NAMBOR FALLS SECTION. 87 



good continuous section of the shale-series is seen. The upper beds 

 are hard laminated grey shales, interbedded with grey micaceous 

 sandstone. These pass down into similar shales with occasional 

 sandy bands. The dip is always low but undulating. Below this the 

 sandstone dies out and frequent layers of lenticular, calcareous con- 

 cretions occur. These concretions are generally traversed by thin 

 veins of hard calcite, which stand out and give them the exact 

 appearance of a tortoise-shell. The lenticular nodules increase in 

 size, from about 1 foot in diameter and 2 or 3 inches in thickness, to 

 several yards in diameter and feet in thickness, and in fact, until the 

 neighbouring ones join together and form the hard, calcareous bands, 

 up to 2 and 3 feet thick, interbedded in the shales. This form of rock 

 lasts down to the junction with the nummulitic limestone. 



A good section is seen from the Nambor bridge on the Golaghar 



road, for about 2 miles up the river to the falls. 

 Nambor Falls. . r 



At the bridge a small patch of fine grey-shales 



is seen, and it is from this rock that the Nambor hot-spring rises. 

 Similar shales with hard calcareous bands are seen along the river 

 up to the falls, and one or two more small warm-springs are seen on 

 them. The dip is gentle and undulating. One or two of the cal- 

 careous bands have been quarried for limestone. 



A hundred yards below the Falls limestone is being extracted now 

 from beds which have always been regarded as cretaceous. In the 

 quarry 8 feet of fine, grey clay-shales overlie, with perfect conformity, 

 a* hard band of clay-limestone, full of oyster shells, and dipping 

 io c S.E. This band is 2 feet 6 inches thick, and passes down into a 

 soft bed of clay-shale, full of oyster shells above, but unfossiliferous 

 below, where it rests on the trap band overlying the gneiss. Frequent 

 small nodules of yellow pyrites occur in the soft shaley beds. 



There does not seem to me to be any doubt that the Nambor 

 shales and limestone belong to the lower Siwalik shale-series, 

 which can be traced continuously up to them throughout the whole 

 length of the Dhansiri valley. 



( 87 > 



