SOILS AND SUB-AERIAL DEPOSITS. 



99 



together loose materials of all ages and descriptions, forming conglomerates 



and breccias of all characters, is the next in importance, and probably also 



in point of quantity. Lastly come the massive tufas usually forming 



superficial deposits, which are occasionally of some little importance. 



These appear to be in many, if not in all, cases to be really only 



a fuller consolidation, or a completion of the process to the partial 



action of which the other two forms of tufa are due. Examples of 



this are also very common, but a few of the more striking examples 



Massive kankar near deserve to have attention drawn to them. An 



extensive pavement-like spread of massive tufa 



occurs a couple of miles west-by-north of Pamur, under the bund 



of the Dupuguntla (Doopoogoontla) irrigation tank. Several small 



springs issue from below this mass, which rests upon gneiss. Another 



remarkable and extensive spread of tufa occurs at 

 At Kanigiri. 



the Kalingula (waste weir) of the large tank at 



Kanigiri, and extends for a considerable distance westward under the 



red soil. 



Another great pavement of kankar is to be seen at the north-eastern 



end of the Kotappa Konda, and another of the same 

 Near Kotappa Konda. 



character at Yallamanda, a mile or so to the north- 

 east and 4 miles south of Narasaraopett. The surface of the tufa here 

 shows a remarkable coralloid sculpturing unconnected with any internal 

 structure, but due apparently to the action of rain. 



There is a great development of hard sub-crystalline kankar tufa 



north of Naganla, and about 34 miles north of 

 AtNaganla. . . 



Budavada. Here the junction of the gneiss and 



overlying Rajmahal beds is completely concealed by the thick bed of 



very large quasi-stalacmitic masses. 



The last example of massive tufa is perhaps the most remarkable 



of all. It occurs along the brow of the high ground south of the Pal- 



eru valley, 3 miles northward of Kandukur. It is best seen at Konda- 



kandukur, where it forms sheets as it were in the bed of the large 



tank, 



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