur patch of the 



vada group Sections on Ongole group of plant beds and the nearest ex- 



the banks of the Gundla- & . 



kamma. posure of equivalent rocks belonging to the 



Vemavaram group which occurs on the north side of the Gundlakamma 



river at Gazulapadu, about a mile north-east of the travellers' bungalow 



at Velampalle (Valumpully) . 



The Gazulapadu section, which can only be seen when the river is 

 quite low, shows very sandy kankarry clay, underlaid by orange and 

 brown rather friable sandstone and grits, pebbly grits, and coarse conglo- 

 merate, all apparently part of one large variable bed. The conglomerate 

 contains fragments of an old laterite ; and a number of boulders of an 

 identical rock are seen in one place resting on the clay bed just mentioned. 

 The boulders are from 18 to 20 inches in diameter, and are themselves 

 surrounded by the overlying alluvium, which here forms a considerable 

 cliff. 



The sandstones and grit bed can be traced all along the base of the 



alluvial cliffs from Gazulapadu to Kirtipadu (Keerteepaudoo) , where it is 



hidden by a sandbank ; but it re-appears again in the next reach of the 



river in the northern bank, and can be followed till nearly opposite 



Nandipadu (Nundeepaudoo) , when it disappears. 

 Vemavaram patch. 



Grey or brown sandy shales — true plant shales — ■ 

 are shown, by means of well-sections both east and west of Nidamanur, 

 to occur below the thick cotton soil which there forms the surface. They 

 ( 60 ) 



