204 NICOBAR ISLANDS AND ABORIGINES 



Nicobar, Teressa, Bompoka, Kamorta, Trinkat, and Nankauri) 

 and the sandstones and slates of the southern (Kachal, Little 

 and Great Nicobar) appear to be only petrologically different 

 products of one and the same period of deposition. There 

 are, at the same time, very few materials from which the age 

 of the marine formation could be determined, as the only fossil 

 remains which have been found in their strata are fragments 

 of driftwood changed to brown coal, plants resembling Fucoids, 

 Foraminifera, and PolycistincB. All these indicate more or less 

 distinctly a young Tertiary age. 



" We find a repetition of the geological condition of the 

 Nicobars on the southern coast of Java and the south-west 

 coast of Sumatra. 



" The third principal formation of the Nicobars are coral forma- 

 tions belonging to the most recent or the present period. Coral 

 banks of great thickness are found on Kar Nicobar, Bompoka, 

 Trinkat, and other islands. They consist partly of compact coral 

 limestone, partly of a coral and shell conglomerate upheaved 

 30 or 40 feet above the present level of the sea. On all the islands 

 the original area is to be observed enlarged by coral land which 

 is only separated by the higher sand-dunes along the shores from 

 the still continuing formation of the coral reefs surrounding all 

 the islands in the character of fringing reefs. Although these 

 raised coral banks are decided evidence of the long-continued 

 upheaval of the islands — that, in connection with the eruption of 

 the serpentines and gabbros — the formation of the flat coral lands 

 elevated a few feet only above the sea, can, on the other hand, be 

 explained by the accumulation of coral fragments, of sand and 

 shells, by the waves and breakers on the shallow surface of the 

 fringing reefs." * 



Coal of a brown variety has been found in Little Nicobar, 

 Treis, Milo, and Kondul, but everywhere in isolated masses and 

 single fragments, showing traces of rolling, met with here and 

 there without order, in sandstone and slate, and evidently derived 

 from driftwood. 



The only traces of minerals discovered have been ores of 



* Vide paper on the "Geology of the Nicobars," by F. von Hochstetter, 

 translated by Dr Stoliczka, Proc. Geol. Survey, India. 



