Stevenson.] Id4: [Nov. 21, 



important coal beds described in the writer's sections* made on the head- 

 waters of Powell river in Wise county are persistent and have been recog- 

 nized as far east as Dump creelc. The associated roclis show the same 

 characteristics as on the headwaters of Powell river. Limestone appears 

 to be absent and one of the sandstones is coarsely conglomerate. 



The Lower Coal measures form the mass of Powell -Stone mountain 

 under the Stone Mountain anticlinal in Scott county, but they quickly pass 

 under the Middle Coal measures, owing to the rapid disappearance of that 

 axis eastward. No exposure appears on the northerly side of the Clinch 

 fault beyond Russell creek eastward. But the beds reappear on the south- 

 erly or upthrow side of that fault beyond Weaver creek in Russell county ; 

 as well as on the downthrow side of the Stony Ridge and Abb's Valley 

 faults in Tazewell county. The important mines at Pocahontas on Laurel 

 fork of Bluestone river in eastern Tazewell are in a bed belonging to this 

 group. Scott's mines on Middle creek, Christian's mines on Laurel fork 

 of Indian and Sayers' old mine on Dry fork of Sandy, all in Stony ridge, 

 are in beds belonging to the Lower Coal measures. No rocks belonging 

 to the higher group occur in Tazewell county or in Russell county east 

 from Lewis creek. The full thickness ot this group is not exposed within 

 the area examined and the higher beds must be sought for in Buchanan 

 county of Virginia and McDowell county of West Virginia. The passage 

 to the Lower Carboniferous is gradual. 



Ihe Loicer Carboniferous. 



Lower Carboniferous rocks occur in irregular strips along the fault lines. 

 The most important is that on the northerly or downthrow side of the 

 Saltville fault, which tapers in widtli from nearly five miles on the Ten- 

 nessee line to almost nothing at the easterly boundary of Smyth county. 

 The whole section is shown best in this strip. A narrow strip extends for a 

 little way on both sides of Dump creek along the New Garden fault and 

 another, also on the downthrow side of the same fault, begins near Lewis 

 creek and continues eastward certainly beyond Cavitt's creek. A third 

 strip is shown on the upthrow side of the Abb's Valley fault in Crockett's 

 cove and Abb's valley, while a fourth develops on the downthrow side of 

 the same fault along the waters of Bluestone river. 



The section of the Lower Carboniferous as shown in Washington county 

 was given in the previous memoir. There Prof. SafFord's classification 

 was accepted as follows : 



fl. Red shales, sandstones and 



i' 



Mountain limestone. 



thin limestones ; 

 Limestones and calca- 

 reous shales. 



Silicious group. 



t 



Cherty limestone ; 

 Protean group. 



♦Stevenson. Notes on the Geology of Wise, Lee and Scott counties, Virginia. 

 Read before Amer. Phil. Soc, Aug. 20, 1880. 



