PANOLA COUNTY. 241 



12. G-ray sandy clay and bluish sandy clay. (This is the source of 



the potter"s clay.) 6 to 8 feet. 



13. Siliceous laminated limestone. (Frequently micaceous and sandy 



between the laminae, with carbonized plant remains. Usually 



found near the water line of streams.) 2 to 2£ feet. 



14. Sandy clay 6 to 10 feet. 



15. Compact siliceous limestone. . 2 to 3 feet. 



16. Lignitic clay shale. (Usually of brownish color and sometimes 



containing plant fossils.) 6 inches to 2 feet. 



17. Compact lignitic clay. (Sometimes replaced locally by asphaltic 



clay with bluish sandy clay parting.) 1 to 2 feet. 



1 8. Lignite bed, varying in thickness and somewhat in quality, with 



partings of lignitized clay ' ... 2 to 44, feet. 



19. Shaly clay with hardpan partings 20 to 40 feet. 



20. Burned and metamorphic clay, as seen at Twoomy Creek and 



Beckville 1 to 2 feet. 



TWOOMY CREEK METAMORPHIC DISTURBANCE. 



• 



At a point about two and one-fourth miles above Beckville, where the 

 Texas, Sabine Valley and Northwestern Railway cuts through an embank- 

 ment just south of the trestle over Twoomy Creek, a tributary of Martin's 

 Creek, there is a peculiar formation in the west side of the railway cut. The 

 linear exposure north and south is about three hundred feet, having the fol- 

 lowing section : 



d. Surface red clay soil (subsequent deposit) 2 to 4 feet. 



b. Clay stratum, changing from nearly white on the south to yellow, red, 



bluish quartzite, and scoria toward the north, at squeeze 1 to 8 feet. 



a. Red earthy clay to bed of railway, except at the break and squeeze 4 to 6 feet. 



c. Squeeze. 



e. Twoomy Creek. 



Fig. 17. 



TWOOMY CREEK DISTURBANCE. 



The apparent dip of the clay stratum underlying the surface soil is about 

 thirty degrees southeast. The clay stratum exhibits evidence of various de- 

 grees of heat, which accounts for the various colors and the metamorphism 

 into quartzite. Near the north end of the railway cut this heat has been suf- 

 ficient to fuse the quartzite into scoria or cinder. The baked clay, quartzite, 

 and scoria have been used successfully as ballast for the road. An analysis 

 of the cinder by Mr. L. E. Magnenat shows its composition to be silica, 34.45; 

 sesquioxide of iron, 37.83; alumina, 14.17; lime, 10.00; magnesia, 0.43; alka- 



