wALcorr.) SUMMARY — NORTHERN APPALACHIAN. 279 



Feet. 



(7) East of the Parker quarry the rocks are argillaceous shales, with occasional 



layerp of hard gray limestone one-half of an inch to 2 inches thick, that 



carry numerous fragments of a lmguloid shell 3,500 



Strike of shales near top of 7, N.40° to 60° E., dip 60° SE. 



(8) Light gray quart zite 50 



(9) Gray limestone in massive layers, with occasional intercalated bands of 



hard argillaceous shale similar to that beneath the limestone. Many of 

 the beds of limestone appear to have been broken up into fragments and 

 recemented in si hi 1,700 



Average strike of limestone bed3 N. 50° E., dip 50° to 90° ; average dip 

 G0° SB. 



In this limestone belt, 1 mile north of where the section crossed, a few 

 fossils were found; Lingula, n. sp., OrthUina undt. (fragment), Camerella 

 undt. (probably new), Agnoatus like A. orion, and Ptychoparia like P. 

 a dam si. 



(10) Argillaceous shales, very similar to those in the Parker lodge, continue on 



up to the opposite side of the line of the Vermont Central Railroad track. 

 At the base the shales rest couformably against the limestone of 9, and 

 above appear to be cut off by a fault. 



Strike N. 50° E.,dip '50° to H0° SE., for a distance beyond the limestone; 

 the dip then decreases and does not exceed 20° for a long distance, until 

 within 1,000 feet of the railroad track, where the shales become coarser 

 and changed by addition of arenaceous material, and thedip increases. 



Total thickness to fault line of No. 10,3,500 to 4,500 feet. 



No. 8 of the section when traced on its strike to the southwest increases in force 

 very rapidly to the thickness of 500 feet or more, aud also changes from a quartz ite to 

 a more or less calcareous sandstone, containing irregular fragments of argillaceous 

 shale. Followed to the northeast, it soon disappears aud the limestones rest directly 

 on the shales. Continuing northeast on the limestone (9), it is found to decrease rap- 

 idly, and a mile northeast of where it is over 1,500 feet in thickness the width across 

 the outcrop is not over 150 feet, aud soon the shales above it and those below it come 

 together, the limestone having disappeared. Southwest of the line of the section the 

 width of the outcrop narrows, and north of Georgia Plains post-office the entire 

 section is covered by beds of sand. 



No. 9 appears to be a great lenticular mass of limestone (lentile of Marcou) with 

 intercalated beds of argillaceous shale, and more rarely with arenaceous beds imbedded 

 in the argillaceous shales. The fauna is Cambrian in character, and, in the abseuce 

 of Olenellus and other typical Middle [now Lower] Cambrian fossils approaches that 

 of the Upper Cambrian or Potsdam sandstone. 



A section taken east of Highgate Springs beginning on the east 

 side of tbe same fault as the Georgia section, gives a slightly greater 

 thickness, and more arenaceous matter in the limestone series beneath 

 the Georgia shales. The limestones are here 1,170 feet in thickness and 

 the Georgia shales 1,000 feet, above which there is apparently a con- 

 formable series of calcareous sandstones, with a thickness of 850 feet, to 

 where they are cut off by a fault line. A section measured east of the 

 village of Swanton, does not show as great a thickness of the limestone 

 beneath the Georgia shale, and a fault line cuts obliquely across the 

 shale. On the east side of the fault 200 or 300 feet of shales occur, and 

 many layers of conglomerate limestone, the fragments of limestone 

 varying in size from small pebbles to masses 6 feet in diameter. The 



