295 



into two formations, the lower and thicker of which is 

 called the James River, and the upper, the Baxter's Brook. 

 The strata lie in broad open folds on which have been 

 superposed smaller secondary folds. 



James River Formation. — The James River formation 

 is described by Fletcher and Williams as consisting of 

 clastic deposits of graywacke, silicified grits and banded 

 slates into which have been intruded rocks of such 

 varied character as granite, monzonite, rhyolite, quartz 

 porphyry, diabase and basalt. The thickness according 

 to Williams approximates one mile. Areally the rocks 

 of this formation constitute the greater portion of 

 the plateau and they contain most of "the beds" of 

 iron ore which have been prospected here for many 

 years. Some of the ore "beds" of the upper parts 

 are similar to those of the Belle Isle oolitic deposits of 

 Conception bay, Newfoundland, while other "beds" in 

 the formation consist of grit impregnated with hematite. 

 Williams inclines to the belief that the ores are of sedi- 

 mentary origin. Their economic importance and extent 

 are yet to be determined. From the iron ore and associ- 

 ated beds have been collected two species of inarticulate 

 brachiopods, determined by Schuchert as Obolus {Lin- 

 gulobolus) spissa and Lingulellaf 



Baxter's Brook Formation. — The James River rocks are 

 succeeded on the northern portion of the plateau by the 

 Baxter's Brook formation, consisting of metamorphosed 

 red and grey sandstones and slates. Like the rocks of the 

 preceding formation these have been cut by similar or the 

 same intrusives with the exception of monzonite. The 

 only fossils so far found are indeterminable Linguloids. 

 Williams estimates the present thickness at 500 feet which 

 is probably far less than the original. 



Ordovicianf 



Malignant Cove Formation. — -At Malignant Cove are 

 exposed about 20 feet of coarse cross-bedded conglomer- 

 ates and sands of varied color which rest unconformably 

 on cleavage surfaces of the James River slates. These 

 elastics contain material derived from all the preceding 

 sedimentaries and intrusives except the diabase and basal t. 



