83(l FLORAL ZONES OF THE POTTSVILLE FORMATION. 



sheet of tlie Topographir Atlas of the United States, is somewhat 

 abruptly sheared in a direetion apparently X. 15' E. Westward, 

 instead of a dense talus of massiv(> eonulomerate bowlders, whieh never 

 fails to mark the vieinity of the stiM'ply outeropping Pottsville con- 

 glomerates, we tind a gently rounded, smooth, broad ridge nearly 

 devoid of all talus of a coarse type. Furthermore, over this smooth 

 plateau surface there are scattered a nmnber of prospect shafts, in one 

 of whieh. less than 100 yards from the crushed ends of the conglom- 

 erates, and nearly in the prol)able strike of the horizon of Lykens 

 coal No, 1, I collected fragments of Annularia sphejiophylloides^ 

 t<ph> ii(q>liiilhnii <iii(ir<jinaium^ Neuropterh ovata^ N. plicata [Lx.], and 

 fragments apparently referable to N Scheuchzeri^ all species clearly 

 indicative of the Productive Coal Measures. On passing southeastward 

 from this point, across the line of displacement, the Mauch Chunk red 

 shale is found in its normal place below the remnant of the lower con- 

 glomerates of the Pottsville formation. The line of the fault appears 

 to be marked by a slight diagonal depression, by a zone of ferruginous 

 brown earth, by numerous springs, and l)y occasional more or less 

 obliquely or irregularly disposed trains of crv^shed sandstone or con- 

 glomerates. Beyond these, to the west, the shale and coal swales, or 

 the trains of thin sandstone talus marking the outcrop of the Coal 

 Measures shales, or of the relatively thin and less coarse Coal Measures 

 conglomerates, may be traced to their more complete exposures and 

 oriiMitation in the upper portion of the Lorberry Gap. 



The section shown in PI. CLXXXV was not instrumentally meas- 

 ured by me. though a tapeline was used; but it shows the approximate 

 relations of the t)eds exposed on the east side of the Lorberry Gap. 

 The nomenclature of the coals is that found in the early Report on the 

 Swatara Mining District. ^ The coals designated the South coal, the 

 Peacock coal, and the I'mbehauer coal are those respectively mapped 

 on mine sheet xxi as Lykens coal No, 6, Lykens coal No. 4, and the 

 Buck Mountain t-oal." 



The mantle of talus from the lowei- (wposures of conglomerate effect- 

 uall\- conceals the outcrop of the upper red shales of the Mauch Chunk 

 formation in the immediate vicinity of the gap. though it may be found 

 at some distance to the east as well as to the west of Lorberry Creek. 

 On the mine sheet the boundary of this red shale, which appears to be 

 somewhat hypothetically drawn, is given a gradual swing to the south, 

 on the supposition that there is a gentle tlexure of the formations. 

 The nearly vertical ledges displayed at the lower end of the gap 

 and situated below the coal (the South bed) mapped in the Atla^ as 

 Lykens No. (> arc successively found, when traced from the gap a 

 very short distance eastward, to be somewhat abruptly transformed 



' State U'K^sliitnre of Pennsylviiiiiix, 1S39. 



2 For more t-xact data as to the ititervals of the coals, the reader is referred to the published sections. 



