WHITE.] 



THE FAULT IN SHARP MOUNTAIISr. 



837 



into crushed fraginentarv talus, and to disappear on approaching- the 

 fault line, be^'ond which we lind the ordinary' red shale. Similarly, the 

 South coal itself is cut off at a short distance beyond the point, less than 

 1,000 feet from the gap, where it was abandoned on account of its squeezed 

 condition. The red shale of the Mauch Chunk is exposed 300 feet east 

 of Yoder's drift (1,600 feet from the gap), which is in the next higher 

 exposed coal (Peacock), mapped in the Anthracite Atlas as L^'kens No. 

 4; and it is probable that had the mine gangway, which, in the miners' 

 vernacular, "ended in fault," been driven 250 feet farther, it would 

 have penetrated olive-green and red shales. 



From the foregoing details it will be seen that the somewhat oblique 

 fault crossing Sharp Mountain just west of the knob that abuts against 

 Rausch Gap entirely cuts oft* the Pottsville formation and a portion, 

 at least, of the Lower Coal Measures, so that Coal Measures, probably 

 including the greater portion of the section shown on PI. CLXXXV, 

 Fig. 3, are thrust past the truncated Pottsville formation, or the red 

 shales, against which the lower coals, carrying fossils clearly typical of 

 the Productive Coal Measures, are found to abut. 



The Pottsville, if any part of that formation is present in Lor])erry 

 Gap, must lie to the west of that fault and south of the lower coal 

 (South bed) drifted in the gap. The cause of the displacement of the 

 formations between Lorberry and Rausch gaps may perhaps be ascribed 

 to the close group of folds to the north, and more immediately to the 

 pressure-thrust resulting from the Georges Head anticline. 



As interesting, as well as corroborative of the evidence of the plants of 

 the lower coals, I may add that the fossils from near the coal mapped as 

 the Buck Mountain bed at the north end of the gap comprise a Coal 

 Measures flora containing Odontoi^teris of the type of Brardii and 

 sevtn-al small Pecopterids indicative of a very high stage in the Coal 

 Measures. 



That the strata on the east side of Lorberry Creek are continued on 

 the west is pro\'ed 1)y the extension of the lower levels in the Peacock 

 and Umbehauer beds beneath the creek and for some distance beyond, 

 one of the gangways in the higher coal having been driven nearly 1,500 

 feet west of the creek. The strike of the coal is nearl}^ parallel to that 

 of the crest of the mountain. The continuit}^ of the series on the west 

 side is also shown in a general wa}' by the fossil plants. Thus the flora 

 from the rock dump at the south end on the west side of the gap may 

 also 1)0 cited in evidence: 



Mariopterirt cf. conlato-ovata (Weiss). 

 Pec(>j)tt'ris unita liroiijin. 

 Pecopteris eiiiargiiiata Goep}). 

 Pecopteris polyniorpha Broiifin. 

 Alcthopteris pennsylvanica Lx.? 

 N('nr()j)teris ovata Hoffin. 

 Neurupteris verinicularis Lx. 



Neuropteris fiml)riata Lx. 

 Neuropteris ('larksoni Lx. 

 Neuroptoris Schevichzeri Hoffin. 

 Anmilaria Htcllata (Schloth.) Wood. 

 Spheiiophylluni emarjj;inatuiu Brongn. 

 Lepidodendron sp. iiidt't. 

 Lei>idopliylluni oblongifoliuni Lx. 



