64 



some of the smaller streams which flow into the river from the 

 north, like Flint River, Limestone Creek, Elk River, Bluewater 

 Creek, and Shoal Creek, have eroded their valleys into the Tren- 

 ton limestone. These areas are crossed at only a few points by 

 the railroads leading out from Huntsville and Florence, and no 

 commercial use has yet been made of the rock. 



In the narrow anticlinal valleys below enumerated erosion 

 has in most cases sunk the floors of the valleys into Cambrian 

 strata, and, as a consequence, the Trenton limestone occupies a 

 narrow belt on each side, near the base of the Red Mountain 

 ridges. But since a fault usually occurs on one side of these 

 valleys, the Red Mountain ridges and the accompanying Tren- 

 ton limestone are mere fully represented on the unfaulted side, 

 which is the eastern side in all except Murphrees Valloy. While 

 the Trenton forms practically a continuous belt along the un- 

 disturbed side, extensive areas are sometimes found on the 

 faulted side also. This is the case, for instance, at Vance, on 

 the Alabama Great Southern Railroad, where the rock is quar- 

 ried for flux for the furnace of the Central Iron Company at 

 Tuscaloosa. Analysis I of Table B, shows its composition 

 here. Other series of analyses from lower ledges in the quarry 

 show only 1.22 per cent of silica, but more magnesia. 



In cases where erosion has not gone so deep as to reach the 

 Cambrian the Trenton may be found extending entirely across 

 the valleys. This is the case in the lower part of Browns Valley 

 from Brooksville to beyond Guntersville. Above Guntersville 

 the Trenton is seen mainly on the eastern side of the valley. 

 The river touches these outcrops at many points, and at Gun- 

 tersville the railroad connecting that city with Attalla would 

 afford an additional means of transportation. No develop- 

 ments have yet been made in this area. 



The valley separating the Warrior irom the Cahaba coal 

 field is known as Roups Valley in the southern and as Jones 

 Valley in the, northern part. In these the Trenton occupies a 

 narrow, continuous belt, usually near the base of the eastern 

 Red Mountain ridge, though in places it is high up on the ridge 

 and .even at its summit, as at Gate City, where the quarries of 

 the Sloss Iron Company are located. Many analyses of 

 the rock from these quarries have been made, and several are 

 given in Table B, (Nos, 2, 3, 4, 5, 6). 



