TATA PAN I AND SENDUR RIVER SECTIONS 29 



It is very difficult to arrive at a true estimate of the thickness of the 



Talchir beds, owing to the rolling character of the 



Thickness of Talchirs. ,. , .. ,,,,,,,i ,• . n y i. 



dip ; but it IS probable that the estimate ot about 



700 feet for the Tatapaui sections comes very near the truth. 



The strike and dip of the Barak ars remain perfectly uniform in 



the Bithiau nullah; the former is north-south, 



Thickness of Barakars. „ i ,i , / t i • j ^ 



and dip is at 20 , to west, and the total horizontal 



length of the Barakar section being 2,640 feet, the thickness is exactly 

 900 feet. This is confirmed by the sections north of Tatapdni, in the 

 Chechra section and neighbouring nullahs, where I found a total hori- 

 zontal length of section of 4,336 feet with a dip of 12°, to west-20°-south, 

 which results in a total thickness of Barakars of 902 feet. 



The iron shales (17 to 18) which are intercalated between the Barakars 



and the following groups are very characteristic, 

 Iron shales. . n i tt i • 



and occur near the junction of the Bithiau nullah 



with the stream which rises near Moua-t. 



Though there is no break of conformity between this series of Bara- 

 kars and the following- beds, yet there is a sudden 



Eauiganj base-bed. 



and decided change of lithological character. On 

 the iron shales rest masses of clay iron ore of considerable thickness, 

 which being in situ in the river, have been denuded into the most 

 grotesque forms. Evidently lying on it conformably, are masses of thick- 

 bedded sandstone { 1 9j of ashy-grey colour with angular grits of quartz 

 and large leaves of mica. Carbonaceous markings and indistinct plant- 

 remains are found throughout the rock. It is very friable and crumbles 

 away. Inclosed in this mass of gritty sandstone are lenticular masses of 

 light grey micaceous shales, without fossils. Above it follows a pebble 

 conglomerate of similar general character. These sandstones I consider 

 as the base-bed of the Raniganj series, and it remains pretty constant 

 in all the Tatapani sections. 



( 157 ) 



